Start work on IMAP probe

internal/cmd/jafar/README.md

@@ -156,16 +156,14 @@ response for every request whose `Host` contains the specified string.
 
 ### tls-proxy
 
-TLS proxy is a TCP proxy that routes traffic to specific servers depending
+TLS proxy is a proxy that routes traffic to specific servers depending
 on their SNI value. It is controlled by the following flags:
 
 ```bash
   -tls-proxy-address string
-        Address where the TCP+TLS proxy should listen (default "127.0.0.1:443")
+        Address where the HTTP proxy should listen (default "127.0.0.1:443")
   -tls-proxy-block value
-        Register SNI header keyword triggering TLS censorship
+        Register keyword triggering TLS censorship
-  -tls-proxy-outbound-port
-        Define the outbound port requests are proxied to (default "443 for HTTPS)
 ```
 
 The `-tls-proxy-address` flags has the same semantics it has for the DNS

internal/cmd/jafar/main.go

@@ -58,9 +58,8 @@ var (
 
 	tag *string
 
-	tlsProxyAddress      *string
+	tlsProxyAddress *string
-	tlsProxyBlock        flagx.StringArray
+	tlsProxyBlock   flagx.StringArray
-	tlsProxyOutboundPort *string
 
 	uncensoredResolverDoH *string
 )
@@ -160,16 +159,12 @@ func init() {
 	// tlsProxy
 	tlsProxyAddress = flag.String(
 		"tls-proxy-address", "127.0.0.1:443",
-		"Address where the TCP+TLS proxy should listen",
+		"Address where the HTTP proxy should listen",
 	)
 	flag.Var(
 		&tlsProxyBlock, "tls-proxy-block",
 		"Register keyword triggering TLS censorship",
 	)
-	tlsProxyOutboundPort = flag.String(
-		"tls-proxy-outbound-port", "443",
-		"The outbound port where requests should be proxied",
-	)
 
 	// uncensored
 	uncensoredResolverDoH = flag.String(
@@ -232,7 +227,7 @@ func iptablesStart() *iptables.CensoringPolicy {
 }
 
 func tlsProxyStart(uncensored *uncensored.Client) net.Listener {
-	proxy := tlsproxy.NewCensoringProxy(tlsProxyBlock, uncensored, tlsProxyOutboundPort)
+	proxy := tlsproxy.NewCensoringProxy(tlsProxyBlock, uncensored)
 	listener, err := proxy.Start(*tlsProxyAddress)
 	runtimex.PanicOnError(err, "proxy.Start failed")
 	return listener

internal/cmd/jafar/tlsproxy/tlsproxy.go

@@ -21,9 +21,8 @@ type Dialer interface {
 
 // CensoringProxy is a censoring TLS proxy
 type CensoringProxy struct {
-	keywords     []string
+	keywords []string
-	dial         func(network, address string) (net.Conn, error)
+	dial     func(network, address string) (net.Conn, error)
-	outboundPort string
 }
 
 // NewCensoringProxy creates a new CensoringProxy instance using
@@ -32,18 +31,13 @@ type CensoringProxy struct {
 // the SNII record of a ClientHello. dnsNetwork and dnsAddress are
 // settings to configure the upstream, non censored DNS.
 func NewCensoringProxy(
-	keywords []string, uncensored Dialer, outboundPort *string,
+	keywords []string, uncensored Dialer,
 ) *CensoringProxy {
-	defaultPort := "443"
-	if outboundPort == nil {
-		outboundPort = &defaultPort
-	}
 	return &CensoringProxy{
 		keywords: keywords,
 		dial: func(network, address string) (net.Conn, error) {
 			return uncensored.DialContext(context.Background(), network, address)
 		},
-		outboundPort: *outboundPort,
 	}
 }
 
@@ -152,7 +146,7 @@ func (p *CensoringProxy) handle(clientconn net.Conn) {
 			return
 		}
 	}
-	serverconn, err := p.dial("tcp", net.JoinHostPort(sni, p.outboundPort))
+	serverconn, err := p.dial("tcp", net.JoinHostPort(sni, "443"))
 	if err != nil {
 		log.WithError(err).Warn("tlsproxy: p.dial failed")
 		alertclose(clientconn)

internal/cmd/jafar/tlsproxy/tlsproxy_test.go

@@ -94,7 +94,7 @@ func TestFailWriteAfterConnect(t *testing.T) {
 
 func TestListenError(t *testing.T) {
 	proxy := NewCensoringProxy(
-		[]string{""}, uncensored.NewClient("https://1.1.1.1/dns-query"), nil,
+		[]string{""}, uncensored.NewClient("https://1.1.1.1/dns-query"),
 	)
 	listener, err := proxy.Start("8.8.8.8:80")
 	if err == nil {
@@ -107,7 +107,7 @@ func TestListenError(t *testing.T) {
 
 func newproxy(t *testing.T, blocked string) net.Listener {
 	proxy := NewCensoringProxy(
-		[]string{blocked}, uncensored.NewClient("https://1.1.1.1/dns-query"), nil,
+		[]string{blocked}, uncensored.NewClient("https://1.1.1.1/dns-query"),
 	)
 	listener, err := proxy.Start("127.0.0.1:0")
 	if err != nil {

internal/engine/experiment.go

@@ -92,12 +92,7 @@ func (eaw *experimentAsyncWrapper) RunAsync(
 	out := make(chan *model.ExperimentAsyncTestKeys)
 	measurement := eaw.experiment.newMeasurement(input)
 	start := time.Now()
-	args := &model.ExperimentArgs{
+	err := eaw.experiment.measurer.Run(ctx, eaw.session, measurement, eaw.callbacks)
-		Callbacks:   eaw.callbacks,
-		Measurement: measurement,
-		Session:     eaw.session,
-	}
-	err := eaw.experiment.measurer.Run(ctx, args)
 	stop := time.Now()
 	if err != nil {
 		return nil, err

internal/engine/experiment/dash/dash.go

@@ -249,10 +249,10 @@ func (m Measurer) ExperimentVersion() string {
 }
 
 // Run implements model.ExperimentMeasurer.Run.
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	tk := new(TestKeys)
 	measurement.TestKeys = tk
 	saver := &tracex.Saver{}

internal/engine/experiment/dash/dash_test.go

@@ -270,15 +270,15 @@ func TestMeasureWithCancelledContext(t *testing.T) {
 	cancel() // cause failure
 	measurement := new(model.Measurement)
 	m := &Measurer{}
-	args := &model.ExperimentArgs{
+	err := m.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableHTTPClient: http.DefaultClient,
 			MockableLogger:     log.Log,
 		},
-	}
+		measurement,
-	err := m.Run(ctx, args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	// See corresponding comment in Measurer.Run implementation to
 	// understand why here it's correct to return nil.
 	if !errors.Is(err, nil) {

internal/engine/experiment/dnscheck/dnscheck.go

@@ -120,11 +120,10 @@ var (
 )
 
 // Run implements model.ExperimentSession.Run
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
-
 	// 1. fill the measurement with test keys
 	tk := new(TestKeys)
 	tk.Lookups = make(map[string]urlgetter.TestKeys)

internal/engine/experiment/dnscheck/dnscheck_test.go

@@ -56,12 +56,12 @@ func TestExperimentNameAndVersion(t *testing.T) {
 
 func TestDNSCheckFailsWithoutInput(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{Domain: "example.com"})
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: new(model.Measurement),
+		newsession(),
-		Session:     newsession(),
+		new(model.Measurement),
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if !errors.Is(err, ErrInputRequired) {
 		t.Fatal("expected no input error")
 	}
@@ -69,12 +69,12 @@ func TestDNSCheckFailsWithoutInput(t *testing.T) {
 
 func TestDNSCheckFailsWithInvalidURL(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: &model.Measurement{Input: "Not a valid URL \x7f"},
+		newsession(),
-		Session:     newsession(),
+		&model.Measurement{Input: "Not a valid URL \x7f"},
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if !errors.Is(err, ErrInvalidURL) {
 		t.Fatal("expected invalid input error")
 	}
@@ -82,12 +82,12 @@ func TestDNSCheckFailsWithInvalidURL(t *testing.T) {
 
 func TestDNSCheckFailsWithUnsupportedProtocol(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: &model.Measurement{Input: "file://1.1.1.1"},
+		newsession(),
-		Session:     newsession(),
+		&model.Measurement{Input: "file://1.1.1.1"},
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if !errors.Is(err, ErrUnsupportedURLScheme) {
 		t.Fatal("expected unsupported scheme error")
 	}
@@ -100,12 +100,12 @@ func TestWithCancelledContext(t *testing.T) {
 		DefaultAddrs: "1.1.1.1 1.0.0.1",
 	})
 	measurement := &model.Measurement{Input: "dot://one.one.one.one"}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: measurement,
+		newsession(),
-		Session:     newsession(),
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(ctx, args)
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -147,12 +147,12 @@ func TestDNSCheckValid(t *testing.T) {
 		DefaultAddrs: "1.1.1.1 1.0.0.1",
 	})
 	measurement := model.Measurement{Input: "dot://one.one.one.one:853"}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: &measurement,
+		newsession(),
-		Session:     newsession(),
+		&measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if err != nil {
 		t.Fatalf("unexpected error: %s", err.Error())
 	}
@@ -195,12 +195,12 @@ func TestDNSCheckWait(t *testing.T) {
 	measurer := &Measurer{Endpoints: endpoints}
 	run := func(input string) {
 		measurement := model.Measurement{Input: model.MeasurementTarget(input)}
-		args := &model.ExperimentArgs{
+		err := measurer.Run(
-			Callbacks:   model.NewPrinterCallbacks(log.Log),
+			context.Background(),
-			Measurement: &measurement,
+			newsession(),
-			Session:     newsession(),
+			&measurement,
-		}
+			model.NewPrinterCallbacks(log.Log),
-		err := measurer.Run(context.Background(), args)
+		)
 		if err != nil {
 			t.Fatalf("unexpected error: %s", err.Error())
 		}

internal/engine/experiment/dnsping/dnsping.go

@@ -85,10 +85,12 @@ var (
 )
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
+	callbacks model.ExperimentCallbacks,
+) error {
 	if measurement.Input == "" {
 		return errNoInputProvided
 	}

internal/engine/experiment/dnsping/dnsping_test.go

@@ -61,12 +61,7 @@ func TestMeasurer_run(t *testing.T) {
 			MockableLogger: model.DiscardLogger,
 		}
 		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
-		args := &model.ExperimentArgs{
+		err := m.Run(ctx, sess, meas, callbacks)
-			Callbacks:   callbacks,
-			Measurement: meas,
-			Session:     sess,
-		}
-		err := m.Run(ctx, args)
 		return meas, m, err
 	}
 

internal/engine/experiment/example/example.go

@@ -57,10 +57,10 @@ func (m Measurer) ExperimentVersion() string {
 var ErrFailure = errors.New("mocked error")
 
 // Run implements model.ExperimentMeasurer.Run.
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	var err error
 	if m.config.ReturnError {
 		err = ErrFailure

internal/engine/experiment/example/example_test.go

@@ -26,12 +26,7 @@ func TestSuccess(t *testing.T) {
 	sess := &mockable.Session{MockableLogger: log.Log}
 	callbacks := model.NewPrinterCallbacks(sess.Logger())
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := m.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := m.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -52,12 +47,7 @@ func TestFailure(t *testing.T) {
 	ctx := context.Background()
 	sess := &mockable.Session{MockableLogger: log.Log}
 	callbacks := model.NewPrinterCallbacks(sess.Logger())
-	args := &model.ExperimentArgs{
+	err := m.Run(ctx, sess, new(model.Measurement), callbacks)
-		Callbacks:   callbacks,
-		Measurement: new(model.Measurement),
-		Session:     sess,
-	}
-	err := m.Run(ctx, args)
 	if !errors.Is(err, example.ErrFailure) {
 		t.Fatal("expected an error here")
 	}

internal/engine/experiment/fbmessenger/fbmessenger.go

@@ -157,10 +157,10 @@ func (m Measurer) ExperimentVersion() string {
 }
 
 // Run implements ExperimentMeasurer.Run
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
 	defer cancel()
 	urlgetter.RegisterExtensions(measurement)

internal/engine/experiment/fbmessenger/fbmessenger_test.go

@@ -35,12 +35,7 @@ func TestSuccess(t *testing.T) {
 	sess := newsession(t)
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -102,12 +97,7 @@ func TestWithCancelledContext(t *testing.T) {
 	sess := &mockable.Session{MockableLogger: log.Log}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/engine/experiment/hhfm/hhfm.go

@@ -90,10 +90,10 @@ var (
 )
 
 // Run implements ExperimentMeasurer.Run.
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	ctx, cancel := context.WithTimeout(ctx, 30*time.Second)
 	defer cancel()
 	urlgetter.RegisterExtensions(measurement)

internal/engine/experiment/hhfm/hhfm_test.go

@@ -45,12 +45,7 @@ func TestSuccess(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -158,12 +153,7 @@ func TestCancelledContext(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -269,12 +259,7 @@ func TestNoHelpers(t *testing.T) {
 	sess := &mockable.Session{}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, hhfm.ErrNoAvailableTestHelpers) {
 		t.Fatal("not the error we expected")
 	}
@@ -324,12 +309,7 @@ func TestNoActualHelpersInList(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, hhfm.ErrNoAvailableTestHelpers) {
 		t.Fatal("not the error we expected")
 	}
@@ -382,12 +362,7 @@ func TestWrongTestHelperType(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, hhfm.ErrInvalidHelperType) {
 		t.Fatal("not the error we expected")
 	}
@@ -440,12 +415,7 @@ func TestNewRequestFailure(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err == nil || !strings.HasSuffix(err.Error(), "invalid control character in URL") {
 		t.Fatal("not the error we expected")
 	}
@@ -502,12 +472,7 @@ func TestInvalidJSONBody(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/engine/experiment/hirl/hirl.go

@@ -78,10 +78,10 @@ var (
 )
 
 // Run implements ExperimentMeasurer.Run.
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	tk := new(TestKeys)
 	measurement.TestKeys = tk
 	if len(m.Methods) < 1 {

internal/engine/experiment/hirl/hirl_test.go

@@ -42,12 +42,7 @@ func TestSuccess(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -96,12 +91,7 @@ func TestCancelledContext(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -200,12 +190,7 @@ func TestWithFakeMethods(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -266,12 +251,7 @@ func TestWithNoMethods(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, hirl.ErrNoMeasurementMethod) {
 		t.Fatal("not the error we expected")
 	}
@@ -299,12 +279,7 @@ func TestNoHelpers(t *testing.T) {
 	sess := &mockable.Session{}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, hirl.ErrNoAvailableTestHelpers) {
 		t.Fatal("not the error we expected")
 	}
@@ -336,12 +311,7 @@ func TestNoActualHelperInList(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, hirl.ErrNoAvailableTestHelpers) {
 		t.Fatal("not the error we expected")
 	}
@@ -376,12 +346,7 @@ func TestWrongTestHelperType(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, hirl.ErrInvalidHelperType) {
 		t.Fatal("not the error we expected")
 	}

internal/engine/experiment/httphostheader/httphostheader.go

@@ -46,10 +46,12 @@ func (m *Measurer) ExperimentVersion() string {
 }
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
+	callbacks model.ExperimentCallbacks,
+) error {
 	if measurement.Input == "" {
 		return errors.New("experiment requires input")
 	}

internal/engine/experiment/httphostheader/httphostheader_test.go

@@ -30,12 +30,12 @@ func TestMeasurerMeasureNoMeasurementInput(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{
 		TestHelperURL: "http://www.google.com",
 	})
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: &model.Measurement{},
+		newsession(),
-		Session:     newsession(),
+		new(model.Measurement),
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if err == nil || err.Error() != "experiment requires input" {
 		t.Fatal("not the error we expected")
 	}
@@ -44,12 +44,12 @@ func TestMeasurerMeasureNoMeasurementInput(t *testing.T) {
 func TestMeasurerMeasureNoTestHelper(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
 	measurement := &model.Measurement{Input: "x.org"}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		newsession(),
-		Session:     newsession(),
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -75,12 +75,12 @@ func TestRunnerHTTPSetHostHeader(t *testing.T) {
 	measurement := &model.Measurement{
 		Input: "x.org",
 	}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		newsession(),
-		Session:     newsession(),
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if host != "x.org" {
 		t.Fatal("not the host we expected")
 	}

internal/engine/experiment/imap/imap.go

@@ -0,0 +1,416 @@
+package imap
+
+import (
+    "bufio"
+	"context"
+	"crypto/tls"
+	"fmt"
+	"github.com/pkg/errors"
+	"net"
+	//"net/smtp"
+	"net/url"
+    "strings"
+	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/engine/experiment/urlgetter"
+	"github.com/ooni/probe-cli/v3/internal/measurexlite"
+	"github.com/ooni/probe-cli/v3/internal/model"
+	"github.com/ooni/probe-cli/v3/internal/tracex"
+)
+
+var (
+	// errNoInputProvided indicates you didn't provide any input
+	errNoInputProvided = errors.New("not input provided")
+
+	// errInputIsNotAnURL indicates that input is not an URL
+	errInputIsNotAnURL = errors.New("input is not an URL")
+
+	// errInvalidScheme indicates that the scheme is invalid
+	errInvalidScheme = errors.New("scheme must be smtp(s)")
+)
+
+const (
+	testName    = "imap"
+	testVersion = "0.0.1"
+)
+
+// Config contains the experiment config.
+type Config struct{}
+
+type RuntimeConfig struct {
+	host       string
+	port       string
+	forced_tls bool
+	noop_count uint8
+}
+
+func config(input model.MeasurementTarget) (*RuntimeConfig, error) {
+	if input == "" {
+		// TODO: static input data (eg. gmail/riseup..)
+		return nil, errNoInputProvided
+	}
+
+	parsed, err := url.Parse(string(input))
+	if err != nil {
+		return nil, fmt.Errorf("%w: %s", errInputIsNotAnURL, err.Error())
+	}
+	if parsed.Scheme != "imap" && parsed.Scheme != "imaps" {
+		return nil, errInvalidScheme
+	}
+
+	port := ""
+
+	if parsed.Port() == "" {
+		// Default ports for StartTLS and forced TLS respectively
+		if parsed.Scheme == "imap" {
+			port = "143"
+		} else {
+			port = "993"
+		}
+	} else {
+		// Valid port is checked by URL parsing
+		port = parsed.Port()
+	}
+
+	valid_config := RuntimeConfig{
+		host:       parsed.Hostname(),
+		forced_tls: parsed.Scheme == "imaps",
+		port:       port,
+		noop_count: 10,
+	}
+
+	return &valid_config, nil
+}
+
+// TestKeys contains the experiment results
+
+type TestKeys struct {
+	Queries []*model.ArchivalDNSLookupResult `json:"queries"`
+	Runs    map[string]*IndividualTestKeys   `json:"runs"`
+	// Used for global failure (DNS resolution)
+	Failure string `json:"failure"`
+	// Indicates global failure or individual test failure
+	Failed bool `json:"failed"`
+}
+
+// IndividualTestKeys contains results for TCP/IP level stuff for each address found
+// in the DNS lookup
+type IndividualTestKeys struct {
+	NoOpCounter   uint8
+	TCPConnect    []*model.ArchivalTCPConnectResult         `json:"tcp_connect"`
+	TLSHandshakes []*model.ArchivalTLSOrQUICHandshakeResult `json:"tls_handshakes"`
+	// Individual failure aborting the test run for this address/port combo
+	Failure *string `json:"failure"`
+}
+
+type Measurer struct {
+	// Config contains the experiment settings. If empty we
+	// will be using default settings.
+	Config Config
+
+	// Getter is an optional getter to be used for testing.
+	Getter urlgetter.MultiGetter
+}
+
+// ExperimentName implements ExperimentMeasurer.ExperimentName
+func (m Measurer) ExperimentName() string {
+	return testName
+}
+
+// ExperimentVersion implements ExperimentMeasurer.ExperimentVersion
+func (m Measurer) ExperimentVersion() string {
+	return testVersion
+}
+
+// Manages sequential TCP sessions to the same hostname (over different IPs)
+// don't use in parallel!
+type TCPRunner struct {
+	trace     *measurexlite.Trace
+	logger    model.Logger
+	ctx       context.Context
+	tk        *TestKeys
+	tlsconfig *tls.Config
+	host      string
+	port      string
+	// addr is changed everytime TCPRunner.conn(addr) is called
+	addr string
+}
+
+type TCPSession struct {
+	addr     string
+	port     string
+	runner   *TCPRunner
+	tk       *IndividualTestKeys
+	tls      bool
+	raw_conn *net.Conn
+	tls_conn *net.Conn
+}
+
+func (s *TCPSession) Close() {
+	if s.tls {
+		var conn = *s.tls_conn
+		conn.Close()
+	} else {
+		var conn = *s.raw_conn
+		conn.Close()
+	}
+}
+
+func (s *TCPSession) current_conn() net.Conn {
+	if s.tls {
+		return *s.tls_conn
+	} else {
+		return *s.raw_conn
+	}
+}
+
+func (r *TCPRunner) run_key() string {
+	return net.JoinHostPort(r.addr, r.port)
+}
+
+func (r *TCPRunner) get_run() *IndividualTestKeys {
+	if r.tk.Runs == nil {
+		r.tk.Runs = make(map[string]*IndividualTestKeys)
+	}
+	key := r.run_key()
+	val, exists := r.tk.Runs[key]
+	if exists {
+		return val
+	} else {
+		r.tk.Runs[key] = &IndividualTestKeys{}
+		return r.tk.Runs[key]
+	}
+}
+
+func (r *TCPRunner) conn(addr string, port string) (*TCPSession, bool) {
+	r.addr = addr
+	run := r.get_run()
+
+	s := new(TCPSession)
+	if !s.conn(addr, port, r, run) {
+		return nil, false
+	}
+	return s, true
+}
+
+func (r *TCPRunner) dial(addr string, port string) (net.Conn, error) {
+	dialer := r.trace.NewDialerWithoutResolver(r.logger)
+	conn, err := dialer.DialContext(r.ctx, "tcp", net.JoinHostPort(addr, port))
+	run := r.get_run()
+	run.TCPConnect = append(run.TCPConnect, r.trace.TCPConnects()...)
+	return conn, err
+
+}
+
+func (s *TCPSession) conn(addr string, port string, runner *TCPRunner, tk *IndividualTestKeys) bool {
+	// Initialize addr field and corresponding errors in TestKeys
+	s.addr = addr
+	s.port = port
+	s.tls = false
+	s.runner = runner
+	s.tk = tk
+
+	conn, err := runner.dial(addr, port)
+	if err != nil {
+		s.error(err)
+		return false
+	}
+	s.raw_conn = &conn
+
+	return true
+}
+
+func (s *TCPSession) error(err error) {
+	s.runner.tk.Failed = true
+	s.tk.Failure = tracex.NewFailure(err)
+	//s. = append(s.errors, tracex.NewFailure(err))
+}
+
+func (r *TCPRunner) resolve(host string) ([]string, bool) {
+	r.logger.Infof("Resolving DNS for %s", host)
+	resolver := r.trace.NewStdlibResolver(r.logger)
+	addrs, err := resolver.LookupHost(r.ctx, host)
+	r.tk.Queries = append(r.tk.Queries, r.trace.DNSLookupsFromRoundTrip()...)
+	if err != nil {
+		r.tk.Failure = *tracex.NewFailure(err)
+		return []string{}, false
+	}
+	r.logger.Infof("Finished DNS for %s: %v", host, addrs)
+
+	return addrs, true
+}
+
+func (s *TCPSession) handshake() bool {
+	if s.tls {
+		// TLS already initialized...
+		return true
+	}
+	s.runner.logger.Infof("Starting TLS handshake with %s:%s", s.addr, s.port)
+	thx := s.runner.trace.NewTLSHandshakerStdlib(s.runner.logger)
+	tconn, _, err := thx.Handshake(s.runner.ctx, *s.raw_conn, s.runner.tlsconfig)
+	s.tk.TLSHandshakes = append(s.tk.TLSHandshakes, s.runner.trace.FirstTLSHandshakeOrNil())
+	if err != nil {
+		s.error(err)
+		return false
+	}
+
+	s.tls = true
+	s.tls_conn = &tconn
+	s.runner.logger.Infof("Handshake succeeded")
+	return true
+}
+
+func (s *TCPSession) starttls(message string) bool {
+	if s.tls {
+		// TLS already initialized...
+		return true
+	}
+	if message != "" {
+		s.runner.logger.Infof("Asking for StartTLS upgrade")
+		s.current_conn().Write([]byte(message))
+	}
+	return s.handshake()
+}
+
+func (s *TCPSession) imap(noop uint8) bool {
+    conn := s.current_conn()
+
+    command, err := bufio.NewReader(conn).ReadString('\n')
+    if err != nil {
+        s.error(err)
+        return false
+    }
+    if !strings.Contains(command, "CAPABILITY") {
+        s.error(errors.New("Unexpected IMAP reply: " + command))
+        return false
+    }
+
+
+    if noop > 0 {
+        s.runner.logger.Infof("Trying to generate no-op traffic")
+        s.tk.NoOpCounter = 0
+        for s.tk.NoOpCounter < noop {
+            s.tk.NoOpCounter += 1
+			s.runner.logger.Infof("NoOp Iteration %d", s.tk.NoOpCounter)
+
+            conn.Write([]byte("A1 NOOP\n"))
+            command, err := bufio.NewReader(conn).ReadString('\n')
+            if err != nil {
+                s.error(err)
+                break
+            }
+            if !strings.Contains(command, "OK NOOP") {
+                s.error(errors.New("Unexpected IMAP reply: " + command))
+                break
+            }
+        }
+
+        if s.tk.NoOpCounter == noop {
+			s.runner.logger.Infof("Successfully generated no-op traffic")
+			return true
+		} else {
+			s.runner.logger.Infof("Failed no-op traffic at iteration %d", s.tk.NoOpCounter)
+			return false
+		}
+    }
+
+    return true
+}
+
+// Run implements ExperimentMeasurer.Run
+func (m Measurer) Run(
+	ctx context.Context, sess model.ExperimentSession,
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
+) error {
+	log := sess.Logger()
+	trace := measurexlite.NewTrace(0, measurement.MeasurementStartTimeSaved)
+
+	config, err := config(measurement.Input)
+	if err != nil {
+		// Invalid input data, we don't even generate report
+		return err
+	}
+
+	tk := new(TestKeys)
+	measurement.TestKeys = tk
+
+	ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
+	defer cancel()
+
+	tlsconfig := tls.Config{
+		InsecureSkipVerify: false,
+		ServerName:         config.host,
+	}
+
+	runner := &TCPRunner{
+		trace:     trace,
+		logger:    log,
+		ctx:       ctx,
+		tk:        tk,
+		tlsconfig: &tlsconfig,
+		host:      config.host,
+		port:      config.port,
+	}
+
+	// First resolve DNS
+	addrs, success := runner.resolve(config.host)
+	if !success {
+		return nil
+	}
+
+	for _, addr := range addrs {
+		tcp_session, success := runner.conn(addr, config.port)
+		if !success {
+			continue
+		}
+		defer tcp_session.Close()
+
+		if config.forced_tls {
+			// Direct TLS connection
+			if !tcp_session.handshake() {
+				continue
+			}
+
+			// Try EHLO + NoOps
+			if !tcp_session.imap(config.noop_count) {
+				continue
+			}
+		} else {
+			// StartTLS...
+			if !tcp_session.starttls("A1 STARTTLS\n") {
+				continue
+			}
+
+			if !tcp_session.imap(config.noop_count) {
+				continue
+			}
+		}
+	}
+
+	return nil
+}
+
+// NewExperimentMeasurer creates a new ExperimentMeasurer.
+func NewExperimentMeasurer(config Config) model.ExperimentMeasurer {
+	return Measurer{Config: config}
+}
+
+// SummaryKeys contains summary keys for this experiment.
+//
+// Note that this structure is part of the ABI contract with ooniprobe
+// therefore we should be careful when changing it.
+type SummaryKeys struct {
+	//DNSBlocking bool `json:"facebook_dns_blocking"`
+	//TCPBlocking bool `json:"facebook_tcp_blocking"`
+	IsAnomaly bool `json:"-"`
+}
+
+// GetSummaryKeys implements model.ExperimentMeasurer.GetSummaryKeys.
+func (m Measurer) GetSummaryKeys(measurement *model.Measurement) (interface{}, error) {
+	sk := SummaryKeys{IsAnomaly: false}
+	_, ok := measurement.TestKeys.(*TestKeys)
+	if !ok {
+		return sk, errors.New("invalid test keys type")
+	}
+	return sk, nil
+}

internal/engine/experiment/imap/imap_test.go

@@ -0,0 +1,186 @@
+package imap
+
+import (
+	"bufio"
+	"context"
+	"crypto/tls"
+    //"encoding/json"
+	"errors"
+	"fmt"
+	"net"
+	"strings"
+	"testing"
+
+	"github.com/ooni/probe-cli/v3/internal/engine/mockable"
+	"github.com/ooni/probe-cli/v3/internal/model"
+)
+
+func plaintextListener() net.Listener {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		if l, err = net.Listen("tcp6", "[::1]:0"); err != nil {
+			panic(fmt.Sprintf("httptest: failed to listen on a port: %v", err))
+		}
+	}
+	return l
+}
+
+func tlsListener(l net.Listener) net.Listener {
+	return tls.NewListener(l, &tls.Config{})
+}
+
+func listener_addr(l net.Listener) string {
+	return l.Addr().String()
+}
+
+func ValidIMAPServer(conn net.Conn) {
+	for {
+		command, err := bufio.NewReader(conn).ReadString('\n')
+		if err != nil {
+			return
+		}
+
+		if strings.Contains(command, "NOOP") {
+			conn.Write([]byte("A1 OK NOOP completed.\n"))
+		} else if command == "STARTTLS" {
+			conn.Write([]byte("A1 OK Begin TLS negotiation now.\n"))
+			// TODO: conn.Close does not actually close connection? or does client not detect it?
+			conn.Close()
+			return
+		}
+        conn.Write([]byte("\n"))
+	}
+}
+
+func TCPServer(l net.Listener) {
+	for {
+		conn, err := l.Accept()
+		if err != nil {
+			continue
+		}
+		defer conn.Close()
+		conn.Write([]byte("* OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ STARTTLS LOGINDISABLED] howdy, ready.\n"))
+		ValidIMAPServer(conn)
+	}
+}
+
+func TestMeasurer_run(t *testing.T) {
+	// runHelper is an helper function to run this set of tests.
+	runHelper := func(input string) (*model.Measurement, model.ExperimentMeasurer, error) {
+		m := NewExperimentMeasurer(Config{})
+		if m.ExperimentName() != "imap" {
+			t.Fatal("invalid experiment name")
+		}
+		if m.ExperimentVersion() != "0.0.1" {
+			t.Fatal("invalid experiment version")
+		}
+		ctx := context.Background()
+		meas := &model.Measurement{
+			Input: model.MeasurementTarget(input),
+		}
+		sess := &mockable.Session{
+			MockableLogger: model.DiscardLogger,
+		}
+		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
+		err := m.Run(ctx, sess, meas, callbacks)
+		return meas, m, err
+	}
+
+	t.Run("with empty input", func(t *testing.T) {
+		_, _, err := runHelper("")
+		if !errors.Is(err, errNoInputProvided) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with invalid URL", func(t *testing.T) {
+		_, _, err := runHelper("\t")
+		if !errors.Is(err, errInputIsNotAnURL) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with invalid scheme", func(t *testing.T) {
+		_, _, err := runHelper("https://8.8.8.8:443/")
+		if !errors.Is(err, errInvalidScheme) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with broken TLS", func(t *testing.T) {
+		p := plaintextListener()
+		defer p.Close()
+
+		l := tlsListener(p)
+		defer l.Close()
+		addr := listener_addr(l)
+		go TCPServer(l)
+
+		meas, m, err := runHelper("imaps://" + addr)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		tk := meas.TestKeys.(*TestKeys)
+
+		for _, run := range tk.Runs {
+			for _, handshake := range run.TLSHandshakes {
+				if *handshake.Failure != "unknown_failure: remote error: tls: unrecognized name" {
+					t.Fatal("expected unrecognized_name in TLS handshake")
+				}
+			}
+
+			if run.NoOpCounter != 0 {
+				t.Fatalf("expected to not have any noops, not %d noops", run.NoOpCounter)
+			}
+		}
+
+		ask, err := m.GetSummaryKeys(meas)
+		if err != nil {
+			t.Fatal("cannot obtain summary")
+		}
+		summary := ask.(SummaryKeys)
+		if summary.IsAnomaly {
+			t.Fatal("expected no anomaly")
+		}
+	})
+
+	t.Run("with broken starttls", func(t *testing.T) {
+		l := plaintextListener()
+		defer l.Close()
+		addr := listener_addr(l)
+
+		go TCPServer(l)
+
+		meas, m, err := runHelper("imap://" + addr)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		tk := meas.TestKeys.(*TestKeys)
+        //bs, _ := json.Marshal(tk)
+        //fmt.Println(string(bs))
+
+		for _, run := range tk.Runs {
+			for _, handshake := range run.TLSHandshakes {
+				if *handshake.Failure != "unknown_failure: tls: first record does not look like a TLS handshake" {
+
+					t.Fatal("expected broken handshake")
+				}
+			}
+
+			if run.NoOpCounter != 0 {
+				t.Fatalf("expected to not have any noops, not %d noops", run.NoOpCounter)
+			}
+		}
+
+		ask, err := m.GetSummaryKeys(meas)
+		if err != nil {
+			t.Fatal("cannot obtain summary")
+		}
+		summary := ask.(SummaryKeys)
+		if summary.IsAnomaly {
+			t.Fatal("expected no anomaly")
+		}
+	})
+}

internal/engine/experiment/ndt7/ndt7.go

@@ -210,10 +210,10 @@ func (m *Measurer) doUpload(
 }
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	tk := new(TestKeys)
 	tk.Protocol = 7
 	measurement.TestKeys = tk

internal/engine/experiment/ndt7/ndt7_test.go

@@ -84,12 +84,7 @@ func TestRunWithCancelledContext(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	cancel() // immediately cancel
 	meas := &model.Measurement{}
-	args := &model.ExperimentArgs{
+	err := m.Run(ctx, sess, meas, model.NewPrinterCallbacks(log.Log))
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
-		Measurement: meas,
-		Session:     sess,
-	}
-	err := m.Run(ctx, args)
 	// Here we get nil because we still want to submit this measurement
 	if !errors.Is(err, nil) {
 		t.Fatal("not the error we expected")
@@ -109,15 +104,15 @@ func TestGood(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	measurer := NewExperimentMeasurer(Config{})
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableHTTPClient: http.DefaultClient,
 			MockableLogger:     log.Log,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -138,15 +133,15 @@ func TestFailDownload(t *testing.T) {
 		cancel()
 	}
 	meas := &model.Measurement{}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: meas,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableHTTPClient: http.DefaultClient,
 			MockableLogger:     log.Log,
 		},
-	}
+		meas,
-	err := measurer.Run(ctx, args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	// We expect a nil failure here because we want to submit anyway
 	// a measurement that failed to connect to m-lab.
 	if err != nil {
@@ -169,15 +164,15 @@ func TestFailUpload(t *testing.T) {
 		cancel()
 	}
 	meas := &model.Measurement{}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: meas,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableHTTPClient: http.DefaultClient,
 			MockableLogger:     log.Log,
 		},
-	}
+		meas,
-	err := measurer.Run(ctx, args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	// Here we expect a nil error because we want to submit this measurement
 	if err != nil {
 		t.Fatal(err)
@@ -202,15 +197,15 @@ func TestDownloadJSONUnmarshalFail(t *testing.T) {
 		seenError = true
 		return expected
 	}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: &model.Measurement{},
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableHTTPClient: http.DefaultClient,
 			MockableLogger:     log.Log,
 		},
-	}
+		new(model.Measurement),
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/engine/experiment/portfiltering/measurer.go

@@ -38,10 +38,12 @@ var (
 )
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
+	callbacks model.ExperimentCallbacks,
+) error {
 	// TODO(DecFox): Replace the localhost deployment with an OONI testhelper
 	// Ensure that we only do this once we have a deployed testhelper
 	testhelper := "http://127.0.0.1"

internal/engine/experiment/portfiltering/measurer_test.go

@@ -29,12 +29,7 @@ func TestMeasurer_run(t *testing.T) {
 	}
 	callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
 	ctx := context.Background()
-	args := &model.ExperimentArgs{
+	err := m.Run(ctx, sess, meas, callbacks)
-		Callbacks:   callbacks,
-		Measurement: meas,
-		Session:     sess,
-	}
-	err := m.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/engine/experiment/psiphon/psiphon.go

@@ -66,10 +66,10 @@ func (m *Measurer) printprogress(
 }
 
 // Run runs the measurement
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	const maxruntime = 300
 	ctx, cancel := context.WithTimeout(ctx, maxruntime*time.Second)
 	var (

internal/engine/experiment/psiphon/psiphon_test.go

@@ -33,12 +33,8 @@ func TestRunWithCancelledContext(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	cancel() // fail immediately
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, newfakesession(), measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     newfakesession(),
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, nil) { // nil because we want to submit the measurement
 		t.Fatal("expected another error here")
 	}
@@ -68,12 +64,8 @@ func TestRunWithCustomInputAndCancelledContext(t *testing.T) {
 	}
 	ctx, cancel := context.WithCancel(context.Background())
 	cancel() // fail immediately
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, newfakesession(), measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     newfakesession(),
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, nil) { // nil because we want to submit the measurement
 		t.Fatal("expected another error here")
 	}
@@ -92,12 +84,7 @@ func TestRunWillPrintSomethingWithCancelledContext(t *testing.T) {
 		cancel() // fail after we've given the printer a chance to run
 	}
 	observer := observerCallbacks{progress: &atomicx.Int64{}}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, newfakesession(), measurement, observer)
-		Callbacks:   observer,
-		Measurement: measurement,
-		Session:     newfakesession(),
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, nil) { // nil because we want to submit the measurement
 		t.Fatal("expected another error here")
 	}

internal/engine/experiment/quicping/quicping.go

@@ -221,11 +221,12 @@ func (m *Measurer) receiver(
 }
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
-
+	callbacks model.ExperimentCallbacks,
+) error {
 	host := string(measurement.Input)
 	// allow URL input
 	if u, err := url.ParseRequestURI(host); err == nil {

internal/engine/experiment/quicping/quicping_test.go

@@ -33,12 +33,8 @@ func TestInvalidHost(t *testing.T) {
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("a.a.a.a")
 	sess := &mockable.Session{MockableLogger: log.Log}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(context.Background(), sess, measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(context.Background(), args)
 	if err == nil {
 		t.Fatal("expected an error here")
 	}
@@ -57,12 +53,8 @@ func TestURLInput(t *testing.T) {
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("https://google.com/")
 	sess := &mockable.Session{MockableLogger: log.Log}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(context.Background(), sess, measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(context.Background(), args)
 	if err != nil {
 		t.Fatal("unexpected error")
 	}
@@ -81,12 +73,8 @@ func TestSuccess(t *testing.T) {
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("google.com")
 	sess := &mockable.Session{MockableLogger: log.Log}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(context.Background(), sess, measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(context.Background(), args)
 	if err != nil {
 		t.Fatal("did not expect an error here")
 	}
@@ -129,12 +117,8 @@ func TestWithCancelledContext(t *testing.T) {
 	sess := &mockable.Session{MockableLogger: log.Log}
 	ctx, cancel := context.WithCancel(context.Background())
 	cancel()
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal("did not expect an error here")
 	}
@@ -154,12 +138,8 @@ func TestListenFails(t *testing.T) {
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("google.com")
 	sess := &mockable.Session{MockableLogger: log.Log}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(context.Background(), sess, measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(context.Background(), args)
 	if err == nil {
 		t.Fatal("expected an error here")
 	}
@@ -202,12 +182,8 @@ func TestWriteFails(t *testing.T) {
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("google.com")
 	sess := &mockable.Session{MockableLogger: log.Log}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(context.Background(), sess, measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(context.Background(), args)
 	if err != nil {
 		t.Fatal("unexpected error")
 	}
@@ -263,12 +239,8 @@ func TestReadFails(t *testing.T) {
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("google.com")
 	sess := &mockable.Session{MockableLogger: log.Log}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(context.Background(), sess, measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(context.Background(), args)
 	if err != nil {
 		t.Fatal("unexpected error")
 	}
@@ -299,12 +271,8 @@ func TestNoResponse(t *testing.T) {
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("ooni.org")
 	sess := &mockable.Session{MockableLogger: log.Log}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(context.Background(), sess, measurement,
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		model.NewPrinterCallbacks(log.Log))
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(context.Background(), args)
 	if err != nil {
 		t.Fatal("did not expect an error here")
 	}

internal/engine/experiment/riseupvpn/riseupvpn.go

@@ -175,11 +175,8 @@ func (m Measurer) ExperimentVersion() string {
 }
 
 // Run implements ExperimentMeasurer.Run.
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(ctx context.Context, sess model.ExperimentSession,
-	callbacks := args.Callbacks
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks) error {
-	measurement := args.Measurement
-	sess := args.Session
-
 	ctx, cancel := context.WithTimeout(ctx, 90*time.Second)
 	defer cancel()
 	testkeys := NewTestKeys()

internal/engine/experiment/riseupvpn/riseupvpn_test.go

@@ -100,7 +100,7 @@ const (
 					"cert": "XXXXXXXXXXXXXXXXXXXXXXXXX",
 					"iatMode": "0"
 				  }
-				},
+				},              
 				{
 				  "type":"openvpn",
 				  "protocols":[
@@ -328,12 +328,7 @@ func TestInvalidCaCert(t *testing.T) {
 	sess := &mockable.Session{MockableLogger: log.Log}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -604,12 +599,7 @@ func TestMissingTransport(t *testing.T) {
 	sess := &mockable.Session{MockableLogger: log.Log}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err = measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err = measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -800,14 +790,14 @@ func runDefaultMockTest(t *testing.T, multiGetter urlgetter.MultiGetter) *model.
 	}
 
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: log.Log,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 
 	if err != nil {
 		t.Fatal(err)

internal/engine/experiment/run/dnscheck.go

@@ -21,10 +21,5 @@ func (m *dnsCheckMain) do(ctx context.Context, input StructuredInput,
 	measurement.TestName = exp.ExperimentName()
 	measurement.TestVersion = exp.ExperimentVersion()
 	measurement.Input = model.MeasurementTarget(input.Input)
-	args := &model.ExperimentArgs{
+	return exp.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	return exp.Run(ctx, args)
 }

internal/engine/experiment/run/run.go

@@ -46,10 +46,10 @@ type StructuredInput struct {
 }
 
 // Run implements ExperimentMeasurer.ExperimentVersion.
-func (Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	var input StructuredInput
 	if err := json.Unmarshal([]byte(measurement.Input), &input); err != nil {
 		return err

internal/engine/experiment/run/run_test.go

@@ -31,12 +31,7 @@ func TestRunDNSCheckWithCancelledContext(t *testing.T) {
 	cancel() // fail immediately
 	sess := &mockable.Session{MockableLogger: log.Log}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	// TODO(bassosimone): here we could improve the tests by checking
 	// whether the result makes sense for a cancelled context.
 	if err != nil {
@@ -67,12 +62,7 @@ func TestRunURLGetterWithCancelledContext(t *testing.T) {
 	cancel() // fail immediately
 	sess := &mockable.Session{MockableLogger: log.Log}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil { // here we expected nil b/c we want to submit the measurement
 		t.Fatal(err)
 	}
@@ -96,12 +86,7 @@ func TestRunWithInvalidJSON(t *testing.T) {
 	ctx := context.Background()
 	sess := &mockable.Session{MockableLogger: log.Log}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err == nil || err.Error() != "invalid character '}' looking for beginning of value" {
 		t.Fatalf("not the error we expected: %+v", err)
 	}
@@ -115,12 +100,7 @@ func TestRunWithUnknownExperiment(t *testing.T) {
 	ctx := context.Background()
 	sess := &mockable.Session{MockableLogger: log.Log}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err == nil || err.Error() != "no such experiment: antani" {
 		t.Fatalf("not the error we expected: %+v", err)
 	}

internal/engine/experiment/run/urlgetter.go

@@ -18,10 +18,5 @@ func (m *urlGetterMain) do(ctx context.Context, input StructuredInput,
 	measurement.TestName = exp.ExperimentName()
 	measurement.TestVersion = exp.ExperimentVersion()
 	measurement.Input = model.MeasurementTarget(input.Input)
-	args := &model.ExperimentArgs{
+	return exp.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	return exp.Run(ctx, args)
 }

internal/engine/experiment/signal/signal.go

@@ -141,10 +141,8 @@ func (m Measurer) ExperimentVersion() string {
 }
 
 // Run implements ExperimentMeasurer.Run
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(ctx context.Context, sess model.ExperimentSession,
-	callbacks := args.Callbacks
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks) error {
-	measurement := args.Measurement
-	sess := args.Session
 	ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
 	defer cancel()
 	urlgetter.RegisterExtensions(measurement)

internal/engine/experiment/signal/signal_test.go

@@ -25,14 +25,14 @@ func TestNewExperimentMeasurer(t *testing.T) {
 func TestGood(t *testing.T) {
 	measurer := signal.NewExperimentMeasurer(signal.Config{})
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: log.Log,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -103,14 +103,14 @@ func TestBadSignalCA(t *testing.T) {
 		SignalCA: "INVALIDCA",
 	})
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: log.Log,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if err.Error() != "AppendCertsFromPEM failed" {
 		t.Fatal("not the error we expected")
 	}

internal/engine/experiment/simplequicping/simplequicping.go

@@ -112,11 +112,12 @@ var (
 )
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
-
+	callbacks model.ExperimentCallbacks,
+) error {
 	if measurement.Input == "" {
 		return errNoInputProvided
 	}

internal/engine/experiment/simplequicping/simplequicping_test.go

@@ -65,12 +65,7 @@ func TestMeasurer_run(t *testing.T) {
 			MockableLogger: model.DiscardLogger,
 		}
 		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
-		args := &model.ExperimentArgs{
+		err := m.Run(ctx, sess, meas, callbacks)
-			Callbacks:   callbacks,
-			Measurement: meas,
-			Session:     sess,
-		}
-		err := m.Run(ctx, args)
 		return meas, m, err
 	}
 

internal/engine/experiment/smtp/smtp.go

@@ -0,0 +1,413 @@
+package smtp
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"github.com/pkg/errors"
+	"net"
+	"net/smtp"
+	"net/url"
+	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/engine/experiment/urlgetter"
+	"github.com/ooni/probe-cli/v3/internal/measurexlite"
+	"github.com/ooni/probe-cli/v3/internal/model"
+	"github.com/ooni/probe-cli/v3/internal/tracex"
+)
+
+var (
+	// errNoInputProvided indicates you didn't provide any input
+	errNoInputProvided = errors.New("not input provided")
+
+	// errInputIsNotAnURL indicates that input is not an URL
+	errInputIsNotAnURL = errors.New("input is not an URL")
+
+	// errInvalidScheme indicates that the scheme is invalid
+	errInvalidScheme = errors.New("scheme must be smtp(s)")
+)
+
+const (
+	testName    = "smtp"
+	testVersion = "0.0.1"
+)
+
+// Config contains the experiment config.
+type Config struct{}
+
+type RuntimeConfig struct {
+	host       string
+	port       string
+	forced_tls bool
+	noop_count uint8
+}
+
+func config(input model.MeasurementTarget) (*RuntimeConfig, error) {
+	if input == "" {
+		// TODO: static input data (eg. gmail/riseup..)
+		return nil, errNoInputProvided
+	}
+
+	parsed, err := url.Parse(string(input))
+	if err != nil {
+		return nil, fmt.Errorf("%w: %s", errInputIsNotAnURL, err.Error())
+	}
+	if parsed.Scheme != "smtp" && parsed.Scheme != "smtps" {
+		return nil, errInvalidScheme
+	}
+
+	port := ""
+
+	if parsed.Port() == "" {
+		// Default ports for StartTLS and forced TLS respectively
+		if parsed.Scheme == "smtp" {
+			port = "587"
+		} else {
+			port = "465"
+		}
+	} else {
+		// Valid port is checked by URL parsing
+		port = parsed.Port()
+	}
+
+	valid_config := RuntimeConfig{
+		host:       parsed.Hostname(),
+		forced_tls: parsed.Scheme == "smtps",
+		port:       port,
+		noop_count: 10,
+	}
+
+	return &valid_config, nil
+}
+
+// TestKeys contains the experiment results
+
+type TestKeys struct {
+	Queries []*model.ArchivalDNSLookupResult `json:"queries"`
+	Runs    map[string]*IndividualTestKeys   `json:"runs"`
+	// Used for global failure (DNS resolution)
+	Failure string `json:"failure"`
+	// Indicates global failure or individual test failure
+	Failed bool `json:"failed"`
+}
+
+// IndividualTestKeys contains results for TCP/IP level stuff for each address found
+// in the DNS lookup
+type IndividualTestKeys struct {
+	NoOpCounter   uint8
+	TCPConnect    []*model.ArchivalTCPConnectResult         `json:"tcp_connect"`
+	TLSHandshakes []*model.ArchivalTLSOrQUICHandshakeResult `json:"tls_handshakes"`
+	// Individual failure aborting the test run for this address/port combo
+	Failure *string `json:"failure"`
+}
+
+type Measurer struct {
+	// Config contains the experiment settings. If empty we
+	// will be using default settings.
+	Config Config
+
+	// Getter is an optional getter to be used for testing.
+	Getter urlgetter.MultiGetter
+}
+
+// ExperimentName implements ExperimentMeasurer.ExperimentName
+func (m Measurer) ExperimentName() string {
+	return testName
+}
+
+// ExperimentVersion implements ExperimentMeasurer.ExperimentVersion
+func (m Measurer) ExperimentVersion() string {
+	return testVersion
+}
+
+// Manages sequential TCP sessions to the same hostname (over different IPs)
+// don't use in parallel!
+type TCPRunner struct {
+	trace     *measurexlite.Trace
+	logger    model.Logger
+	ctx       context.Context
+	tk        *TestKeys
+	tlsconfig *tls.Config
+	host      string
+	port      string
+	// addr is changed everytime TCPRunner.conn(addr) is called
+	addr string
+}
+
+type TCPSession struct {
+	addr     string
+	port     string
+	runner   *TCPRunner
+	tk       *IndividualTestKeys
+	tls      bool
+	raw_conn *net.Conn
+	tls_conn *net.Conn
+}
+
+func (s *TCPSession) Close() {
+	if s.tls {
+		var conn = *s.tls_conn
+		conn.Close()
+	} else {
+		var conn = *s.raw_conn
+		conn.Close()
+	}
+}
+
+func (s *TCPSession) current_conn() net.Conn {
+	if s.tls {
+		return *s.tls_conn
+	} else {
+		return *s.raw_conn
+	}
+}
+
+func (r *TCPRunner) run_key() string {
+	return net.JoinHostPort(r.addr, r.port)
+}
+
+func (r *TCPRunner) get_run() *IndividualTestKeys {
+	if r.tk.Runs == nil {
+		r.tk.Runs = make(map[string]*IndividualTestKeys)
+	}
+	key := r.run_key()
+	val, exists := r.tk.Runs[key]
+	if exists {
+		return val
+	} else {
+		r.tk.Runs[key] = &IndividualTestKeys{}
+		return r.tk.Runs[key]
+	}
+}
+
+func (r *TCPRunner) conn(addr string, port string) (*TCPSession, bool) {
+	r.addr = addr
+	run := r.get_run()
+
+	s := new(TCPSession)
+	if !s.conn(addr, port, r, run) {
+		return nil, false
+	}
+	return s, true
+}
+
+func (r *TCPRunner) dial(addr string, port string) (net.Conn, error) {
+	dialer := r.trace.NewDialerWithoutResolver(r.logger)
+	conn, err := dialer.DialContext(r.ctx, "tcp", net.JoinHostPort(addr, port))
+	run := r.get_run()
+	run.TCPConnect = append(run.TCPConnect, r.trace.TCPConnects()...)
+	return conn, err
+
+}
+
+func (s *TCPSession) conn(addr string, port string, runner *TCPRunner, tk *IndividualTestKeys) bool {
+	// Initialize addr field and corresponding errors in TestKeys
+	s.addr = addr
+	s.port = port
+	s.tls = false
+	s.runner = runner
+	s.tk = tk
+
+	conn, err := runner.dial(addr, port)
+	if err != nil {
+		s.error(err)
+		return false
+	}
+	s.raw_conn = &conn
+
+	return true
+}
+
+func (s *TCPSession) error(err error) {
+	s.runner.tk.Failed = true
+	s.tk.Failure = tracex.NewFailure(err)
+	//s. = append(s.errors, tracex.NewFailure(err))
+}
+
+func (r *TCPRunner) resolve(host string) ([]string, bool) {
+	r.logger.Infof("Resolving DNS for %s", host)
+	resolver := r.trace.NewStdlibResolver(r.logger)
+	addrs, err := resolver.LookupHost(r.ctx, host)
+	r.tk.Queries = append(r.tk.Queries, r.trace.DNSLookupsFromRoundTrip()...)
+	if err != nil {
+		r.tk.Failure = *tracex.NewFailure(err)
+		return []string{}, false
+	}
+	r.logger.Infof("Finished DNS for %s: %v", host, addrs)
+
+	return addrs, true
+}
+
+func (s *TCPSession) handshake() bool {
+	if s.tls {
+		// TLS already initialized...
+		return true
+	}
+	s.runner.logger.Infof("Starting TLS handshake with %s:%s", s.addr, s.port)
+	thx := s.runner.trace.NewTLSHandshakerStdlib(s.runner.logger)
+	tconn, _, err := thx.Handshake(s.runner.ctx, *s.raw_conn, s.runner.tlsconfig)
+	s.tk.TLSHandshakes = append(s.tk.TLSHandshakes, s.runner.trace.FirstTLSHandshakeOrNil())
+	if err != nil {
+		s.error(err)
+		return false
+	}
+
+	s.tls = true
+	s.tls_conn = &tconn
+	s.runner.logger.Infof("Handshake succeeded")
+	return true
+}
+
+func (s *TCPSession) starttls(message string) bool {
+	if s.tls {
+		// TLS already initialized...
+		return true
+	}
+	if message != "" {
+		s.runner.logger.Infof("Asking for StartTLS upgrade")
+		s.current_conn().Write([]byte(message))
+	}
+	return s.handshake()
+}
+
+func (s *TCPSession) smtp(ehlo string, noop uint8) bool {
+	// Auto-choose plaintext/TCP session
+	client, err := smtp.NewClient(s.current_conn(), ehlo)
+	if err != nil {
+		s.error(err)
+		return false
+	}
+	err = client.Hello(ehlo)
+	if err != nil {
+		s.error(err)
+		return false
+	}
+
+	if noop > 0 {
+		s.runner.logger.Infof("Trying to generate more no-op traffic")
+		// TODO: noop counter per IP address
+		s.tk.NoOpCounter = 0
+		for s.tk.NoOpCounter < noop {
+			s.tk.NoOpCounter += 1
+			s.runner.logger.Infof("NoOp Iteration %d", s.tk.NoOpCounter)
+			err = client.Noop()
+			if err != nil {
+				s.error(err)
+				break
+			}
+		}
+
+		if s.tk.NoOpCounter == noop {
+			s.runner.logger.Infof("Successfully generated no-op traffic")
+			return true
+		} else {
+			s.runner.logger.Infof("Failed no-op traffic at iteration %d", s.tk.NoOpCounter)
+			return false
+		}
+	}
+
+	return true
+}
+
+// Run implements ExperimentMeasurer.Run
+func (m Measurer) Run(
+	ctx context.Context, sess model.ExperimentSession,
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
+) error {
+	log := sess.Logger()
+	trace := measurexlite.NewTrace(0, measurement.MeasurementStartTimeSaved)
+
+	config, err := config(measurement.Input)
+	if err != nil {
+		// Invalid input data, we don't even generate report
+		return err
+	}
+
+	tk := new(TestKeys)
+	measurement.TestKeys = tk
+
+	ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
+	defer cancel()
+
+	tlsconfig := tls.Config{
+		InsecureSkipVerify: false,
+		ServerName:         config.host,
+	}
+
+	runner := &TCPRunner{
+		trace:     trace,
+		logger:    log,
+		ctx:       ctx,
+		tk:        tk,
+		tlsconfig: &tlsconfig,
+		host:      config.host,
+		port:      config.port,
+	}
+
+	// First resolve DNS
+	addrs, success := runner.resolve(config.host)
+	if !success {
+		return nil
+	}
+
+	for _, addr := range addrs {
+		tcp_session, success := runner.conn(addr, config.port)
+		if !success {
+			continue
+		}
+		defer tcp_session.Close()
+
+		if config.forced_tls {
+			// Direct TLS connection
+			if !tcp_session.handshake() {
+				continue
+			}
+
+			// Try EHLO + NoOps
+			if !tcp_session.smtp("localhost", config.noop_count) {
+				continue
+			}
+		} else {
+			// StartTLS... first try plaintext EHLO
+			if !tcp_session.smtp("localhost", 0) {
+				continue
+			}
+
+			// Upgrade via StartTLS and try EHLO + NoOps
+			if !tcp_session.starttls("STARTTLS\n") {
+				continue
+			}
+
+			if !tcp_session.smtp("localhost", config.noop_count) {
+				continue
+			}
+		}
+	}
+
+	return nil
+}
+
+// NewExperimentMeasurer creates a new ExperimentMeasurer.
+func NewExperimentMeasurer(config Config) model.ExperimentMeasurer {
+	return Measurer{Config: config}
+}
+
+// SummaryKeys contains summary keys for this experiment.
+//
+// Note that this structure is part of the ABI contract with ooniprobe
+// therefore we should be careful when changing it.
+type SummaryKeys struct {
+	//DNSBlocking bool `json:"facebook_dns_blocking"`
+	//TCPBlocking bool `json:"facebook_tcp_blocking"`
+	IsAnomaly bool `json:"-"`
+}
+
+// GetSummaryKeys implements model.ExperimentMeasurer.GetSummaryKeys.
+func (m Measurer) GetSummaryKeys(measurement *model.Measurement) (interface{}, error) {
+	sk := SummaryKeys{IsAnomaly: false}
+	_, ok := measurement.TestKeys.(*TestKeys)
+	if !ok {
+		return sk, errors.New("invalid test keys type")
+	}
+	return sk, nil
+}

internal/engine/experiment/smtp/smtp_test.go

@@ -0,0 +1,185 @@
+package smtp
+
+import (
+	"bufio"
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"strings"
+	"testing"
+
+	"github.com/ooni/probe-cli/v3/internal/engine/mockable"
+	"github.com/ooni/probe-cli/v3/internal/model"
+)
+
+func plaintextListener() net.Listener {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		if l, err = net.Listen("tcp6", "[::1]:0"); err != nil {
+			panic(fmt.Sprintf("httptest: failed to listen on a port: %v", err))
+		}
+	}
+	return l
+}
+
+func tlsListener(l net.Listener) net.Listener {
+	return tls.NewListener(l, &tls.Config{})
+}
+
+func listener_addr(l net.Listener) string {
+	return l.Addr().String()
+}
+
+func ValidSMTPServer(conn net.Conn) {
+	for {
+		command, err := bufio.NewReader(conn).ReadString('\n')
+		if err != nil {
+			return
+		}
+
+		if command == "" {
+		} else if command == "NOOP" {
+			conn.Write([]byte("250 2.0.0 Ok\n"))
+		} else if command == "STARTTLS" {
+			conn.Write([]byte("220 2.0.0 Ready to start TLS\n"))
+			// TODO: conn.Close does not actually close connection? or does client not detect it?
+			conn.Close()
+			return
+		} else if strings.HasPrefix(command, "EHLO") {
+			conn.Write([]byte("250 mock.example.com\n"))
+		}
+		conn.Write([]byte("\n"))
+	}
+}
+
+func TCPServer(l net.Listener) {
+	for {
+		conn, err := l.Accept()
+		if err != nil {
+			continue
+		}
+		defer conn.Close()
+		conn.Write([]byte("220 mock.example.com ESMTP (spam is not appreciated)\n"))
+		ValidSMTPServer(conn)
+	}
+}
+
+func TestMeasurer_run(t *testing.T) {
+	// runHelper is an helper function to run this set of tests.
+	runHelper := func(input string) (*model.Measurement, model.ExperimentMeasurer, error) {
+		m := NewExperimentMeasurer(Config{})
+		if m.ExperimentName() != "smtp" {
+			t.Fatal("invalid experiment name")
+		}
+		if m.ExperimentVersion() != "0.0.1" {
+			t.Fatal("invalid experiment version")
+		}
+		ctx := context.Background()
+		meas := &model.Measurement{
+			Input: model.MeasurementTarget(input),
+		}
+		sess := &mockable.Session{
+			MockableLogger: model.DiscardLogger,
+		}
+		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
+		err := m.Run(ctx, sess, meas, callbacks)
+		return meas, m, err
+	}
+
+	t.Run("with empty input", func(t *testing.T) {
+		_, _, err := runHelper("")
+		if !errors.Is(err, errNoInputProvided) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with invalid URL", func(t *testing.T) {
+		_, _, err := runHelper("\t")
+		if !errors.Is(err, errInputIsNotAnURL) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with invalid scheme", func(t *testing.T) {
+		_, _, err := runHelper("https://8.8.8.8:443/")
+		if !errors.Is(err, errInvalidScheme) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with broken TLS", func(t *testing.T) {
+		p := plaintextListener()
+		defer p.Close()
+
+		l := tlsListener(p)
+		defer l.Close()
+		addr := listener_addr(l)
+		go TCPServer(l)
+
+		meas, m, err := runHelper("smtps://" + addr)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		tk := meas.TestKeys.(*TestKeys)
+
+		for _, run := range tk.Runs {
+			for _, handshake := range run.TLSHandshakes {
+				if *handshake.Failure != "unknown_failure: remote error: tls: unrecognized name" {
+					t.Fatal("expected unrecognized_name in TLS handshake")
+				}
+			}
+
+			if run.NoOpCounter != 0 {
+				t.Fatalf("expected to not have any noops, not %d noops", run.NoOpCounter)
+			}
+		}
+
+		ask, err := m.GetSummaryKeys(meas)
+		if err != nil {
+			t.Fatal("cannot obtain summary")
+		}
+		summary := ask.(SummaryKeys)
+		if summary.IsAnomaly {
+			t.Fatal("expected no anomaly")
+		}
+	})
+
+	t.Run("with broken starttls", func(t *testing.T) {
+		l := plaintextListener()
+		defer l.Close()
+		addr := listener_addr(l)
+
+		go TCPServer(l)
+
+		meas, m, err := runHelper("smtp://" + addr)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		tk := meas.TestKeys.(*TestKeys)
+
+		for _, run := range tk.Runs {
+			for _, handshake := range run.TLSHandshakes {
+				if *handshake.Failure != "generic_timeout_error" {
+					t.Fatal("expected timeout in TLS handshake")
+				}
+			}
+
+			if run.NoOpCounter != 0 {
+				t.Fatalf("expected to not have any noops, not %d noops", run.NoOpCounter)
+			}
+		}
+
+		ask, err := m.GetSummaryKeys(meas)
+		if err != nil {
+			t.Fatal("cannot obtain summary")
+		}
+		summary := ask.(SummaryKeys)
+		if summary.IsAnomaly {
+			t.Fatal("expected no anomaly")
+		}
+	})
+}

internal/engine/experiment/sniblocking/sniblocking.go

@@ -233,10 +233,12 @@ func maybeURLToSNI(input model.MeasurementTarget) (model.MeasurementTarget, erro
 }
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
+	callbacks model.ExperimentCallbacks,
+) error {
 	m.mu.Lock()
 	if m.cache == nil {
 		m.cache = make(map[string]Subresult)

internal/engine/experiment/sniblocking/sniblocking_test.go

@@ -116,12 +116,12 @@ func TestMeasurerMeasureNoMeasurementInput(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{
 		ControlSNI: "example.com",
 	})
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: &model.Measurement{},
+		newsession(),
-		Session:     newsession(),
+		new(model.Measurement),
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if err.Error() != "Experiment requires measurement.Input" {
 		t.Fatal("not the error we expected")
 	}
@@ -136,12 +136,12 @@ func TestMeasurerMeasureWithInvalidInput(t *testing.T) {
 	measurement := &model.Measurement{
 		Input: "\t",
 	}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: measurement,
+		newsession(),
-		Session:     newsession(),
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(ctx, args)
+	)
 	if err == nil {
 		t.Fatal("expected an error here")
 	}
@@ -156,12 +156,12 @@ func TestMeasurerMeasureWithCancelledContext(t *testing.T) {
 	measurement := &model.Measurement{
 		Input: "kernel.org",
 	}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: measurement,
+		newsession(),
-		Session:     newsession(),
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(ctx, args)
+	)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/engine/experiment/stunreachability/stunreachability.go

@@ -73,10 +73,10 @@ var errStunMissingPortInURL = errors.New("stun: missing port in URL")
 var errUnsupportedURLScheme = errors.New("stun: unsupported URL scheme")
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	tk := new(TestKeys)
 	measurement.TestKeys = tk
 	registerExtensions(measurement)

internal/engine/experiment/stunreachability/stunreachability_test.go

@@ -32,12 +32,12 @@ func TestMeasurerExperimentNameVersion(t *testing.T) {
 func TestRunWithoutInput(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{},
-		Session:     &mockable.Session{},
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if !errors.Is(err, errStunMissingInput) {
 		t.Fatal("not the error we expected", err)
 	}
@@ -47,12 +47,12 @@ func TestRunWithInvalidURL(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("\t") // <- invalid URL
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{},
-		Session:     &mockable.Session{},
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if err == nil || !strings.HasSuffix(err.Error(), "invalid control character in URL") {
 		t.Fatal("not the error we expected", err)
 	}
@@ -62,12 +62,12 @@ func TestRunWithNoPort(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("stun://stun.ekiga.net")
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{},
-		Session:     &mockable.Session{},
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if !errors.Is(err, errStunMissingPortInURL) {
 		t.Fatal("not the error we expected", err)
 	}
@@ -77,12 +77,12 @@ func TestRunWithUnsupportedURLScheme(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget("https://stun.ekiga.net:3478")
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{},
-		Session:     &mockable.Session{},
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if !errors.Is(err, errUnsupportedURLScheme) {
 		t.Fatal("not the error we expected", err)
 	}
@@ -92,14 +92,14 @@ func TestRunWithInput(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget(defaultInput)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: model.DiscardLogger,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -124,14 +124,14 @@ func TestCancelledContext(t *testing.T) {
 	measurer := NewExperimentMeasurer(Config{})
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget(defaultInput)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: model.DiscardLogger,
 		},
-	}
+		measurement,
-	err := measurer.Run(ctx, args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if !errors.Is(err, nil) { // nil because we want to submit
 		t.Fatal("not the error we expected", err)
 	}
@@ -166,14 +166,14 @@ func TestNewClientFailure(t *testing.T) {
 	measurer := NewExperimentMeasurer(*config)
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget(defaultInput)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: model.DiscardLogger,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if !errors.Is(err, nil) { // nil because we want to submit
 		t.Fatal("not the error we expected")
 	}
@@ -202,14 +202,14 @@ func TestStartFailure(t *testing.T) {
 	measurer := NewExperimentMeasurer(*config)
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget(defaultInput)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: model.DiscardLogger,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if !errors.Is(err, nil) { // nil because we want to submit
 		t.Fatal("not the error we expected")
 	}
@@ -242,14 +242,14 @@ func TestReadFailure(t *testing.T) {
 	measurer := NewExperimentMeasurer(*config)
 	measurement := new(model.Measurement)
 	measurement.Input = model.MeasurementTarget(defaultInput)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: model.DiscardLogger,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if !errors.Is(err, nil) { // nil because we want to submit
 		t.Fatal("not the error we expected")
 	}

internal/engine/experiment/tcpping/tcpping.go

@@ -82,10 +82,12 @@ var (
 )
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
+	callbacks model.ExperimentCallbacks,
+) error {
 	if measurement.Input == "" {
 		return errNoInputProvided
 	}

internal/engine/experiment/tcpping/tcpping_test.go

@@ -51,12 +51,7 @@ func TestMeasurer_run(t *testing.T) {
 			MockableLogger: model.DiscardLogger,
 		}
 		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
-		args := &model.ExperimentArgs{
+		err := m.Run(ctx, sess, meas, callbacks)
-			Callbacks:   callbacks,
-			Measurement: meas,
-			Session:     sess,
-		}
-		err := m.Run(ctx, args)
 		return meas, m, err
 	}
 

internal/engine/experiment/telegram/telegram.go

@@ -101,11 +101,8 @@ func (m Measurer) ExperimentVersion() string {
 }
 
 // Run implements ExperimentMeasurer.Run
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(ctx context.Context, sess model.ExperimentSession,
-	callbacks := args.Callbacks
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks) error {
-	measurement := args.Measurement
-	sess := args.Session
-
 	ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
 	defer cancel()
 	urlgetter.RegisterExtensions(measurement)

internal/engine/experiment/telegram/telegram_test.go

@@ -28,14 +28,14 @@ func TestNewExperimentMeasurer(t *testing.T) {
 func TestGood(t *testing.T) {
 	measurer := telegram.NewExperimentMeasurer(telegram.Config{})
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: log.Log,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -297,12 +297,7 @@ func TestWeConfigureWebChecksToFailOnHTTPError(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	if err := measurer.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := measurer.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	if called.Load() < 1 {

internal/engine/experiment/tlsmiddlebox/measurer.go

@@ -52,10 +52,12 @@ var (
 )
 
 // // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
+	callbacks model.ExperimentCallbacks,
+) error {
 	if measurement.Input == "" {
 		return errNoInputProvided
 	}

internal/engine/experiment/tlsmiddlebox/measurer_test.go

@@ -38,12 +38,7 @@ func TestMeasurer_input_failure(t *testing.T) {
 			},
 		}
 		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
-		args := &model.ExperimentArgs{
+		err := m.Run(ctx, sess, meas, callbacks)
-			Callbacks:   callbacks,
-			Measurement: meas,
-			Session:     sess,
-		}
-		err := m.Run(ctx, args)
 		return meas, m, err
 	}
 

internal/engine/experiment/tlsping/tlsping.go

@@ -112,10 +112,12 @@ var (
 )
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
+	callbacks model.ExperimentCallbacks,
+) error {
 	if measurement.Input == "" {
 		return errNoInputProvided
 	}

internal/engine/experiment/tlsping/tlsping_test.go

@@ -58,12 +58,7 @@ func TestMeasurer_run(t *testing.T) {
 			MockableLogger: model.DiscardLogger,
 		}
 		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
-		args := &model.ExperimentArgs{
+		err := m.Run(ctx, sess, meas, callbacks)
-			Callbacks:   callbacks,
-			Measurement: meas,
-			Session:     sess,
-		}
-		err := m.Run(ctx, args)
 		return meas, m, err
 	}
 

internal/engine/experiment/tlstool/tlstool.go

@@ -78,11 +78,12 @@ var allMethods = []method{{
 }}
 
 // Run implements ExperimentMeasurer.Run.
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
-
+	callbacks model.ExperimentCallbacks,
+) error {
 	// TODO(bassosimone): wondering whether this experiment should
 	// actually be merged with sniblocking instead?
 	tk := new(TestKeys)

internal/engine/experiment/tlstool/tlstool_test.go

@@ -27,12 +27,12 @@ func TestRunWithExplicitSNI(t *testing.T) {
 	})
 	measurement := new(model.Measurement)
 	measurement.Input = "8.8.8.8:853"
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: measurement,
+		&mockable.Session{},
-		Session:     &mockable.Session{},
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(ctx, args)
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -43,12 +43,12 @@ func TestRunWithImplicitSNI(t *testing.T) {
 	measurer := tlstool.NewExperimentMeasurer(tlstool.Config{})
 	measurement := new(model.Measurement)
 	measurement.Input = "dns.google:853"
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: measurement,
+		&mockable.Session{},
-		Session:     &mockable.Session{},
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(ctx, args)
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -60,12 +60,12 @@ func TestRunWithCancelledContext(t *testing.T) {
 	measurer := tlstool.NewExperimentMeasurer(tlstool.Config{})
 	measurement := new(model.Measurement)
 	measurement.Input = "dns.google:853"
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx,
-		Measurement: measurement,
+		&mockable.Session{},
-		Session:     &mockable.Session{},
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(ctx, args)
+	)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/engine/experiment/tor/tor.go

@@ -166,10 +166,12 @@ func (m *Measurer) ExperimentVersion() string {
 }
 
 // Run implements ExperimentMeasurer.Run.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
+	callbacks model.ExperimentCallbacks,
+) error {
 	targets, err := m.gimmeTargets(ctx, sess)
 	if err != nil {
 		return err // fail the measurement if we cannot get any target

internal/engine/experiment/tor/tor_test.go

@@ -36,14 +36,14 @@ func TestMeasurerMeasureFetchTorTargetsError(t *testing.T) {
 	measurer.fetchTorTargets = func(ctx context.Context, sess model.ExperimentSession, cc string) (map[string]model.OOAPITorTarget, error) {
 		return nil, expected
 	}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: &model.Measurement{},
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: log.Log,
 		},
-	}
+		new(model.Measurement),
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if !errors.Is(err, expected) {
 		t.Fatal("not the error we expected")
 	}
@@ -55,14 +55,14 @@ func TestMeasurerMeasureFetchTorTargetsEmptyList(t *testing.T) {
 		return nil, nil
 	}
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: log.Log,
 		},
-	}
+		measurement,
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -79,14 +79,14 @@ func TestMeasurerMeasureGoodWithMockedOrchestra(t *testing.T) {
 	measurer.fetchTorTargets = func(ctx context.Context, sess model.ExperimentSession, cc string) (map[string]model.OOAPITorTarget, error) {
 		return nil, nil
 	}
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: &model.Measurement{},
+		&mockable.Session{
-		Session: &mockable.Session{
 			MockableLogger: log.Log,
 		},
-	}
+		new(model.Measurement),
-	err := measurer.Run(context.Background(), args)
+		model.NewPrinterCallbacks(log.Log),
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -99,12 +99,12 @@ func TestMeasurerMeasureGood(t *testing.T) {
 	measurer := NewMeasurer(Config{})
 	sess := newsession()
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		sess,
-		Session:     sess,
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -142,12 +142,12 @@ func TestMeasurerMeasureSanitiseOutput(t *testing.T) {
 		key: staticPrivateTestingTarget,
 	}
 	measurement := new(model.Measurement)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		context.Background(),
-		Measurement: measurement,
+		sess,
-		Session:     sess,
+		measurement,
-	}
+		model.NewPrinterCallbacks(log.Log),
-	err := measurer.Run(context.Background(), args)
+	)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/engine/experiment/torsf/integration_test.go

@@ -34,12 +34,7 @@ func TestRunWithExistingTor(t *testing.T) {
 		MockableLogger:  log.Log,
 		MockableTempDir: tempdir,
 	}
-	args := &model.ExperimentArgs{
+	if err = m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err = m.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 }

internal/engine/experiment/torsf/torsf.go

@@ -124,10 +124,10 @@ const maxRuntime = 600 * time.Second
 // set the relevant OONI error inside of the measurement and
 // return nil. This is important because the caller may not submit
 // the measurement if this method returns an error.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	ptl, sfdialer, err := m.setup(ctx, sess.Logger())
 	if err != nil {
 		// we cannot setup the experiment

internal/engine/experiment/torsf/torsf_test.go

@@ -47,12 +47,7 @@ func TestFailureWithInvalidRendezvousMethod(t *testing.T) {
 	callbacks := &model.PrinterCallbacks{
 		Logger: model.DiscardLogger,
 	}
-	args := &model.ExperimentArgs{
+	err := m.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := m.Run(ctx, args)
 	if !errors.Is(err, ptx.ErrSnowflakeNoSuchRendezvousMethod) {
 		t.Fatal("unexpected error", err)
 	}
@@ -75,12 +70,7 @@ func TestFailureToStartPTXListener(t *testing.T) {
 	callbacks := &model.PrinterCallbacks{
 		Logger: model.DiscardLogger,
 	}
-	args := &model.ExperimentArgs{
+	if err := m.Run(ctx, sess, measurement, callbacks); !errors.Is(err, expected) {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := m.Run(ctx, args); !errors.Is(err, expected) {
 		t.Fatal("not the error we expected", err)
 	}
 	if tk := measurement.TestKeys; tk != nil {
@@ -118,12 +108,7 @@ func TestSuccessWithMockedTunnelStart(t *testing.T) {
 	callbacks := &model.PrinterCallbacks{
 		Logger: model.DiscardLogger,
 	}
-	args := &model.ExperimentArgs{
+	if err := m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := m.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	if called.Load() != 1 {
@@ -183,12 +168,7 @@ func TestWithCancelledContext(t *testing.T) {
 	callbacks := &model.PrinterCallbacks{
 		Logger: model.DiscardLogger,
 	}
-	args := &model.ExperimentArgs{
+	if err := m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := m.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	tk := measurement.TestKeys.(*TestKeys)
@@ -251,12 +231,7 @@ func TestFailureToStartTunnel(t *testing.T) {
 	callbacks := &model.PrinterCallbacks{
 		Logger: model.DiscardLogger,
 	}
-	args := &model.ExperimentArgs{
+	if err := m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := m.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	tk := measurement.TestKeys.(*TestKeys)

internal/engine/experiment/urlgetter/urlgetter.go

@@ -97,10 +97,10 @@ func (m Measurer) ExperimentVersion() string {
 }
 
 // Run implements model.ExperimentSession.Run
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	// When using the urlgetter experiment directly, there is a nonconfigurable
 	// default timeout that applies. When urlgetter is used as a library, it's
 	// instead the responsibility of the user of urlgetter to set timeouts. Note

internal/engine/experiment/urlgetter/urlgetter_test.go

@@ -23,12 +23,10 @@ func TestMeasurer(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	measurement.Input = "https://www.google.com"
-	args := &model.ExperimentArgs{
+	err := m.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx, &mockable.Session{},
-		Measurement: measurement,
+		measurement, model.NewPrinterCallbacks(log.Log),
-		Session:     &mockable.Session{},
+	)
-	}
-	err := m.Run(ctx, args)
 	if !errors.Is(err, nil) { // nil because we want to submit the measurement
 		t.Fatal("not the error we expected")
 	}
@@ -62,12 +60,10 @@ func TestMeasurerDNSCache(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	measurement.Input = "https://www.google.com"
-	args := &model.ExperimentArgs{
+	err := m.Run(
-		Callbacks:   model.NewPrinterCallbacks(log.Log),
+		ctx, &mockable.Session{},
-		Measurement: measurement,
+		measurement, model.NewPrinterCallbacks(log.Log),
-		Session:     &mockable.Session{},
+	)
-	}
-	err := m.Run(ctx, args)
 	if !errors.Is(err, nil) { // nil because we want to submit the measurement
 		t.Fatal("not the error we expected")
 	}

internal/engine/experiment/vanillator/integration_test.go

@@ -34,12 +34,7 @@ func TestRunWithExistingTor(t *testing.T) {
 		MockableLogger:  log.Log,
 		MockableTempDir: tempdir,
 	}
-	args := &model.ExperimentArgs{
+	if err = m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err = m.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 }

internal/engine/experiment/vanillator/vanillator.go

@@ -106,10 +106,10 @@ const maxRuntime = 200 * time.Second
 // set the relevant OONI error inside of the measurement and
 // return nil. This is important because the caller may not submit
 // the measurement if this method returns an error.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	m.registerExtensions(measurement)
 	start := time.Now()
 	ctx, cancel := context.WithTimeout(ctx, maxRuntime)

internal/engine/experiment/vanillator/vanillator_test.go

@@ -59,12 +59,7 @@ func TestSuccessWithMockedTunnelStart(t *testing.T) {
 	callbacks := &model.PrinterCallbacks{
 		Logger: model.DiscardLogger,
 	}
-	args := &model.ExperimentArgs{
+	if err := m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := m.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	if called.Load() != 1 {
@@ -118,12 +113,7 @@ func TestWithCancelledContext(t *testing.T) {
 	callbacks := &model.PrinterCallbacks{
 		Logger: model.DiscardLogger,
 	}
-	args := &model.ExperimentArgs{
+	if err := m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := m.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	tk := measurement.TestKeys.(*TestKeys)
@@ -180,12 +170,7 @@ func TestFailureToStartTunnel(t *testing.T) {
 	callbacks := &model.PrinterCallbacks{
 		Logger: model.DiscardLogger,
 	}
-	args := &model.ExperimentArgs{
+	if err := m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := m.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	tk := measurement.TestKeys.(*TestKeys)

internal/engine/experiment/webconnectivity/control.go

@@ -4,10 +4,9 @@ import (
 	"context"
 
 	"github.com/ooni/probe-cli/v3/internal/geoipx"
-	"github.com/ooni/probe-cli/v3/internal/httpapi"
+	"github.com/ooni/probe-cli/v3/internal/httpx"
 	"github.com/ooni/probe-cli/v3/internal/model"
 	"github.com/ooni/probe-cli/v3/internal/netxlite"
-	"github.com/ooni/probe-cli/v3/internal/runtimex"
 )
 
 // Redirect to types defined inside the model package
@@ -22,23 +21,22 @@ type (
 // Control performs the control request and returns the response.
 func Control(
 	ctx context.Context, sess model.ExperimentSession,
-	testhelpers []model.OOAPIService, creq ControlRequest) (ControlResponse, *model.OOAPIService, error) {
+	thAddr string, creq ControlRequest) (out ControlResponse, err error) {
-	seqCaller := httpapi.NewSequenceCaller(
+	clnt := &httpx.APIClientTemplate{
-		httpapi.MustNewPOSTJSONWithJSONResponseDescriptor(sess.Logger(), "/", creq).WithBodyLogging(true),
+		BaseURL:    thAddr,
-		httpapi.NewEndpointList(sess.DefaultHTTPClient(), sess.UserAgent(), testhelpers...)...,
+		HTTPClient: sess.DefaultHTTPClient(),
-	)
+		Logger:     sess.Logger(),
-	sess.Logger().Infof("control for %s...", creq.HTTPRequest)
+		UserAgent:  sess.UserAgent(),
-	var out ControlResponse
-	idx, err := seqCaller.CallWithJSONResponse(ctx, &out)
-	sess.Logger().Infof("control for %s... %+v", creq.HTTPRequest, model.ErrorToStringOrOK(err))
-	if err != nil {
-		// make sure error is wrapped
-		err = netxlite.NewTopLevelGenericErrWrapper(err)
-		return ControlResponse{}, nil, err
 	}
+	sess.Logger().Infof("control for %s...", creq.HTTPRequest)
+	// make sure error is wrapped
+	err = clnt.WithBodyLogging().Build().PostJSON(ctx, "/", creq, &out)
+	if err != nil {
+		err = netxlite.NewTopLevelGenericErrWrapper(err)
+	}
+	sess.Logger().Infof("control for %s... %+v", creq.HTTPRequest, model.ErrorToStringOrOK(err))
 	fillASNs(&out.DNS)
-	runtimex.Assert(idx >= 0 && idx < len(testhelpers), "idx out of bounds")
+	return
-	return out, &testhelpers[idx], nil
 }
 
 // fillASNs fills the ASNs array of ControlDNSResult. For each Addr inside

internal/engine/experiment/webconnectivity/webconnectivity.go

@@ -15,7 +15,7 @@ import (
 
 const (
 	testName    = "web_connectivity"
-	testVersion = "0.4.2"
+	testVersion = "0.4.1"
 )
 
 // Config contains the experiment config.
@@ -121,11 +121,12 @@ const (
 )
 
 // Run implements ExperimentMeasurer.Run.
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context,
-	measurement := args.Measurement
+	sess model.ExperimentSession,
-	sess := args.Session
+	measurement *model.Measurement,
-
+	callbacks model.ExperimentCallbacks,
+) error {
 	ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
 	defer cancel()
 	tk := new(TestKeys)
@@ -144,9 +145,19 @@ func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
 	}
 	// 1. find test helper
 	testhelpers, _ := sess.GetTestHelpersByName("web-connectivity")
-	if len(testhelpers) < 1 {
+	var testhelper *model.OOAPIService
+	for _, th := range testhelpers {
+		if th.Type == "https" {
+			testhelper = &th
+			break
+		}
+	}
+	if testhelper == nil {
 		return ErrNoAvailableTestHelpers
 	}
+	measurement.TestHelpers = map[string]interface{}{
+		"backend": testhelper,
+	}
 	// 2. perform the DNS lookup step
 	dnsBegin := time.Now()
 	dnsResult := DNSLookup(ctx, DNSLookupConfig{
@@ -156,11 +167,10 @@ func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
 	tk.Queries = append(tk.Queries, dnsResult.TestKeys.Queries...)
 	tk.DNSExperimentFailure = dnsResult.Failure
 	epnts := NewEndpoints(URL, dnsResult.Addresses())
-	sess.Logger().Infof("using control: %+v", testhelpers)
+	sess.Logger().Infof("using control: %s", testhelper.Address)
 	// 3. perform the control measurement
 	thBegin := time.Now()
-	var usedTH *model.OOAPIService
+	tk.Control, err = Control(ctx, sess, testhelper.Address, ControlRequest{
-	tk.Control, usedTH, err = Control(ctx, sess, testhelpers, ControlRequest{
 		HTTPRequest: URL.String(),
 		HTTPRequestHeaders: map[string][]string{
 			"Accept":          {model.HTTPHeaderAccept},
@@ -169,11 +179,6 @@ func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
 		},
 		TCPConnect: epnts.Endpoints(),
 	})
-	if usedTH != nil {
-		measurement.TestHelpers = map[string]interface{}{
-			"backend": usedTH,
-		}
-	}
 	tk.THRuntime = time.Since(thBegin)
 	tk.ControlFailure = tracex.NewFailure(err)
 	// 4. analyze DNS results

internal/engine/experiment/webconnectivity/webconnectivity_test.go

@@ -21,7 +21,7 @@ func TestNewExperimentMeasurer(t *testing.T) {
 	if measurer.ExperimentName() != "web_connectivity" {
 		t.Fatal("unexpected name")
 	}
-	if measurer.ExperimentVersion() != "0.4.2" {
+	if measurer.ExperimentVersion() != "0.4.1" {
 		t.Fatal("unexpected version")
 	}
 }
@@ -37,12 +37,7 @@ func TestSuccess(t *testing.T) {
 	sess := newsession(t, true)
 	measurement := &model.Measurement{Input: "http://www.example.com"}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -70,12 +65,7 @@ func TestMeasureWithCancelledContext(t *testing.T) {
 	sess := newsession(t, true)
 	measurement := &model.Measurement{Input: "http://www.example.com"}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	if err := measurer.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := measurer.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	tk := measurement.TestKeys.(*webconnectivity.TestKeys)
@@ -109,12 +99,7 @@ func TestMeasureWithNoInput(t *testing.T) {
 	sess := newsession(t, true)
 	measurement := &model.Measurement{Input: ""}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, webconnectivity.ErrNoInput) {
 		t.Fatal(err)
 	}
@@ -142,12 +127,7 @@ func TestMeasureWithInputNotBeingAnURL(t *testing.T) {
 	sess := newsession(t, true)
 	measurement := &model.Measurement{Input: "\t\t\t\t\t\t"}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, webconnectivity.ErrInputIsNotAnURL) {
 		t.Fatal(err)
 	}
@@ -175,12 +155,7 @@ func TestMeasureWithUnsupportedInput(t *testing.T) {
 	sess := newsession(t, true)
 	measurement := &model.Measurement{Input: "dnslookup://example.com"}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, webconnectivity.ErrUnsupportedInput) {
 		t.Fatal(err)
 	}
@@ -208,12 +183,7 @@ func TestMeasureWithNoAvailableTestHelpers(t *testing.T) {
 	sess := newsession(t, false)
 	measurement := &model.Measurement{Input: "https://www.example.com"}
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if !errors.Is(err, webconnectivity.ErrNoAvailableTestHelpers) {
 		t.Fatal(err)
 	}

internal/engine/experiment/whatsapp/whatsapp.go

@@ -154,11 +154,10 @@ func (m Measurer) ExperimentVersion() string {
 }
 
 // Run implements ExperimentMeasurer.Run
-func (m Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
-
 	ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
 	defer cancel()
 	urlgetter.RegisterExtensions(measurement)

internal/engine/experiment/whatsapp/whatsapp_test.go

@@ -35,12 +35,7 @@ func TestSuccess(t *testing.T) {
 	sess := &mockable.Session{MockableLogger: log.Log}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -75,12 +70,7 @@ func TestFailureAllEndpoints(t *testing.T) {
 	sess := &mockable.Session{MockableLogger: log.Log}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	err := measurer.Run(ctx, sess, measurement, callbacks)
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	err := measurer.Run(ctx, args)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -608,12 +598,7 @@ func TestWeConfigureWebChecksCorrectly(t *testing.T) {
 	}
 	measurement := new(model.Measurement)
 	callbacks := model.NewPrinterCallbacks(log.Log)
-	args := &model.ExperimentArgs{
+	if err := measurer.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err := measurer.Run(ctx, args); err != nil {
 		t.Fatal(err)
 	}
 	if called.Load() != 263 {

internal/engine/experiment_integration_test.go

@@ -475,7 +475,10 @@ func (am *antaniMeasurer) ExperimentVersion() string {
 	return "0.1.1"
 }
 
-func (am *antaniMeasurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (am *antaniMeasurer) Run(
+	ctx context.Context, sess model.ExperimentSession,
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
+) error {
 	return nil
 }
 

internal/experiment/webconnectivity/cleartextflow.go

@@ -285,7 +285,7 @@ func (t *CleartextFlow) maybeFollowRedirects(ctx context.Context, resp *http.Res
 			WaitGroup:    t.WaitGroup,
 			Referer:      resp.Request.URL.String(),
 			Session:      nil, // no need to issue another control request
-			TestHelpers:  nil, // ditto
+			THAddr:       "",  // ditto
 			UDPAddress:   t.UDPAddress,
 		}
 		resolvers.Start(ctx)

internal/experiment/webconnectivity/control.go

@@ -8,11 +8,10 @@ import (
 	"time"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/experiment/webconnectivity"
-	"github.com/ooni/probe-cli/v3/internal/httpapi"
+	"github.com/ooni/probe-cli/v3/internal/httpx"
 	"github.com/ooni/probe-cli/v3/internal/measurexlite"
 	"github.com/ooni/probe-cli/v3/internal/model"
 	"github.com/ooni/probe-cli/v3/internal/netxlite"
-	"github.com/ooni/probe-cli/v3/internal/runtimex"
 )
 
 // EndpointMeasurementsStarter is used by Control to start extra
@@ -52,8 +51,8 @@ type Control struct {
 	// Session is the MANDATORY session to use.
 	Session model.ExperimentSession
 
-	// TestHelpers is the MANDATORY list of test helpers.
+	// THAddr is the MANDATORY TH's URL.
-	TestHelpers []model.OOAPIService
+	THAddr string
 
 	// URL is the MANDATORY URL we are measuring.
 	URL *url.URL
@@ -103,20 +102,26 @@ func (c *Control) Run(parentCtx context.Context) {
 	// create logger for this operation
 	ol := measurexlite.NewOperationLogger(
 		c.Logger,
-		"control for %s using %+v",
+		"control for %s using %s",
 		creq.HTTPRequest,
-		c.TestHelpers,
+		c.THAddr,
 	)
 
-	// create an httpapi sequence caller
+	// create an API client
-	seqCaller := httpapi.NewSequenceCaller(
+	clnt := (&httpx.APIClientTemplate{
-		httpapi.MustNewPOSTJSONWithJSONResponseDescriptor(c.Logger, "/", creq).WithBodyLogging(true),
+		Accept:        "",
-		httpapi.NewEndpointList(c.Session.DefaultHTTPClient(), c.Session.UserAgent(), c.TestHelpers...)...,
+		Authorization: "",
-	)
+		BaseURL:       c.THAddr,
+		HTTPClient:    c.Session.DefaultHTTPClient(),
+		Host:          "", // use the one inside the URL
+		LogBody:       true,
+		Logger:        c.Logger,
+		UserAgent:     c.Session.UserAgent(),
+	}).Build()
 
 	// issue the control request and wait for the response
 	var cresp webconnectivity.ControlResponse
-	idx, err := seqCaller.CallWithJSONResponse(opCtx, &cresp)
+	err := clnt.PostJSON(opCtx, "/", creq, &cresp)
 	if err != nil {
 		// make sure error is wrapped
 		err = netxlite.NewTopLevelGenericErrWrapper(err)
@@ -129,10 +134,6 @@ func (c *Control) Run(parentCtx context.Context) {
 	c.TestKeys.SetControl(&cresp)
 	ol.Stop(nil)
 
-	// record the specific TH that worked
-	runtimex.Assert(idx >= 0 && idx < len(c.TestHelpers), "idx out of bounds")
-	c.TestKeys.setTestHelper(&c.TestHelpers[idx])
-
 	// if the TH returned us addresses we did not previously were
 	// aware of, make sure we also measure them
 	c.maybeStartExtraMeasurements(parentCtx, cresp.DNS.Addrs)

internal/experiment/webconnectivity/dnsresolvers.go

@@ -67,9 +67,8 @@ type DNSResolvers struct {
 	// always follow the redirect chain caused by the provided URL.
 	Session model.ExperimentSession
 
-	// TestHelpers is the OPTIONAL list of test helpers. If the list is
+	// THAddr is the OPTIONAL test helper address.
-	// empty, we are not going to try to contact any test helper.
+	THAddr string
-	TestHelpers []model.OOAPIService
 
 	// UDPAddress is the OPTIONAL address of the UDP resolver to use. If this
 	// field is not set we use a default one (e.g., `8.8.8.8:53`).
@@ -499,15 +498,15 @@ func (t *DNSResolvers) startSecureFlows(
 	}
 }
 
-// maybeStartControlFlow starts the control flow iff .Session and .TestHelpers are set.
+// maybeStartControlFlow starts the control flow iff .Session and .THAddr are set.
 func (t *DNSResolvers) maybeStartControlFlow(
 	ctx context.Context,
 	ps *prioritySelector,
 	addresses []DNSEntry,
 ) {
-	// note: for subsequent requests we don't set .Session and .TestHelpers hence
+	// note: for subsequent requests we don't set .Session and .THAddr hence
 	// we are not going to query the test helper more than once
-	if t.Session != nil && len(t.TestHelpers) > 0 {
+	if t.Session != nil && t.THAddr != "" {
 		var addrs []string
 		for _, addr := range addresses {
 			addrs = append(addrs, addr.Addr)
@@ -519,7 +518,7 @@ func (t *DNSResolvers) maybeStartControlFlow(
 			PrioSelector:             ps,
 			TestKeys:                 t.TestKeys,
 			Session:                  t.Session,
-			TestHelpers:              t.TestHelpers,
+			THAddr:                   t.THAddr,
 			URL:                      t.URL,
 			WaitGroup:                t.WaitGroup,
 		}

internal/experiment/webconnectivity/measurer.go

@@ -36,17 +36,15 @@ func (m *Measurer) ExperimentName() string {
 
 // ExperimentVersion implements model.ExperimentMeasurer.
 func (m *Measurer) ExperimentVersion() string {
-	return "0.5.19"
+	return "0.5.18"
 }
 
 // Run implements model.ExperimentMeasurer.
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(ctx context.Context, sess model.ExperimentSession,
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks) error {
 	// Reminder: when this function returns an error, the measurement result
 	// WILL NOT be submitted to the OONI backend. You SHOULD only return an error
 	// for fundamental errors (e.g., the input is invalid or missing).
-	_ = args.Callbacks
-	measurement := args.Measurement
-	sess := args.Session
 
 	// make sure we have a cancellable context such that we can stop any
 	// goroutine running in the background (e.g., priority.go's ones)
@@ -91,7 +89,17 @@ func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
 
 	// obtain the test helper's address
 	testhelpers, _ := sess.GetTestHelpersByName("web-connectivity")
-	if len(testhelpers) < 1 {
+	var thAddr string
+	for _, th := range testhelpers {
+		if th.Type == "https" {
+			thAddr = th.Address
+			measurement.TestHelpers = map[string]any{
+				"backend": &th,
+			}
+			break
+		}
+	}
+	if thAddr == "" {
 		sess.Logger().Warnf("continuing without a valid TH address")
 		tk.SetControlFailure(webconnectivity.ErrNoAvailableTestHelpers)
 	}
@@ -112,7 +120,7 @@ func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
 		CookieJar:    jar,
 		Referer:      "",
 		Session:      sess,
-		TestHelpers:  testhelpers,
+		THAddr:       thAddr,
 		UDPAddress:   "",
 	}
 	resos.Start(ctx)
@@ -129,16 +137,6 @@ func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
 	// perform any deferred computation on the test keys
 	tk.Finalize(sess.Logger())
 
-	// set the test helper we used
-	// TODO(bassosimone): it may be more informative to know about all the
-	// test helpers we _tried_ to use, however the data format does not have
-	// support for that as far as I can tell...
-	if th := tk.getTestHelper(); th != nil {
-		measurement.TestHelpers = map[string]interface{}{
-			"backend": th,
-		}
-	}
-
 	// return whether there was a fundamental failure, which would prevent
 	// the measurement from being submitted to the OONI collector.
 	return tk.fundamentalFailure

internal/experiment/webconnectivity/secureflow.go

@@ -337,7 +337,7 @@ func (t *SecureFlow) maybeFollowRedirects(ctx context.Context, resp *http.Respon
 			WaitGroup:    t.WaitGroup,
 			Referer:      resp.Request.URL.String(),
 			Session:      nil, // no need to issue another control request
-			TestHelpers:  nil, // ditto
+			THAddr:       "",  // ditto
 			UDPAddress:   t.UDPAddress,
 		}
 		resolvers.Start(ctx)

internal/experiment/webconnectivity/testkeys.go

@@ -134,10 +134,6 @@ type TestKeys struct {
 
 	// mu provides mutual exclusion for accessing the test keys.
 	mu *sync.Mutex
-
-	// testHelper is used to communicate the TH that worked to the main
-	// goroutine such that we can fill measurement.TestHelpers.
-	testHelper *model.OOAPIService
 }
 
 // ConnPriorityLogEntry is an entry in the TestKeys.ConnPriorityLog slice.
@@ -306,21 +302,6 @@ func (tk *TestKeys) AppendConnPriorityLogEntry(entry *ConnPriorityLogEntry) {
 	tk.mu.Unlock()
 }
 
-// setTestHelper sets .testHelper in a thread safe way
-func (tk *TestKeys) setTestHelper(th *model.OOAPIService) {
-	tk.mu.Lock()
-	tk.testHelper = th
-	tk.mu.Unlock()
-}
-
-// getTestHelper gets .testHelper in a thread safe way
-func (tk *TestKeys) getTestHelper() (th *model.OOAPIService) {
-	tk.mu.Lock()
-	th = tk.testHelper
-	tk.mu.Unlock()
-	return
-}
-
 // NewTestKeys creates a new instance of TestKeys.
 func NewTestKeys() *TestKeys {
 	return &TestKeys{
@@ -367,7 +348,6 @@ func NewTestKeys() *TestKeys {
 		ControlRequest:        nil,
 		fundamentalFailure:    nil,
 		mu:                    &sync.Mutex{},
-		testHelper:            nil,
 	}
 }
 

internal/httpapi/call.go

@@ -1,181 +0,0 @@
-package httpapi
-
-//
-// Calling HTTP APIs.
-//
-
-import (
-	"bytes"
-	"context"
-	"encoding/json"
-	"fmt"
-	"io"
-	"net/http"
-	"net/url"
-	"strings"
-
-	"github.com/ooni/probe-cli/v3/internal/netxlite"
-)
-
-// joinURLPath appends |resourcePath| to |urlPath|.
-func joinURLPath(urlPath, resourcePath string) string {
-	if resourcePath == "" {
-		if urlPath == "" {
-			return "/"
-		}
-		return urlPath
-	}
-	if !strings.HasSuffix(urlPath, "/") {
-		urlPath += "/"
-	}
-	resourcePath = strings.TrimPrefix(resourcePath, "/")
-	return urlPath + resourcePath
-}
-
-// newRequest creates a new http.Request from the given |ctx|, |endpoint|, and |desc|.
-func newRequest(ctx context.Context, endpoint *Endpoint, desc *Descriptor) (*http.Request, error) {
-	URL, err := url.Parse(endpoint.BaseURL)
-	if err != nil {
-		return nil, err
-	}
-	// BaseURL and resource URL are joined if they have a path
-	URL.Path = joinURLPath(URL.Path, desc.URLPath)
-	if len(desc.URLQuery) > 0 {
-		URL.RawQuery = desc.URLQuery.Encode()
-	} else {
-		URL.RawQuery = "" // as documented we only honour desc.URLQuery
-	}
-	var reqBody io.Reader
-	if len(desc.RequestBody) > 0 {
-		reqBody = bytes.NewReader(desc.RequestBody)
-		desc.Logger.Debugf("httpapi: request body length: %d", len(desc.RequestBody))
-		if desc.LogBody {
-			desc.Logger.Debugf("httpapi: request body: %s", string(desc.RequestBody))
-		}
-	}
-	request, err := http.NewRequestWithContext(ctx, desc.Method, URL.String(), reqBody)
-	if err != nil {
-		return nil, err
-	}
-	request.Host = endpoint.Host // allow cloudfronting
-	if desc.Authorization != "" {
-		request.Header.Set("Authorization", desc.Authorization)
-	}
-	if desc.ContentType != "" {
-		request.Header.Set("Content-Type", desc.ContentType)
-	}
-	if desc.Accept != "" {
-		request.Header.Set("Accept", desc.Accept)
-	}
-	if endpoint.UserAgent != "" {
-		request.Header.Set("User-Agent", endpoint.UserAgent)
-	}
-	return request, nil
-}
-
-// ErrHTTPRequestFailed indicates that the server returned >= 400.
-type ErrHTTPRequestFailed struct {
-	// StatusCode is the status code that failed.
-	StatusCode int
-}
-
-// Error implements error.
-func (err *ErrHTTPRequestFailed) Error() string {
-	return fmt.Sprintf("httpapi: http request failed: %d", err.StatusCode)
-}
-
-// errMaybeCensorship indicates that there was an error at the networking layer
-// including, e.g., DNS, TCP connect, TLS. When we see this kind of error, we
-// will consider retrying with another endpoint under the assumption that it
-// may be that the current endpoint is censored.
-type errMaybeCensorship struct {
-	// Err is the underlying error
-	Err error
-}
-
-// Error implements error
-func (err *errMaybeCensorship) Error() string {
-	return err.Err.Error()
-}
-
-// Unwrap allows to get the underlying error
-func (err *errMaybeCensorship) Unwrap() error {
-	return err.Err
-}
-
-// docall calls the API represented by the given request |req| on the given |endpoint|
-// and returns the response and its body or an error.
-func docall(endpoint *Endpoint, desc *Descriptor, request *http.Request) (*http.Response, []byte, error) {
-	// Implementation note: remember to mark errors for which you want
-	// to retry with another endpoint using errMaybeCensorship.
-	response, err := endpoint.HTTPClient.Do(request)
-	if err != nil {
-		return nil, nil, &errMaybeCensorship{err}
-	}
-	defer response.Body.Close()
-	// Implementation note: always read and log the response body since
-	// it's quite useful to see the response JSON on API error.
-	r := io.LimitReader(response.Body, DefaultMaxBodySize)
-	data, err := netxlite.ReadAllContext(request.Context(), r)
-	if err != nil {
-		return response, nil, &errMaybeCensorship{err}
-	}
-	desc.Logger.Debugf("httpapi: response body length: %d bytes", len(data))
-	if desc.LogBody {
-		desc.Logger.Debugf("httpapi: response body: %s", string(data))
-	}
-	if response.StatusCode >= 400 {
-		return response, nil, &ErrHTTPRequestFailed{response.StatusCode}
-	}
-	return response, data, nil
-}
-
-// call is like Call but also returns the response.
-func call(ctx context.Context, desc *Descriptor, endpoint *Endpoint) (*http.Response, []byte, error) {
-	timeout := desc.Timeout
-	if timeout <= 0 {
-		timeout = DefaultCallTimeout // as documented
-	}
-	ctx, cancel := context.WithTimeout(ctx, timeout)
-	defer cancel()
-	request, err := newRequest(ctx, endpoint, desc)
-	if err != nil {
-		return nil, nil, err
-	}
-	return docall(endpoint, desc, request)
-}
-
-// Call invokes the API described by |desc| on the given HTTP |endpoint| and
-// returns the response body (as a slice of bytes) or an error.
-//
-// Note: this function returns ErrHTTPRequestFailed if the HTTP status code is
-// greater or equal than 400. You could use errors.As to obtain a copy of the
-// error that was returned and see for yourself the actual status code.
-func Call(ctx context.Context, desc *Descriptor, endpoint *Endpoint) ([]byte, error) {
-	_, rawResponseBody, err := call(ctx, desc, endpoint)
-	return rawResponseBody, err
-}
-
-// goodContentTypeForJSON tracks known-good content-types for JSON. If the content-type
-// is not in this map, |CallWithJSONResponse| emits a warning message.
-var goodContentTypeForJSON = map[string]bool{
-	applicationJSON: true,
-}
-
-// CallWithJSONResponse is like Call but also assumes that the response is a
-// JSON body and attempts to parse it into the |response| field.
-//
-// Note: this function returns ErrHTTPRequestFailed if the HTTP status code is
-// greater or equal than 400. You could use errors.As to obtain a copy of the
-// error that was returned and see for yourself the actual status code.
-func CallWithJSONResponse(ctx context.Context, desc *Descriptor, endpoint *Endpoint, response any) error {
-	httpResp, rawRespBody, err := call(ctx, desc, endpoint)
-	if err != nil {
-		return err
-	}
-	if ctype := httpResp.Header.Get("Content-Type"); !goodContentTypeForJSON[ctype] {
-		desc.Logger.Warnf("httpapi: unexpected content-type: %s", ctype)
-		// fallthrough
-	}
-	return json.Unmarshal(rawRespBody, response)
-}

internal/httpapi/descriptor.go

@@ -1,155 +0,0 @@
-package httpapi
-
-//
-// HTTP API descriptor (e.g., GET /api/v1/test-list/urls)
-//
-
-import (
-	"encoding/json"
-	"net/http"
-	"net/url"
-	"time"
-
-	"github.com/ooni/probe-cli/v3/internal/model"
-	"github.com/ooni/probe-cli/v3/internal/runtimex"
-)
-
-// Descriptor contains the parameters for calling a given HTTP
-// API (e.g., GET /api/v1/test-list/urls).
-//
-// The zero value of this struct is invalid. Please, fill all the
-// fields marked as MANDATORY for correct initialization.
-type Descriptor struct {
-	// Accept contains the OPTIONAL accept header.
-	Accept string
-
-	// Authorization is the OPTIONAL authorization.
-	Authorization string
-
-	// ContentType is the OPTIONAL content-type header.
-	ContentType string
-
-	// LogBody OPTIONALLY enables logging bodies.
-	LogBody bool
-
-	// Logger is the MANDATORY logger to use.
-	//
-	// For example, model.DiscardLogger.
-	Logger model.Logger
-
-	// MaxBodySize is the OPTIONAL maximum response body size. If
-	// not set, we use the |DefaultMaxBodySize| constant.
-	MaxBodySize int64
-
-	// Method is the MANDATORY request method.
-	Method string
-
-	// RequestBody is the OPTIONAL request body.
-	RequestBody []byte
-
-	// Timeout is the OPTIONAL timeout for this call. If no timeout
-	// is specified we will use the |DefaultCallTimeout| const.
-	Timeout time.Duration
-
-	// URLPath is the MANDATORY URL path.
-	URLPath string
-
-	// URLQuery is the OPTIONAL query.
-	URLQuery url.Values
-}
-
-// WithBodyLogging returns a SHALLOW COPY of |Descriptor| with LogBody set to |value|. You SHOULD
-// only use this method when initializing the descriptor you want to use.
-func (desc *Descriptor) WithBodyLogging(value bool) *Descriptor {
-	out := &Descriptor{}
-	*out = *desc
-	out.LogBody = value
-	return out
-}
-
-// DefaultMaxBodySize is the default value for the maximum
-// body size you can fetch using the httpapi package.
-const DefaultMaxBodySize = 1 << 22
-
-// DefaultCallTimeout is the default timeout for an httpapi call.
-const DefaultCallTimeout = 60 * time.Second
-
-// NewGETJSONDescriptor is a convenience factory for creating a new descriptor
-// that uses the GET method and expects a JSON response.
-func NewGETJSONDescriptor(logger model.Logger, urlPath string) *Descriptor {
-	return NewGETJSONWithQueryDescriptor(logger, urlPath, url.Values{})
-}
-
-// applicationJSON is the content-type for JSON
-const applicationJSON = "application/json"
-
-// NewGETJSONWithQueryDescriptor is like NewGETJSONDescriptor but it also
-// allows you to provide |query| arguments. Leaving |query| nil or empty
-// is equivalent to calling NewGETJSONDescriptor directly.
-func NewGETJSONWithQueryDescriptor(logger model.Logger, urlPath string, query url.Values) *Descriptor {
-	return &Descriptor{
-		Accept:        applicationJSON,
-		Authorization: "",
-		ContentType:   "",
-		LogBody:       false,
-		Logger:        logger,
-		MaxBodySize:   DefaultMaxBodySize,
-		Method:        http.MethodGet,
-		RequestBody:   nil,
-		Timeout:       DefaultCallTimeout,
-		URLPath:       urlPath,
-		URLQuery:      query,
-	}
-}
-
-// NewPOSTJSONWithJSONResponseDescriptor creates a descriptor that POSTs a JSON document
-// and expects to receive back a JSON document from the API.
-//
-// This function ONLY fails if we cannot serialize the |request| to JSON. So, if you know
-// that |request| is JSON-serializable, you can safely call MustNewPostJSONWithJSONResponseDescriptor instead.
-func NewPOSTJSONWithJSONResponseDescriptor(logger model.Logger, urlPath string, request any) (*Descriptor, error) {
-	rawRequest, err := json.Marshal(request)
-	if err != nil {
-		return nil, err
-	}
-	desc := &Descriptor{
-		Accept:        applicationJSON,
-		Authorization: "",
-		ContentType:   applicationJSON,
-		LogBody:       false,
-		Logger:        logger,
-		MaxBodySize:   DefaultMaxBodySize,
-		Method:        http.MethodPost,
-		RequestBody:   rawRequest,
-		Timeout:       DefaultCallTimeout,
-		URLPath:       urlPath,
-		URLQuery:      nil,
-	}
-	return desc, nil
-}
-
-// MustNewPOSTJSONWithJSONResponseDescriptor is like NewPOSTJSONWithJSONResponseDescriptor except that
-// it panics in case it's not possible to JSON serialize the |request|.
-func MustNewPOSTJSONWithJSONResponseDescriptor(logger model.Logger, urlPath string, request any) *Descriptor {
-	desc, err := NewPOSTJSONWithJSONResponseDescriptor(logger, urlPath, request)
-	runtimex.PanicOnError(err, "NewPOSTJSONWithJSONResponseDescriptor failed")
-	return desc
-}
-
-// NewGETResourceDescriptor creates a generic descriptor for GETting a
-// resource of unspecified type using the given |urlPath|.
-func NewGETResourceDescriptor(logger model.Logger, urlPath string) *Descriptor {
-	return &Descriptor{
-		Accept:        "",
-		Authorization: "",
-		ContentType:   "",
-		LogBody:       false,
-		Logger:        logger,
-		MaxBodySize:   DefaultMaxBodySize,
-		Method:        http.MethodGet,
-		RequestBody:   nil,
-		Timeout:       DefaultCallTimeout,
-		URLPath:       urlPath,
-		URLQuery:      url.Values{},
-	}
-}

internal/httpapi/descriptor_test.go

@@ -1,248 +0,0 @@
-package httpapi
-
-import (
-	"log"
-	"net/http"
-	"net/url"
-	"testing"
-	"time"
-
-	"github.com/google/go-cmp/cmp"
-	"github.com/ooni/probe-cli/v3/internal/model"
-)
-
-func TestDescriptor_WithBodyLogging(t *testing.T) {
-	type fields struct {
-		Accept        string
-		Authorization string
-		ContentType   string
-		LogBody       bool
-		Logger        model.Logger
-		MaxBodySize   int64
-		Method        string
-		RequestBody   []byte
-		Timeout       time.Duration
-		URLPath       string
-		URLQuery      url.Values
-	}
-	tests := []struct {
-		name   string
-		fields fields
-		want   *Descriptor
-	}{{
-		name:   "with empty fields",
-		fields: fields{}, // LogBody defaults to false
-		want: &Descriptor{
-			LogBody: true,
-		},
-	}, {
-		name: "with nonempty fields",
-		fields: fields{
-			Accept:        "xx",
-			Authorization: "y",
-			ContentType:   "zzz",
-			LogBody:       false, // obviously must be false
-			Logger:        model.DiscardLogger,
-			MaxBodySize:   123,
-			Method:        "POST",
-			RequestBody:   []byte("123"),
-			Timeout:       15555,
-			URLPath:       "/",
-			URLQuery: map[string][]string{
-				"a": {"b"},
-			},
-		},
-		want: &Descriptor{
-			Accept:        "xx",
-			Authorization: "y",
-			ContentType:   "zzz",
-			LogBody:       true,
-			Logger:        model.DiscardLogger,
-			MaxBodySize:   123,
-			Method:        "POST",
-			RequestBody:   []byte("123"),
-			Timeout:       15555,
-			URLPath:       "/",
-			URLQuery: map[string][]string{
-				"a": {"b"},
-			},
-		},
-	}}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			desc := &Descriptor{
-				Accept:        tt.fields.Accept,
-				Authorization: tt.fields.Authorization,
-				ContentType:   tt.fields.ContentType,
-				LogBody:       tt.fields.LogBody,
-				Logger:        tt.fields.Logger,
-				MaxBodySize:   tt.fields.MaxBodySize,
-				Method:        tt.fields.Method,
-				RequestBody:   tt.fields.RequestBody,
-				Timeout:       tt.fields.Timeout,
-				URLPath:       tt.fields.URLPath,
-				URLQuery:      tt.fields.URLQuery,
-			}
-			got := desc.WithBodyLogging(true)
-			if diff := cmp.Diff(tt.want, got); diff != "" {
-				t.Fatal(diff)
-			}
-		})
-	}
-}
-
-func TestNewGetJSONDescriptor(t *testing.T) {
-	expected := &Descriptor{
-		Accept:        "application/json",
-		Authorization: "",
-		ContentType:   "",
-		LogBody:       false,
-		Logger:        model.DiscardLogger,
-		MaxBodySize:   DefaultMaxBodySize,
-		Method:        http.MethodGet,
-		RequestBody:   nil,
-		Timeout:       DefaultCallTimeout,
-		URLPath:       "/robots.txt",
-		URLQuery:      url.Values{},
-	}
-	got := NewGETJSONDescriptor(model.DiscardLogger, "/robots.txt")
-	if diff := cmp.Diff(expected, got); diff != "" {
-		t.Fatal(diff)
-	}
-}
-
-func TestNewGetJSONWithQueryDescriptor(t *testing.T) {
-	query := url.Values{
-		"a": {"b"},
-		"c": {"d"},
-	}
-	expected := &Descriptor{
-		Accept:        "application/json",
-		Authorization: "",
-		ContentType:   "",
-		LogBody:       false,
-		Logger:        model.DiscardLogger,
-		MaxBodySize:   DefaultMaxBodySize,
-		Method:        http.MethodGet,
-		RequestBody:   nil,
-		Timeout:       DefaultCallTimeout,
-		URLPath:       "/robots.txt",
-		URLQuery:      query,
-	}
-	got := NewGETJSONWithQueryDescriptor(model.DiscardLogger, "/robots.txt", query)
-	if diff := cmp.Diff(expected, got); diff != "" {
-		t.Fatal(diff)
-	}
-}
-
-func TestNewPOSTJSONWithJSONResponseDescriptor(t *testing.T) {
-	type request struct {
-		Name string
-		Age  int64
-	}
-
-	t.Run("with failure", func(t *testing.T) {
-		request := make(chan int64)
-		got, err := NewPOSTJSONWithJSONResponseDescriptor(model.DiscardLogger, "/robots.txt", request)
-		if err == nil || err.Error() != "json: unsupported type: chan int64" {
-			log.Fatal("unexpected err", err)
-		}
-		if got != nil {
-			log.Fatal("expected to get a nil Descriptor")
-		}
-	})
-
-	t.Run("with success", func(t *testing.T) {
-		request := request{
-			Name: "sbs",
-			Age:  99,
-		}
-		expected := &Descriptor{
-			Accept:        "application/json",
-			Authorization: "",
-			ContentType:   "application/json",
-			LogBody:       false,
-			Logger:        model.DiscardLogger,
-			MaxBodySize:   DefaultMaxBodySize,
-			Method:        http.MethodPost,
-			RequestBody:   []byte(`{"Name":"sbs","Age":99}`),
-			Timeout:       DefaultCallTimeout,
-			URLPath:       "/robots.txt",
-			URLQuery:      nil,
-		}
-		got, err := NewPOSTJSONWithJSONResponseDescriptor(model.DiscardLogger, "/robots.txt", request)
-		if err != nil {
-			log.Fatal(err)
-		}
-		if diff := cmp.Diff(expected, got); diff != "" {
-			t.Fatal(diff)
-		}
-	})
-}
-
-func TestMustNewPOSTJSONWithJSONResponseDescriptor(t *testing.T) {
-	type request struct {
-		Name string
-		Age  int64
-	}
-
-	t.Run("with failure", func(t *testing.T) {
-		var panicked bool
-		func() {
-			defer func() {
-				if r := recover(); r != nil {
-					panicked = true
-				}
-			}()
-			request := make(chan int64)
-			_ = MustNewPOSTJSONWithJSONResponseDescriptor(model.DiscardLogger, "/robots.txt", request)
-		}()
-		if !panicked {
-			t.Fatal("did not panic")
-		}
-	})
-
-	t.Run("with success", func(t *testing.T) {
-		request := request{
-			Name: "sbs",
-			Age:  99,
-		}
-		expected := &Descriptor{
-			Accept:        "application/json",
-			Authorization: "",
-			ContentType:   "application/json",
-			LogBody:       false,
-			Logger:        model.DiscardLogger,
-			MaxBodySize:   DefaultMaxBodySize,
-			Method:        http.MethodPost,
-			RequestBody:   []byte(`{"Name":"sbs","Age":99}`),
-			Timeout:       DefaultCallTimeout,
-			URLPath:       "/robots.txt",
-			URLQuery:      nil,
-		}
-		got := MustNewPOSTJSONWithJSONResponseDescriptor(model.DiscardLogger, "/robots.txt", request)
-		if diff := cmp.Diff(expected, got); diff != "" {
-			t.Fatal(diff)
-		}
-	})
-}
-
-func TestNewGetResourceDescriptor(t *testing.T) {
-	expected := &Descriptor{
-		Accept:        "",
-		Authorization: "",
-		ContentType:   "",
-		LogBody:       false,
-		Logger:        model.DiscardLogger,
-		MaxBodySize:   DefaultMaxBodySize,
-		Method:        http.MethodGet,
-		RequestBody:   nil,
-		Timeout:       DefaultCallTimeout,
-		URLPath:       "/robots.txt",
-		URLQuery:      url.Values{},
-	}
-	got := NewGETResourceDescriptor(model.DiscardLogger, "/robots.txt")
-	if diff := cmp.Diff(expected, got); diff != "" {
-		t.Fatal(diff)
-	}
-}

internal/httpapi/doc.go

@@ -1,15 +0,0 @@
-// Package httpapi contains code for calling HTTP APIs.
-//
-// We model HTTP APIs as follows:
-//
-// 1. |Endpoint| is an API endpoint (e.g., https://api.ooni.io);
-//
-// 2. |Descriptor| describes the specific API you want to use (e.g.,
-// GET /api/v1/test-list/urls with JSON response body).
-//
-// Generally, you use |Call| to call the API identified by a |Descriptor|
-// on the specified |Endpoint|. However, there are cases where you
-// need more complex calling patterns. For example, with |SequenceCaller|
-// you can invoke the same API |Descriptor| with multiple equivalent
-// API |Endpoint|s until one of them succeeds or all fail.
-package httpapi

internal/httpapi/endpoint.go

@@ -1,76 +0,0 @@
-package httpapi
-
-//
-// HTTP API Endpoint (e.g., https://api.ooni.io)
-//
-
-import "github.com/ooni/probe-cli/v3/internal/model"
-
-// Endpoint models an HTTP endpoint on which you can call
-// several HTTP APIs (e.g., https://api.ooni.io) using a
-// given HTTP client potentially using a circumvention tunnel
-// mechanism such as psiphon or torsf.
-//
-// The zero value of this struct is invalid. Please, fill all the
-// fields marked as MANDATORY for correct initialization.
-type Endpoint struct {
-	// BaseURL is the MANDATORY endpoint base URL. We will honour the
-	// path of this URL and prepend it to the actual path specified inside
-	// a |Descriptor.URLPath|. However, we will always discard any query
-	// that may have been set inside the BaseURL. The only query string
-	// will be composed from the |Descriptor.URLQuery| values.
-	//
-	// For example, https://api.ooni.io.
-	BaseURL string
-
-	// HTTPClient is the MANDATORY HTTP client to use.
-	//
-	// For example, http.DefaultClient. You can introduce circumvention
-	// here by using an HTTPClient bound to a specific tunnel.
-	HTTPClient model.HTTPClient
-
-	// Host is the OPTIONAL host header to use.
-	//
-	// If this field is empty we use the BaseURL's hostname. A specific
-	// host header may be needed when using cloudfronting.
-	Host string
-
-	// User-Agent is the OPTIONAL user-agent to use. If empty,
-	// we'll use the stdlib's default user-agent string.
-	UserAgent string
-}
-
-// NewEndpointList constructs a list of API endpoints from |services|
-// returned by the OONI backend (or known in advance).
-//
-// Arguments:
-//
-// - httpClient is the HTTP client to use for accessing the endpoints;
-//
-// - userAgent is the user agent you would like to use;
-//
-// - service is the list of services gathered from the backend.
-func NewEndpointList(httpClient model.HTTPClient,
-	userAgent string, services ...model.OOAPIService) (out []*Endpoint) {
-	for _, svc := range services {
-		switch svc.Type {
-		case "https":
-			out = append(out, &Endpoint{
-				BaseURL:    svc.Address,
-				HTTPClient: httpClient,
-				Host:       "",
-				UserAgent:  userAgent,
-			})
-		case "cloudfront":
-			out = append(out, &Endpoint{
-				BaseURL:    svc.Address,
-				HTTPClient: httpClient,
-				Host:       svc.Front,
-				UserAgent:  userAgent,
-			})
-		default:
-			// nothing!
-		}
-	}
-	return
-}

internal/httpapi/endpoint_test.go

@@ -1,69 +0,0 @@
-package httpapi
-
-import (
-	"testing"
-
-	"github.com/google/go-cmp/cmp"
-	"github.com/ooni/probe-cli/v3/internal/model"
-	"github.com/ooni/probe-cli/v3/internal/model/mocks"
-)
-
-func TestNewEndpointList(t *testing.T) {
-	type args struct {
-		httpClient model.HTTPClient
-		userAgent  string
-		services   []model.OOAPIService
-	}
-	defaultHTTPClient := &mocks.HTTPClient{}
-	tests := []struct {
-		name    string
-		args    args
-		wantOut []*Endpoint
-	}{{
-		name: "with no services",
-		args: args{
-			httpClient: defaultHTTPClient,
-			userAgent:  model.HTTPHeaderUserAgent,
-			services:   nil,
-		},
-		wantOut: nil,
-	}, {
-		name: "common cases",
-		args: args{
-			httpClient: defaultHTTPClient,
-			userAgent:  model.HTTPHeaderUserAgent,
-			services: []model.OOAPIService{{
-				Address: "https://www.example.com/",
-				Type:    "https",
-				Front:   "",
-			}, {
-				Address: "https://www.example.org/",
-				Type:    "cloudfront",
-				Front:   "example.org.it",
-			}, {
-				Address: "https://nonexistent.onion/",
-				Type:    "onion",
-				Front:   "",
-			}},
-		},
-		wantOut: []*Endpoint{{
-			BaseURL:    "https://www.example.com/",
-			HTTPClient: defaultHTTPClient,
-			Host:       "",
-			UserAgent:  model.HTTPHeaderUserAgent,
-		}, {
-			BaseURL:    "https://www.example.org/",
-			HTTPClient: defaultHTTPClient,
-			Host:       "example.org.it",
-			UserAgent:  model.HTTPHeaderUserAgent,
-		}},
-	}}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			gotOut := NewEndpointList(tt.args.httpClient, tt.args.userAgent, tt.args.services...)
-			if diff := cmp.Diff(tt.wantOut, gotOut); diff != "" {
-				t.Fatal(diff)
-			}
-		})
-	}
-}

internal/httpapi/sequence.go

@@ -1,92 +0,0 @@
-package httpapi
-
-//
-// Sequentially call available API endpoints until one succeed
-// or all of them fail. A future implementation of this code may
-// (probably should?) take into account knowledge of what is
-// working and what is not working to optimize the order with
-// which to try different alternatives.
-//
-
-import (
-	"context"
-	"errors"
-
-	"github.com/ooni/probe-cli/v3/internal/multierror"
-)
-
-// SequenceCaller calls the API specified by |Descriptor| once for each of
-// the available |Endpoints| until one of them succeeds.
-//
-// CAVEAT: this code will ONLY retry API calls with subsequent endpoints when
-// the error originates in the HTTP round trip or while reading the body.
-type SequenceCaller struct {
-	// Descriptor is the API |Descriptor|.
-	Descriptor *Descriptor
-
-	// Endpoints is the list of |Endpoint| to use.
-	Endpoints []*Endpoint
-}
-
-// NewSequenceCaller is a factory for creating a |SequenceCaller|.
-func NewSequenceCaller(desc *Descriptor, endpoints ...*Endpoint) *SequenceCaller {
-	return &SequenceCaller{
-		Descriptor: desc,
-		Endpoints:  endpoints,
-	}
-}
-
-// ErrAllEndpointsFailed indicates that all endpoints failed.
-var ErrAllEndpointsFailed = errors.New("httpapi: all endpoints failed")
-
-// shouldRetry returns true when we should try with another endpoint given the
-// value of |err| which could (obviously) be nil in case of success.
-func (sc *SequenceCaller) shouldRetry(err error) bool {
-	var kind *errMaybeCensorship
-	belongs := errors.As(err, &kind)
-	return belongs
-}
-
-// Call calls |Call| for each |Endpoint| and |Descriptor| until one endpoint succeeds. The
-// return value is the response body and the selected endpoint index or the error.
-//
-// CAVEAT: this code will ONLY retry API calls with subsequent endpoints when
-// the error originates in the HTTP round trip or while reading the body.
-func (sc *SequenceCaller) Call(ctx context.Context) ([]byte, int, error) {
-	var selected int
-	merr := multierror.New(ErrAllEndpointsFailed)
-	for _, epnt := range sc.Endpoints {
-		respBody, err := Call(ctx, sc.Descriptor, epnt)
-		if sc.shouldRetry(err) {
-			merr.Add(err)
-			selected++
-			continue
-		}
-		// Note: some errors will lead us to return
-		// early as documented for this method
-		return respBody, selected, err
-	}
-	return nil, -1, merr
-}
-
-// CallWithJSONResponse is like |SequenceCaller.Call| except that it invokes the
-// underlying |CallWithJSONResponse| rather than invoking |Call|.
-//
-// CAVEAT: this code will ONLY retry API calls with subsequent endpoints when
-// the error originates in the HTTP round trip or while reading the body.
-func (sc *SequenceCaller) CallWithJSONResponse(ctx context.Context, response any) (int, error) {
-	var selected int
-	merr := multierror.New(ErrAllEndpointsFailed)
-	for _, epnt := range sc.Endpoints {
-		err := CallWithJSONResponse(ctx, sc.Descriptor, epnt, response)
-		if sc.shouldRetry(err) {
-			merr.Add(err)
-			selected++
-			continue
-		}
-		// Note: some errors will lead us to return
-		// early as documented for this method
-		return selected, err
-	}
-	return -1, merr
-}

internal/httpapi/sequence_test.go

@@ -1,358 +0,0 @@
-package httpapi
-
-import (
-	"context"
-	"errors"
-	"io"
-	"net/http"
-	"strings"
-	"testing"
-
-	"github.com/google/go-cmp/cmp"
-	"github.com/ooni/probe-cli/v3/internal/model"
-	"github.com/ooni/probe-cli/v3/internal/model/mocks"
-)
-
-func TestSequenceCaller(t *testing.T) {
-	t.Run("Call", func(t *testing.T) {
-		t.Run("first success", func(t *testing.T) {
-			sc := NewSequenceCaller(
-				&Descriptor{
-					Logger:  model.DiscardLogger,
-					Method:  http.MethodGet,
-					URLPath: "/",
-				},
-				&Endpoint{
-					BaseURL: "https://a.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							resp := &http.Response{
-								StatusCode: 200,
-								Body:       io.NopCloser(strings.NewReader("deadbeef")),
-							}
-							return resp, nil
-						},
-					},
-				},
-				&Endpoint{
-					BaseURL: "https://b.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF
-						},
-					},
-				},
-			)
-			data, idx, err := sc.Call(context.Background())
-			if err != nil {
-				t.Fatal(err)
-			}
-			if idx != 0 {
-				t.Fatal("invalid idx")
-			}
-			if diff := cmp.Diff([]byte("deadbeef"), data); diff != "" {
-				t.Fatal(diff)
-			}
-		})
-
-		t.Run("first HTTP failure and we immediately stop", func(t *testing.T) {
-			sc := NewSequenceCaller(
-				&Descriptor{
-					Logger:  model.DiscardLogger,
-					Method:  http.MethodGet,
-					URLPath: "/",
-				},
-				&Endpoint{
-					BaseURL: "https://a.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							resp := &http.Response{
-								StatusCode: 403, // should cause us to return early
-								Body:       io.NopCloser(strings.NewReader("deadbeef")),
-							}
-							return resp, nil
-						},
-					},
-				},
-				&Endpoint{
-					BaseURL: "https://b.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF
-						},
-					},
-				},
-			)
-			data, idx, err := sc.Call(context.Background())
-			var failure *ErrHTTPRequestFailed
-			if !errors.As(err, &failure) || failure.StatusCode != 403 {
-				t.Fatal("unexpected err", err)
-			}
-			if idx != 0 {
-				t.Fatal("invalid idx")
-			}
-			if len(data) > 0 {
-				t.Fatal("expected to see no response body")
-			}
-		})
-
-		t.Run("first network failure, second success", func(t *testing.T) {
-			sc := NewSequenceCaller(
-				&Descriptor{
-					Logger:  model.DiscardLogger,
-					Method:  http.MethodGet,
-					URLPath: "/",
-				},
-				&Endpoint{
-					BaseURL: "https://a.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF // should cause us to cycle to the second entry
-						},
-					},
-				},
-				&Endpoint{
-					BaseURL: "https://b.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							resp := &http.Response{
-								StatusCode: 200,
-								Body:       io.NopCloser(strings.NewReader("abad1dea")),
-							}
-							return resp, nil
-						},
-					},
-				},
-			)
-			data, idx, err := sc.Call(context.Background())
-			if err != nil {
-				t.Fatal(err)
-			}
-			if idx != 1 {
-				t.Fatal("invalid idx")
-			}
-			if diff := cmp.Diff([]byte("abad1dea"), data); diff != "" {
-				t.Fatal(diff)
-			}
-		})
-
-		t.Run("all network failure", func(t *testing.T) {
-			sc := NewSequenceCaller(
-				&Descriptor{
-					Logger:  model.DiscardLogger,
-					Method:  http.MethodGet,
-					URLPath: "/",
-				},
-				&Endpoint{
-					BaseURL: "https://a.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF // should cause us to cycle to the next entry
-						},
-					},
-				},
-				&Endpoint{
-					BaseURL: "https://b.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF // should cause us to cycle to the next entry
-						},
-					},
-				},
-			)
-			data, idx, err := sc.Call(context.Background())
-			if !errors.Is(err, ErrAllEndpointsFailed) {
-				t.Fatal("unexpected err", err)
-			}
-			if idx != -1 {
-				t.Fatal("invalid idx")
-			}
-			if len(data) > 0 {
-				t.Fatal("expected zero-length data")
-			}
-		})
-	})
-
-	t.Run("CallWithJSONResponse", func(t *testing.T) {
-		type response struct {
-			Name string
-			Age  int64
-		}
-
-		t.Run("first success", func(t *testing.T) {
-			sc := NewSequenceCaller(
-				&Descriptor{
-					Logger:  model.DiscardLogger,
-					Method:  http.MethodGet,
-					URLPath: "/",
-				},
-				&Endpoint{
-					BaseURL: "https://a.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							resp := &http.Response{
-								StatusCode: 200,
-								Body:       io.NopCloser(strings.NewReader(`{"Name":"sbs","Age":99}`)),
-							}
-							return resp, nil
-						},
-					},
-				},
-				&Endpoint{
-					BaseURL: "https://b.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							resp := &http.Response{
-								StatusCode: 200,
-								Body:       io.NopCloser(strings.NewReader(`{}`)), // different
-							}
-							return resp, nil
-						},
-					},
-				},
-			)
-			expect := response{
-				Name: "sbs",
-				Age:  99,
-			}
-			var got response
-			idx, err := sc.CallWithJSONResponse(context.Background(), &got)
-			if err != nil {
-				t.Fatal(err)
-			}
-			if idx != 0 {
-				t.Fatal("invalid idx")
-			}
-			if diff := cmp.Diff(expect, got); diff != "" {
-				t.Fatal(diff)
-			}
-		})
-
-		t.Run("first HTTP failure and we immediately stop", func(t *testing.T) {
-			sc := NewSequenceCaller(
-				&Descriptor{
-					Logger:  model.DiscardLogger,
-					Method:  http.MethodGet,
-					URLPath: "/",
-				},
-				&Endpoint{
-					BaseURL: "https://a.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							resp := &http.Response{
-								StatusCode: 403, // should be enough to cause us fail immediately
-								Body:       io.NopCloser(strings.NewReader(`{"Age": 155, "Name": "sbs"}`)),
-							}
-							return resp, nil
-						},
-					},
-				},
-				&Endpoint{
-					BaseURL: "https://b.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF
-						},
-					},
-				},
-			)
-			// even though there is a JSON body we don't care about reading it
-			// and so we expect to see in output the zero-value struct
-			expect := response{
-				Name: "",
-				Age:  0,
-			}
-			var got response
-			idx, err := sc.CallWithJSONResponse(context.Background(), &got)
-			var failure *ErrHTTPRequestFailed
-			if !errors.As(err, &failure) || failure.StatusCode != 403 {
-				t.Fatal("unexpected err", err)
-			}
-			if idx != 0 {
-				t.Fatal("invalid idx")
-			}
-			if diff := cmp.Diff(expect, got); diff != "" {
-				t.Fatal(diff)
-			}
-		})
-
-		t.Run("first network failure, second success", func(t *testing.T) {
-			sc := NewSequenceCaller(
-				&Descriptor{
-					Logger:  model.DiscardLogger,
-					Method:  http.MethodGet,
-					URLPath: "/",
-				},
-				&Endpoint{
-					BaseURL: "https://a.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF // should cause us to try the next entry
-						},
-					},
-				},
-				&Endpoint{
-					BaseURL: "https://b.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							resp := &http.Response{
-								StatusCode: 200,
-								Body:       io.NopCloser(strings.NewReader(`{"Age":155}`)),
-							}
-							return resp, nil
-						},
-					},
-				},
-			)
-			expect := response{
-				Name: "",
-				Age:  155,
-			}
-			var got response
-			idx, err := sc.CallWithJSONResponse(context.Background(), &got)
-			if err != nil {
-				t.Fatal(err)
-			}
-			if idx != 1 {
-				t.Fatal("invalid idx")
-			}
-			if diff := cmp.Diff(expect, got); diff != "" {
-				t.Fatal(diff)
-			}
-		})
-
-		t.Run("all network failure", func(t *testing.T) {
-			sc := NewSequenceCaller(
-				&Descriptor{
-					Logger:  model.DiscardLogger,
-					Method:  http.MethodGet,
-					URLPath: "/",
-				},
-				&Endpoint{
-					BaseURL: "https://a.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF // should cause us to try the next entry
-						},
-					},
-				},
-				&Endpoint{
-					BaseURL: "https://b.example.com/",
-					HTTPClient: &mocks.HTTPClient{
-						MockDo: func(req *http.Request) (*http.Response, error) {
-							return nil, io.EOF // should cause us to try the next entry
-						},
-					},
-				},
-			)
-			var got response
-			idx, err := sc.CallWithJSONResponse(context.Background(), &got)
-			if !errors.Is(err, ErrAllEndpointsFailed) {
-				t.Fatal("unexpected err", err)
-			}
-			if idx != -1 {
-				t.Fatal("invalid idx")
-			}
-		})
-	})
-}

internal/httpx/httpx.go

@@ -1,8 +1,4 @@
 // Package httpx contains http extensions.
-//
-// Deprecated: new code should use httpapi instead. While this package and httpapi
-// are basically using the same implementation, the API exposed by httpapi allows
-// us to try the same request with multiple HTTP endpoints.
 package httpx
 
 import (

internal/model/experiment.go

@@ -117,19 +117,6 @@ func (d PrinterCallbacks) OnProgress(percentage float64, message string) {
 	d.Logger.Infof("[%5.1f%%] %s", percentage*100, message)
 }
 
-// ExperimentArgs contains the arguments passed to an experiment.
-type ExperimentArgs struct {
-	// Callbacks contains MANDATORY experiment callbacks.
-	Callbacks ExperimentCallbacks
-
-	// Measurement is the MANDATORY measurement in which the experiment
-	// must write the results of the measurement.
-	Measurement *Measurement
-
-	// Session is the MANDATORY session the experiment can use.
-	Session ExperimentSession
-}
-
 // ExperimentMeasurer is the interface that allows to run a
 // measurement for a specific experiment.
 type ExperimentMeasurer interface {
@@ -146,7 +133,10 @@ type ExperimentMeasurer interface {
 	// set the relevant OONI error inside of the measurement and
 	// return nil. This is important because the caller WILL NOT submit
 	// the measurement if this method returns an error.
-	Run(ctx context.Context, args *ExperimentArgs) error
+	Run(
+		ctx context.Context, sess ExperimentSession,
+		measurement *Measurement, callbacks ExperimentCallbacks,
+	) error
 
 	// GetSummaryKeys returns summary keys expected by ooni/probe-cli.
 	GetSummaryKeys(*Measurement) (interface{}, error)

internal/registry/smtp.go

@@ -0,0 +1,22 @@
+package registry
+
+//
+// Registers the `dnsping' experiment.
+//
+
+import (
+	"github.com/ooni/probe-cli/v3/internal/engine/experiment/smtp"
+	"github.com/ooni/probe-cli/v3/internal/model"
+)
+
+func init() {
+	AllExperiments["smtp"] = &Factory{
+		build: func(config interface{}) model.ExperimentMeasurer {
+			return smtp.NewExperimentMeasurer(
+				*config.(*smtp.Config),
+			)
+		},
+		config:      &smtp.Config{},
+		inputPolicy: model.InputOrStaticDefault,
+	}
+}

internal/tutorial/experiment/torsf/chapter01/README.md

@@ -211,12 +211,7 @@ need any fancy context and we pass a `context.Background` to `Run`.
 
 ```Go
 	ctx := context.Background()
-	args := &model.ExperimentArgs{
+	if err = m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err = m.Run(ctx, args); err != nil {
 		log.WithError(err).Fatal("torsf experiment failed")
 	}
 ```

internal/tutorial/experiment/torsf/chapter01/main.go

@@ -212,12 +212,7 @@ func main() {
 	//
 	// ```Go
 	ctx := context.Background()
-	args := &model.ExperimentArgs{
+	if err = m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err = m.Run(ctx, args); err != nil {
 		log.WithError(err).Fatal("torsf experiment failed")
 	}
 	// ```

internal/tutorial/experiment/torsf/chapter02/README.md

@@ -117,10 +117,10 @@ chapters, finally, we will modify this function until it is a
 minimal implementation of the `torsf` experiment.
 
 ```Go
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	_ = args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 ```
 As you can see, this is just a stub implementation that sleeps
 for one second and prints a logging message.

internal/tutorial/experiment/torsf/chapter02/main.go

@@ -54,12 +54,7 @@ func main() {
 		MockableLogger:  log.Log,
 		MockableTempDir: tempdir,
 	}
-	args := &model.ExperimentArgs{
+	if err = m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err = m.Run(ctx, args); err != nil {
 		log.WithError(err).Fatal("torsf experiment failed")
 	}
 	data, err := json.Marshal(measurement)

internal/tutorial/experiment/torsf/chapter02/torsf.go

@@ -93,10 +93,10 @@ func (m *Measurer) ExperimentVersion() string {
 // minimal implementation of the `torsf` experiment.
 //
 // ```Go
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	_ = args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	_ = args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 	// ```
 	// As you can see, this is just a stub implementation that sleeps
 	// for one second and prints a logging message.

internal/tutorial/experiment/torsf/chapter03/README.md

@@ -32,10 +32,10 @@ print periodic updates via the `callbacks`. We will defer the
 real work to a private function called `run`.
 
 ```Go
-func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+func (m *Measurer) Run(
-	callbacks := args.Callbacks
+	ctx context.Context, sess model.ExperimentSession,
-	measurement := args.Measurement
+	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-	sess := args.Session
+) error {
 ```
 
 Let's create an instance of `TestKeys` and let's modify

internal/tutorial/experiment/torsf/chapter03/main.go

@@ -28,12 +28,7 @@ func main() {
 		MockableLogger:  log.Log,
 		MockableTempDir: tempdir,
 	}
-	args := &model.ExperimentArgs{
+	if err = m.Run(ctx, sess, measurement, callbacks); err != nil {
-		Callbacks:   callbacks,
-		Measurement: measurement,
-		Session:     sess,
-	}
-	if err = m.Run(ctx, args); err != nil {
 		log.WithError(err).Fatal("torsf experiment failed")
 	}
 	data, err := json.Marshal(measurement)