c/ooni-probe-cli
Watch
1
0
Fork
You've already forked ooni-probe-cli
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

refactor: start pivoting netx (#396)

Browse source 
What do I mean by pivoting? Netx is currently organized by row:

```
               | dialer | quicdialer | resolver | ...
 saving        |        |            |          | ...
 errorwrapping |        |            |          | ...
 logging       |        |            |          | ...
 mocking/sys   |        |            |          | ...
```

Every row needs to implement saving, errorwrapping, logging, mocking (or
adapting to the system or to some underlying library).

This causes cross package dependencies and, in turn, complexity. For
example, we need the `trace` package for supporting saving.

And `dialer`, `quickdialer`, et al. need to depend on such a package.

The same goes for errorwrapping.

This arrangement further complicates testing. For example, I am
currently working on https://github.com/ooni/probe/issues/1505 and
I realize it need to repeat integration tests in multiple places.

Let's say instead we pivot the above matrix as follows:

```
             | saving | errorwrapping | logging | ...
 dialer      |        |               |         | ...
 quicdialer  |        |               |         | ...
 logging     |        |               |         | ...
 mocking/sys |        |               |         | ...
 ...
```

In this way, now every row contains everything related to a specific
action to perform. We can now share code without relying on extra
support packages. What's more, we can write tests and, judding from
the way in which things are made, it seems we only need integration
testing in `errorwrapping` because it's where data quality matters
whereas, in all other cases, unit testing is fine.

I am going, therefore, to proceed with these changes and "pivot"
`netx`. Hopefully, it won't be too painful.
This commit is contained in:
Simone Basso 2021-06-23 15:53:12 +02:00 • committed by GitHub
commit 8a0beee808
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
27 changed files with 455 additions and 351 deletions
Download patch file Download diff file Expand all files Collapse all files

155
internal/engine/netx/dialer/dns_test.go
View file

@ -1,155 +0,0 @@
package dialer
import (
"context"
"errors"
"io"
"net"
"testing"
"github.com/ooni/probe-cli/v3/internal/engine/netx/errorx"
"github.com/ooni/probe-cli/v3/internal/engine/netx/mockablex"
)
func TestDNSDialerNoPort(t *testing.T) {
dialer := &dnsDialer{Dialer: new(net.Dialer), Resolver: new(net.Resolver)}
conn, err := dialer.DialContext(context.Background(), "tcp", "antani.ooni.nu")
if err == nil {
t.Fatal("expected an error here")
}
if conn != nil {
t.Fatal("expected a nil conn here")
}
}
func TestDNSDialerLookupHostAddress(t *testing.T) {
dialer := &dnsDialer{Dialer: new(net.Dialer), Resolver: MockableResolver{
Err: errors.New("mocked error"),
}}
addrs, err := dialer.lookupHost(context.Background(), "1.1.1.1")
if err != nil {
t.Fatal(err)
}
if len(addrs) != 1 || addrs[0] != "1.1.1.1" {
t.Fatal("not the result we expected")
}
}
func TestDNSDialerLookupHostFailure(t *testing.T) {
expected := errors.New("mocked error")
dialer := &dnsDialer{Dialer: new(net.Dialer), Resolver: MockableResolver{
Err: expected,
}}
conn, err := dialer.DialContext(context.Background(), "tcp", "dns.google.com:853")
if !errors.Is(err, expected) {
t.Fatal("not the error we expected")
}
if conn != nil {
t.Fatal("expected nil conn")
}
}
type MockableResolver struct {
Addresses []string
Err error
}
func (r MockableResolver) LookupHost(ctx context.Context, host string) ([]string, error) {
return r.Addresses, r.Err
}
func TestDNSDialerDialForSingleIPFails(t *testing.T) {
dialer := &dnsDialer{Dialer: mockablex.Dialer{
MockDialContext: func(ctx context.Context, network string, address string) (net.Conn, error) {
return nil, io.EOF
},
}, Resolver: new(net.Resolver)}
conn, err := dialer.DialContext(context.Background(), "tcp", "1.1.1.1:853")
if !errors.Is(err, io.EOF) {
t.Fatal("not the error we expected")
}
if conn != nil {
t.Fatal("expected nil conn")
}
}
func TestDNSDialerDialForManyIPFails(t *testing.T) {
dialer := &dnsDialer{
Dialer: mockablex.Dialer{
MockDialContext: func(ctx context.Context, network string, address string) (net.Conn, error) {
return nil, io.EOF
},
}, Resolver: MockableResolver{
Addresses: []string{"1.1.1.1", "8.8.8.8"},
}}
conn, err := dialer.DialContext(context.Background(), "tcp", "dot.dns:853")
if !errors.Is(err, io.EOF) {
t.Fatal("not the error we expected")
}
if conn != nil {
t.Fatal("expected nil conn")
}
}
func TestDNSDialerDialForManyIPSuccess(t *testing.T) {
dialer := &dnsDialer{Dialer: mockablex.Dialer{
MockDialContext: func(ctx context.Context, network string, address string) (net.Conn, error) {
return &mockablex.Conn{
MockClose: func() error {
return nil
},
}, nil
},
}, Resolver: MockableResolver{
Addresses: []string{"1.1.1.1", "8.8.8.8"},
}}
conn, err := dialer.DialContext(context.Background(), "tcp", "dot.dns:853")
if err != nil {
t.Fatal("expected nil error here")
}
if conn == nil {
t.Fatal("expected non-nil conn")
}
conn.Close()
}
func TestReduceErrors(t *testing.T) {
t.Run("no errors", func(t *testing.T) {
result := ReduceErrors(nil)
if result != nil {
t.Fatal("wrong result")
}
})
t.Run("single error", func(t *testing.T) {
err := errors.New("mocked error")
result := ReduceErrors([]error{err})
if result != err {
t.Fatal("wrong result")
}
})
t.Run("multiple errors", func(t *testing.T) {
err1 := errors.New("mocked error #1")
err2 := errors.New("mocked error #2")
result := ReduceErrors([]error{err1, err2})
if result.Error() != "mocked error #1" {
t.Fatal("wrong result")
}
})
t.Run("multiple errors with meaningful ones", func(t *testing.T) {
err1 := errors.New("mocked error #1")
err2 := &errorx.ErrWrapper{
Failure: "unknown_failure: antani",
}
err3 := &errorx.ErrWrapper{
Failure: errorx.FailureConnectionRefused,
}
err4 := errors.New("mocked error #3")
result := ReduceErrors([]error{err1, err2, err3, err4})
if result.Error() != errorx.FailureConnectionRefused {
t.Fatal("wrong result")
}
})
}