ooni-probe-cli/internal/engine/netx/dialer/dialer.go
Simone Basso 58adb68b2c
refactor: move tracex outside of engine/netx (#782)
* refactor: move tracex outside of engine/netx

Consistently with https://github.com/ooni/probe/issues/2121 and
https://github.com/ooni/probe/issues/2115, we can now move tracex
outside of engine/netx. The main reason why this makes sense now
is that the package is now changed significantly from the one
that we imported from ooni/probe-engine.

We have improved its implementation, which had not been touched
significantly for quite some time, and converted it to unit
testing. I will document tomorrow some extra work I'd like to
do with this package but likely could not do $soon.

* go fmt

* regen tutorials
2022-06-02 00:50:55 +02:00

67 lines
2.2 KiB
Go

// Package dialer allows you to create a net.Dialer-compatible
// DialContext-enabled dialer with error wrapping, optional logging,
// optional network-events saving, and optional proxying.
package dialer
import (
"net/url"
"github.com/ooni/probe-cli/v3/internal/bytecounter"
"github.com/ooni/probe-cli/v3/internal/model"
"github.com/ooni/probe-cli/v3/internal/netxlite"
"github.com/ooni/probe-cli/v3/internal/tracex"
)
// Config contains the settings for New.
type Config struct {
// ContextByteCounting optionally configures context-based
// byte counting. By default we don't do that.
//
// Use WithExperimentByteCounter and WithSessionByteCounter
// to assign byte counters to a context. The code will use
// corresponding, private functions to access the configured
// byte counters and will notify them about I/O events.
//
// Bug
//
// This implementation cannot properly account for the bytes that are sent by
// persistent connections, because they stick to the counters set when the
// connection was established. This typically means we miss the bytes sent and
// received when submitting a measurement. Such bytes are specifically not
// seen by the experiment specific byte counter.
//
// For this reason, this implementation may be heavily changed/removed.
ContextByteCounting bool
// DialSaver is the optional saver for dialing events. If not
// set, we will not save any dialing event.
DialSaver *tracex.Saver
// Logger is the optional logger. If not set, there
// will be no logging from the new dialer.
Logger model.DebugLogger
// ProxyURL is the optional proxy URL.
ProxyURL *url.URL
// ReadWriteSaver is like DialSaver but for I/O events.
ReadWriteSaver *tracex.Saver
}
// New creates a new Dialer from the specified config and resolver.
func New(config *Config, resolver model.Resolver) model.Dialer {
var logger model.DebugLogger = model.DiscardLogger
if config.Logger != nil {
logger = config.Logger
}
d := netxlite.NewDialerWithResolver(
logger, resolver, config.DialSaver.NewConnectObserver(),
config.ReadWriteSaver.NewReadWriteObserver(),
)
d = &netxlite.MaybeProxyDialer{ProxyURL: config.ProxyURL, Dialer: d}
if config.ContextByteCounting {
d = &bytecounter.ContextAwareDialer{Dialer: d}
}
return d
}