ooni-probe-cli/internal/netxlite/dialer.go
Simone Basso 2e0118d1a6
refactor(netxlite): hide details without breaking the rest of the tree (#454)
## Description

This PR continues the refactoring of `netx` under the following principles:

1. do not break the rest of the tree and do not engage in extensive tree-wide refactoring yet
2. move under `netxlite` clearly related subpackages (e.g., `iox`, `netxmocks`)
3. move into `internal/netxlite/internal` stuff that is clearly private of `netxlite`
4. hide implementation details in `netxlite` pending new factories
5. refactor `tls` code in `netxlite` to clearly separate `crypto/tls` code from `utls` code

After each commit, I run `go test -short -race ./...` locally. Each individual commit explains what it does. I will squash, but this operation will preserve the original commit titles, so this will give further insight on each step.

## Commits

* refactor: rename netxmocks -> netxlite/mocks

Part of https://github.com/ooni/probe/issues/1591

* refactor: rename quicx -> netxlite/quicx

See https://github.com/ooni/probe/issues/1591

* refactor: rename iox -> netxlite/iox

Regenerate sources and make sure the tests pass.

See https://github.com/ooni/probe/issues/1591.

* refactor(iox): move MockableReader to netxlite/mocks

See https://github.com/ooni/probe/issues/1591

* refactor(netxlite): generator is an implementation detail

See https://github.com/ooni/probe/issues/1591

* refactor(netxlite): separate tls and utls code

See https://github.com/ooni/probe/issues/1591

* refactor(netxlite): hide most types but keep old names as legacy

With this change we avoid breaking the rest of the tree, but we start
hiding some implementation details a bit. Factories will follow.

See https://github.com/ooni/probe/issues/1591
2021-09-05 14:49:38 +02:00

93 lines
2.5 KiB
Go

package netxlite
import (
"context"
"net"
"time"
)
// Dialer establishes network connections.
type Dialer interface {
// DialContext behaves like net.Dialer.DialContext.
DialContext(ctx context.Context, network, address string) (net.Conn, error)
}
// defaultDialer is the Dialer we use by default.
var defaultDialer = &net.Dialer{
Timeout: 15 * time.Second,
KeepAlive: 15 * time.Second,
}
var _ Dialer = defaultDialer
// dialerResolver is a dialer that uses the configured Resolver to resolver a
// domain name to IP addresses, and the configured Dialer to connect.
type dialerResolver struct {
// Dialer is the underlying Dialer.
Dialer Dialer
// Resolver is the underlying Resolver.
Resolver Resolver
}
var _ Dialer = &dialerResolver{}
// DialContext implements Dialer.DialContext.
func (d *dialerResolver) DialContext(ctx context.Context, network, address string) (net.Conn, error) {
onlyhost, onlyport, err := net.SplitHostPort(address)
if err != nil {
return nil, err
}
addrs, err := d.lookupHost(ctx, onlyhost)
if err != nil {
return nil, err
}
// TODO(bassosimone): here we should be using multierror rather
// than just calling ReduceErrors. We are not ready to do that
// yet, though. To do that, we need first to modify nettests so
// that we actually avoid dialing when measuring.
var errorslist []error
for _, addr := range addrs {
target := net.JoinHostPort(addr, onlyport)
conn, err := d.Dialer.DialContext(ctx, network, target)
if err == nil {
return conn, nil
}
errorslist = append(errorslist, err)
}
return nil, reduceErrors(errorslist)
}
// lookupHost performs a domain name resolution.
func (d *dialerResolver) lookupHost(ctx context.Context, hostname string) ([]string, error) {
if net.ParseIP(hostname) != nil {
return []string{hostname}, nil
}
return d.Resolver.LookupHost(ctx, hostname)
}
// dialerLogger is a Dialer with logging.
type dialerLogger struct {
// Dialer is the underlying dialer.
Dialer Dialer
// Logger is the underlying logger.
Logger Logger
}
var _ Dialer = &dialerLogger{}
// DialContext implements Dialer.DialContext
func (d *dialerLogger) DialContext(ctx context.Context, network, address string) (net.Conn, error) {
d.Logger.Debugf("dial %s/%s...", address, network)
start := time.Now()
conn, err := d.Dialer.DialContext(ctx, network, address)
elapsed := time.Since(start)
if err != nil {
d.Logger.Debugf("dial %s/%s... %s in %s", address, network, err, elapsed)
return nil, err
}
d.Logger.Debugf("dial %s/%s... ok in %s", address, network, elapsed)
return conn, nil
}