ooni-probe-cli/internal/measurex/dnsx.go
Simone Basso 8a0c062844
feat: clearly indicate which resolver we're using (#885)
See what we documented at https://github.com/ooni/spec/pull/257

Reference issue: https://github.com/ooni/probe/issues/2238

See also the related ooni/spec PR: https://github.com/ooni/spec/pull/257

See also https://github.com/ooni/probe/issues/2237

While there, bump webconnectivity@v0.5 version because this change
has an impact onto the generated data format.

The drop in coverage is unavoidable because we've written some
tests for `measurex` to ensure we deal with DNS resolvers and transport
names correctly depending on the splitting policy we use.

(However, `measurex` is only used for the `tor` experiment and, per
the step-by-step design document, new experiments should use
`measurexlite` instead, so this is hopefully fine(TM).)

While there, fix a broken integration test that does not run in `-short` mode.
2022-08-27 15:47:48 +02:00

68 lines
1.7 KiB
Go

package measurex
//
// DNSX (DNS eXtensions)
//
// We wrap dnsx.RoundTripper to store events into a WritableDB.
//
import (
"context"
"time"
"github.com/ooni/probe-cli/v3/internal/model"
"github.com/ooni/probe-cli/v3/internal/tracex"
)
// WrapDNSXRoundTripper creates a new DNSXRoundTripper that
// saves events into the given WritableDB.
func (mx *Measurer) WrapDNSXRoundTripper(db WritableDB, rtx model.DNSTransport) model.DNSTransport {
return &dnsxRoundTripperDB{db: db, DNSTransport: rtx, begin: mx.Begin}
}
type dnsxRoundTripperDB struct {
model.DNSTransport
begin time.Time
db WritableDB
}
// DNSRoundTripEvent contains the result of a DNS round trip.
type DNSRoundTripEvent struct {
Network string
Address string
Query []byte
Started float64
Finished float64
Failure *string
Reply []byte
}
func (txp *dnsxRoundTripperDB) RoundTrip(
ctx context.Context, query model.DNSQuery) (model.DNSResponse, error) {
started := time.Since(txp.begin).Seconds()
response, err := txp.DNSTransport.RoundTrip(ctx, query)
finished := time.Since(txp.begin).Seconds()
txp.db.InsertIntoDNSRoundTrip(&DNSRoundTripEvent{
Network: tracex.ResolverNetworkAdaptNames(txp.DNSTransport.Network()),
Address: txp.DNSTransport.Address(),
Query: txp.maybeQueryBytes(query),
Started: started,
Finished: finished,
Failure: NewFailure(err),
Reply: txp.maybeResponseBytes(response),
})
return response, err
}
func (txp *dnsxRoundTripperDB) maybeQueryBytes(query model.DNSQuery) []byte {
data, _ := query.Bytes()
return data
}
func (txp *dnsxRoundTripperDB) maybeResponseBytes(response model.DNSResponse) []byte {
if response == nil {
return nil
}
return response.Bytes()
}