ooni-probe-cli/internal/experiment/webconnectivity/analysishttpcore.go
Simone Basso 5e76c6ec92
refactor(webconnectivity@v0.5): improve logging clarity (#964)
We're bumping the experiment's version number because we changed the name of the field used to contain late/duplicate DNS responses. We have also changed the algorithm to determine `#dnsDiff`. However, the change should only impact how we log this information. Overall, here the idea is to provide users with a reasonably clear explanation of how the probe maps observations to blocking and accessible using expected/unexpected as the conceptual framework.

Part of https://github.com/ooni/probe/issues/2237
2022-09-15 07:03:53 +02:00

70 lines
1.9 KiB
Go

package webconnectivity
//
// HTTP core analysis
//
import (
"github.com/ooni/probe-cli/v3/internal/model"
"github.com/ooni/probe-cli/v3/internal/netxlite"
)
// analysisHTTPToplevel is the toplevel analysis function for HTTP results.
//
// This function's job is to determine whether there were unexpected TLS
// handshake results (compared to what the TH observed), or unexpected
// failures during HTTP round trips (using the TH as benchmark), or whether
// the obtained body differs from the one obtained by the TH.
//
// This results in possibly setting these XBlockingFlags:
//
// - analysisFlagHTTPBlocking
//
// - analysisFlagHTTPDiff
//
// In websteps fashion, we don't stop at the first failure, rather we
// process all the available data and evaluate all possible errors.
func (tk *TestKeys) analysisHTTPToplevel(logger model.Logger) {
// if we don't have any request to check, there's not much more we
// can actually do here, so let's just return.
if len(tk.Requests) <= 0 {
return
}
finalRequest := tk.Requests[0]
tk.HTTPExperimentFailure = finalRequest.Failure
// don't perform any futher analysis without TH data
if tk.Control == nil || tk.ControlRequest == nil {
return
}
ctrl := tk.Control.HTTPRequest
// don't perform any analysis if the TH's HTTP measurement failed because
// performing more precise mapping is a job for the pipeline.
if ctrl.Failure != nil {
return
}
// flag cases of known HTTP failures
if failure := finalRequest.Failure; failure != nil {
switch *failure {
case netxlite.FailureConnectionReset,
netxlite.FailureGenericTimeoutError,
netxlite.FailureEOFError:
tk.BlockingFlags |= analysisFlagHTTPBlocking
logger.Warnf(
"HTTP: unexpected failure %s for %s (see #%d)",
*failure,
finalRequest.Address,
finalRequest.TransactionID,
)
default:
// leave this case for ooni/pipeline
}
return
}
// fallback to the HTTP diff algo.
tk.analysisHTTPDiff(logger, finalRequest, &ctrl)
}