This is the extension of https://github.com/ooni/probe-cli/pull/431, and my final deliverable for GSoC 2021.
The diff introduces:
1) The new `testhelper` which supports testing multiple IP endpoints per domain and introduces HTTP/3 control measurements. The specification of the `testhelper` can be found at https://github.com/ooni/spec/pull/219. The `testhelper` algorithm consists of three main steps:
* `InitialChecks` verifies that the input URL can be parsed, has an expected scheme, and contains a valid domain name.
* `Explore` enumerates all the URLs that it discovers by redirection from the original URL, or by detecting h3 support at the target host.
* `Generate` performs a step-by-step measurement of each discovered URL.
2) A prototype of the corresponding new experiment `websteps` which uses the control measurement of the `testhelper` to know which URLs to measure, and what to expect. The prototype does not yet have:
* unit and integration tests,
* an analysis tool to compare the control and the probe measurement.
This PR is my final deliverable as it is the outcome of the trials, considerations and efforts of my GSoC weeks at OONI.
It fully integrates HTTP/3 (QUIC) support which has been only used in the `urlgetter` experiment until now.
Related issues: https://github.com/ooni/probe/issues/1729 and https://github.com/ooni/probe/issues/1733.
The utility of SafeErrWrapperBuilder is low. Let us instead change the
code to always create ErrWrapper when we're in this package.
While there, also note some TODO-next items.
Part of https://github.com/ooni/probe/issues/1505.
* refactor(errorsx): start hiding private details and moving around stuff
Part of https://github.com/ooni/probe/issues/1505
* fix: remove now-addressed todo comments
* refactor: cleaner way of passing a UDPConn around
Also part of https://github.com/ooni/probe/issues/1505
* Update internal/engine/netx/quicdialer/connectionstate.go
I needed to add some tests as integration tests due to circular
imports, but this is ~fine because we quite likely want many
integration tests in the errorsx package anyway.
Part of https://github.com/ooni/probe/issues/1505.
With this factory, we want to construct ourselves the TLS dialer
so that we can use a dialer wrapper that always sets timeouts when
reading, addressing https://github.com/ooni/probe/issues/1609.
As a result, we cannot immediately replace the i/e/netx factory
for creating a new HTTP transport, since the functions signatures
are not directly compatible.
Refactoring is part of https://github.com/ooni/probe/issues/1505.
This diff is part of https://github.com/ooni/probe/issues/1505.
You will notice that I have not adapted all the (great) tests we had
previously. They should live at another layer, and namely the one that
deals with performing measurements.
When I'm refactoring such a layer I'll ensure those tests that I have
not adapted here are reintroduced into the tree.
Auto-configure every relevant TLS field as close as possible to
where it's actually used.
As a side effect, add support for mocking the creation of a TLS
connection, which should possibly be useful for uTLS?
Work that is part of https://github.com/ooni/probe/issues/1505
The BogonResolver relied on its wrapper resolver to pass along the
list of addresses _and_ the error. But the idiomatic thing to do is
often to return `nil` when there is an error.
I broke this very fragile assumption in https://github.com/ooni/probe-cli/pull/399.
I could of course fix it, but this assumption is clearly wrong
and we should not allow such fragile code in the tree.
We are not using BogonIsError much in the tree. The only place in
which we're using it for measuring seems to be dnscheck.
It may be that this surprising behavior was what caused the issue at
https://github.com/ooni/probe/issues/1510 in the first place.
Regardless, let's remove fragile code and adjust the test that was
failing. Also that test is quick so it can run in `-short` mode.
Spotted while working on https://github.com/ooni/probe/issues/1505.
* refactor(netxlite): make sure we always use netmocks
While there, improve logging and make sure we test 100% of the
package with unit tests only. (We don't need to have integration
testing in this package because it's fairly simple/obvious.)
Part of https://github.com/ooni/probe/issues/1505
* further improve logs
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.
We are not using them anymore. The only nettest still using the
legacy netx implementation is tor, for which setting these fields
is useless, because it performs each measurement into a separate
goroutine. Hence, let us start removing this part of the legacy
netx codebase, which is hampering progress in other areas.
Occurred to me while doing testing for the recent changes in
error mapping (https://github.com/ooni/probe/issues/1505).
* refactor: move scrubbingLogger to the scrubber pkg
We need it exported so we can use it in the new implementation.
Part of https://github.com/ooni/probe/issues/1687
* fix test
* refactor: move bytecounting conn in bytecounter pkg
This enables other pieces of code to request bytecounting without
depending on netx or on the perverse using-the-context-to-configure-
byte-counting mechanism.
Also occurred when working on https://github.com/ooni/probe/issues/1687
* fix: add missing docs
The current implementation assumes the user has already installed tor
on the current system. If tor is not present, the experiment fails.
This is meant to be the first version of this experiment.
We are going to add more functionality in subsequent revisions of
this experiment, once we've collected more feedback.
Reference issue: https://github.com/ooni/probe/issues/1565.
Here's the spec PR: https://github.com/ooni/spec/pull/218.
Here's the issue tracking future work: https://github.com/ooni/probe/issues/1686
Simone Basso
kelmenhorst
kelmenhorst