* 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
Rather than matching a string, match a type.
This is more robust considering future refactorings.
We're confident the names did not change in _this_ refactoring
because we're still testing the same strings in the tests.
Part of https://github.com/ooni/probe/issues/2121
This diff creates a new package under netx called tracex that
contains everything we need to perform measurements using events
tracing and postprocessing (which is the technique with which
we implement most network experiments).
The general idea here is to (1) create a unique package out of
all of these packages; (2) clean up the code a bit (improve tests,
docs, apply more recent code patterns); (3) move the resulting
code as a toplevel package inside of internal.
Once this is done, netx can be further refactored to avoid
subpackages and we can search for more code to salvage/refactor.
See https://github.com/ooni/probe/issues/2121
Since https://github.com/ooni/probe-cli/pull/527, if an experiment
returns an error, the corresponding measurement is not submitted since
the semantics of returning an error is that something fundamental
went wrong (e.g., we could not parse the input URL).
This diff ensures that all experiments only return and error when
something fundamental was wrong and return nil otherwise.
Reference issue: https://github.com/ooni/probe/issues/1808.
## Checklist
- [x] I have read the [contribution guidelines](https://github.com/ooni/probe-cli/blob/master/CONTRIBUTING.md)
- [x] reference issue for this pull request: https://github.com/ooni/probe/issues/1885
- [x] related ooni/spec pull request: N/A
Location of the issue tracker: https://github.com/ooni/probe
## Description
This PR contains a set of changes to move important interfaces and data types into the `./internal/model` package.
The criteria for including an interface or data type in here is roughly that the type should be important and used by several packages. We are especially interested to move more interfaces here to increase modularity.
An additional side effect is that, by reading this package, one should be able to understand more quickly how different parts of the codebase interact with each other.
This is what I want to move in `internal/model`:
- [x] most important interfaces from `internal/netxlite`
- [x] everything that was previously part of `internal/engine/model`
- [x] mocks from `internal/netxlite/mocks` should also be moved in here as a subpackage
When preparing a tutorial for netxlite, I figured it is easier
to tell people "hey, this is the package you should use for all
low-level networking stuff" rather than introducing people to
a set of packages working together where some piece of functionality
is here and some other piece is there.
Part of https://github.com/ooni/probe/issues/1591
The legacy part for now is internal/errorsx. It will stay there until
I figure out whether it also needs some extra bug fixing.
The good part is now in internal/netxlite/errorsx and contains all the
logic for mapping errors. We need to further improve upon this logic
by writing more thorough integration tests for QUIC.
We also need to copy the various dialer, conn, etc adapters that set
errors. We will put them inside netxlite and we will generate errors in
a way that is less crazy with respect to the major operation. (The
idea is to always wrap, given that now we measure in an incremental way
and we don't measure every operation together.)
Part of https://github.com/ooni/probe/issues/1591
This is how I did it:
1. `git clone https://github.com/ooni/probe-engine internal/engine`
2. ```
(cd internal/engine && git describe --tags)
v0.23.0
```
3. `nvim go.mod` (merging `go.mod` with `internal/engine/go.mod`
4. `rm -rf internal/.git internal/engine/go.{mod,sum}`
5. `git add internal/engine`
6. `find . -type f -name \*.go -exec sed -i 's@/ooni/probe-engine@/ooni/probe-cli/v3/internal/engine@g' {} \;`
7. `go build ./...` (passes)
8. `go test -race ./...` (temporary failure on RiseupVPN)
9. `go mod tidy`
10. this commit message
Once this piece of work is done, we can build a new version of `ooniprobe` that
is using `internal/engine` directly. We need to do more work to ensure all the
other functionality in `probe-engine` (e.g. making mobile packages) are still WAI.
Part of https://github.com/ooni/probe/issues/1335
