This diff addresses another point of https://github.com/ooni/probe/issues/1956:
> - [ ] observe that we're still using a bunch of private interfaces for common interfaces such as the `Dialer`, so we can get rid of these private interfaces and always use the ones in `model`, which allows us to remove a bunch of legacy wrappers
Additional cleanups may still be possible. The more I cleanup, the more I see
there's extra legacy code we can dispose of (which seems good?).
This commit completely removes the original netx implementation,
which was only used by `tor`, since this has changed in
https://github.com/ooni/probe-cli/pull/652.
The original netx implementation was my first attempt at performing
network measurements using Go. It started its life inside of the
https://github.com/ooni/netx repository. It was later merged into
the https://github.com/ooni/probe-engine repository. It finally
ended up into this repository when we merged probe-engine with it.
The main issue with the original implementation is that it was
a bit too complex and used channels where they were probably not
necessary. Because of that, later I introduced a second netx
implementation, which currently lives in ./internal/engine/netx.
The current netx implementation, the third one, lives in the
./internal/netxlite package. We are currently working to replace
the second implementation with the third one, but this is happening
at a slow pace. Also, the second implementation does not have big
maintenance concerns but it's just a bit too bureaucratic to use
since it involves creating lots of `Config` structures.
The reference issue is probably https://github.com/ooni/probe/issues/1688,
since this diff has been enabled by rewriting Tor to use `measurex`
(a library living on top of `netxlite`).
## 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 basically adapts already existing code inside websteps to
instead be into the netxlite package, where it belongs.
In the process, abstract the TLSDialer but keep a reference to the
previous name to avoid refactoring existing code (just for now).
While there, notice that the right name is CloseIdleConnections (i.e.,
plural not singular) and change the name.
While there, since we abstracted TLSDialer to be an interface, create
suitable factories for making a TLSDialer type from a Dialer and a
TLSHandshaker.
See https://github.com/ooni/probe/issues/1591
Like we did before for the resolver, a dialer should propagate the
request to close idle connections to underlying types.
See https://github.com/ooni/probe/issues/1591
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
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(netx/dialer): hide implementation complexity
This follows the blueprint of `module.Config` and `nodule.New`
described at https://github.com/ooni/probe/issues/1591.
* fix: ndt7 bug where we were not using the right resolver
* fix(legacy/netx): clarify irrelevant implementation change
* fix: improve comments
* fix(hhfm): do not use dialer.New b/c it breaks it
Unclear to me why this is happening. Still, improve upon the
previous situation by adding a timeout.
It does not seem a priority to look into this issue now.
