This diff re-implements the vanilla_tor experiment. This experiment was
part of the ooni/probe-legacy implementation.
The reference issue is https://github.com/ooni/probe/issues/803. We didn't
consider the possible improvements mentioned by the
https://github.com/ooni/probe/issues/803#issuecomment-598715694 comment,
which means we'll need to create a follow-up issue for them. We will
then decide whether, when, and how to implement those follow-up measurements
either into `vanilla_tor` or into the existing `tor` experiment.
This novel `vanilla_tor` implementation emits test_keys that are mostly
compatible with the original implementation, however:
1. the `timeout` is a `float64` rather than integer (but the default
timeout is an integer, so there are no JSON-visible changes);
2. the `tor_log` string is gone and replaced by the `tor_logs` list
of strings, which contains the same information;
3. the definition of `error` has been augmented to include the
case in which there is an unknown error;
4. the implementation of vanilla_tor mirrors closely the one of torsf
and we have taken steps to make the two implementations as comparable
as possible in terms of the generated JSON measurement.
The main reason why we replaced `tor_log` with `tor_logs` are:
1. that `torsf` already used that;
2. that reading the JSON is easier with this implementation compared to
an implementation where all logs are into the same string.
If one is processing the new data format using Python, then it will
not be difficult convert `tor_log` to `tor_logs`. In any case, because
we extract the most interesting fields (e.g., the percentage of the
bootstrap where tor fails), it seems that logs are probably more useful
as something you want to read in edge cases (I guess).
Also, because we want `torsf` and `vanilla_tor` to have similar JSONs,
we renamed `torsf`'s `default_timeout` to `timeout`. This change has little
to none real-world impact, because no stable version of OONI Probe has
ever shipped a `torsf` producing the `default_timeout` field.
Regarding the structure of this diff, we have:
1. factored code to parse tor logs into a separate package;
2. implemented `vanilla_tor` as a stripped down `torsf` and added further
changes to ensure compatibility with the previous `vanilla_tor`'s data format;
3. improved `torsf` to merge back the changes in `vanilla_tor`, so the two
data formats of the two experiments are as similar as possible.
We believe producing as similar as possible data formats helps anyone who's
reading measurements generated by both experiments.
We have retained/introduced `vanilla_tor`'s `error` field, which is not very
useful when one has a more precise failure but is still what `vanilla_tor`
used to emit, so it makes sense to also have this field.
In addition to changing the implementation, we also updated the specs.
As part of our future work, we may want to consider factoring the common code
of these two experiments into the same underlying support library.
This diff contains significant improvements over the previous
implementation of the torsf experiment.
We add support for configuring different rendezvous methods after
the convo at https://github.com/ooni/probe/issues/2004. In doing
that, I've tried to use a terminology that is consistent with the
names being actually used by tor developers.
In terms of what to do next, this diff basically instruments
torsf to always rendezvous using domain fronting. Yet, it's also
possible to change the rendezvous method from the command line,
when using miniooni, which allows to experiment a bit more. In the
same vein, by default we use a persistent tor datadir, but it's
also possible to use a temporary datadir using the cmdline.
Here's how a generic invocation of `torsf` looks like:
```bash
./miniooni -O DisablePersistentDatadir=true \
-O RendezvousMethod=amp \
-O DisableProgress=true \
torsf
```
(The default is `DisablePersistentDatadir=false` and
`RendezvousMethod=domain_fronting`.)
With this implementation, we can start measuring whether snowflake
and tor together can boostrap, which seems the most important thing
to focus on at the beginning. Understanding why the bootstrap most
often does not converge with a temporary datadir on Android devices
remains instead an open problem for now. (I'll also update the
relevant issues or create new issues after commit this.)
We also address some methodology improvements that were proposed
in https://github.com/ooni/probe/issues/1686. Namely:
1. we record the tor version;
2. we include the bootstrap percentage by reading the logs;
3. we set the anomaly key correctly;
4. we measure the bytes send and received (by `tor` not by `snowflake`, since
doing it for snowflake seems more complex at this stage).
What remains to be done is the possibility of including Snowflake
events into the measurement, which is not possible until the new
improvements at common/event in snowflake.git are included into a
tagged version of snowflake itself. (I'll make sure to mention
this aspect to @cohosh in https://github.com/ooni/probe/issues/2004.)
Reference issue: https://github.com/ooni/probe/issues/1917.
I needed to change the summary key type returned by `torsf` to be a value. It seems the DB layer assumes that. If we pass it a pointer, it panics because it's experiment a value rather than a pointer 🤷.
This diff contains the following changes and enhancements:
1. upgrade snowflake to v2
2. observe that we were not changing defaults from outside of snowflake.go, so remove code allowing to do that;
3. bump the timeout to 600 seconds (it seems 300 was not always enough based on my testing);
4. add useful knob to disable `torsf` progress (it's really annoying on console, we should do something about this);
5. ptx.go: avoid printing an error when the connection has just been closed;
6. snowflake: test AMP cache, see that it's not working currently, so leave it disabled.
Related issues: https://github.com/ooni/probe/issues/1845, https://github.com/ooni/probe/issues/1894, and https://github.com/ooni/probe/issues/1917.
## 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
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
