1914ea7076
As relict from very early designs of `connlib`, the `Callbacks` trait is still present and defines how the host app receives events from a running `Session`. Callbacks are not a great design pattern however because they force the running code, i.e. `connlib`s event-loop to execute unknown code. For example, if that code panics, all of `connlib` is taken down. Additionally, not all consumers may want to receive events via callbacks. The GUI and headless client for example already have their own event-loop in which they process all kinds of things. Having to deal with the `Callbacks` interface introduces an odd indirection here. To fix this, we instead return an `EventStream` when constructing a `Session`. This essentially aligns the API of `Session` with that of a channel. You receive two handles, one for sending in commands and one for receiving events. A `Session` will automatically spawn itself onto the given runtime so progress is made even if one does not poll on these channel handles. This greatly simplifies the code: - We get to delete the `Callbacks` interface. - We can delete the threaded callback adapter. This was only necessary because we didn't want to block `connlib` with the handling of the event. By using a channel for events, this is automatically guaranteed. - The GUI and headless client can directly integrate the event handling in their event-loop, without having to create an indirection with a channel. - It is now clear that only the Apple and Android FFI layers actually use callbacks to communicate these events. - We net-delete 100 LoC
Rust development guide
Firezone uses Rust for all data plane components. This directory contains the Linux and Windows clients, and low-level networking implementations related to STUN/TURN.
We target the last stable release of Rust using rust-toolchain.toml.
If you are using rustup, that is automatically handled for you.
Otherwise, ensure you have the latest stable version of Rust installed.
Reading Client logs
The Client logs are written as JSONL for machine-readability.
To make them more human-friendly, pipe them through jq like this:
cd path/to/logs # e.g. `$HOME/.cache/dev.firezone.client/data/logs` on Linux
cat *.log | jq -r '"\(.time) \(.severity) \(.message)"'
Resulting in, e.g.
2024-04-01T18:25:47.237661392Z INFO started log
2024-04-01T18:25:47.238193266Z INFO GIT_VERSION = 1.0.0-pre.11-35-gcc0d43531
2024-04-01T18:25:48.295243016Z INFO No token / actor_name on disk, starting in signed-out state
2024-04-01T18:25:48.295360641Z INFO null
Benchmarking on Linux
The recommended way for benchmarking any of the Rust components is Linux' perf utility.
For example, to attach to a running application, do:
- Ensure the binary you are profiling is compiled with the
releaseprofile. sudo perf record -g --freq 10000 --pid $(pgrep <your-binary>).- Run the speed test or whatever load-inducing task you want to measure.
sudo perf script > profile.perf- Open profiler.firefox.com and load
profile.perf
Instead of attaching to a process with --pid, you can also specify the path to executable directly.
That is useful if you want to capture perf data for a test or a micro-benchmark.