tokio-bin-process 0.1.0

Allows your integration tests to run your application under a separate process and assert on tokio-tracing events.

It is a little opinionated and by default will fail the test when a tracing warning or error occurs. However a specific warning or error can be allowed on a per test basis.

Example usage for an imaginary database project named cooldb:

/// you'll want a helper like this as you'll be creating this in every integration test.
use tokio_bin_process::event::Level;
use tokio_bin_process::BinProcess;
use tokio_bin_process::event_matcher::EventMatcher;
use std::time::Duration;

async fn cooldb_process() -> BinProcess {
// start the process
let mut process = BinProcess::start_with_args(
"cooldb", // The name of the crate in this workspace to run
"cooldb", // The name that BinProcess should prepend its forwarded logs with
&[
// provide any custom CLI args required
"--foo", "bar",
// tokio-bin-process relies on reading tracing json's output,
// so configure the application to produce that
"--log-format", "json"
],
)
.await;

// block asynchrounously until the application gives an event indicating that its ready
tokio::time::timeout(
Duration::from_secs(30),
process.wait_for(
&EventMatcher::new()
.with_level(Level::Info)
.with_target("cooldb")
.with_message("accepting inbound connections"),
),
)
.await
.unwrap();
process
}

#[tokio::test]
async fn test_some_functionality() {
// start the db
let cooldb = cooldb_process().await;

// connect to the db, do something and assert we get the expected result
perform_test();

// Shutdown the DB, asserting that no warnings or errors occured,
// but allow and expect a certain warning.
// A drop bomb ensures that the test will fail if we forget to call this method.
cooldb
.shutdown_and_then_consume_events(&[
EventMatcher::new()
.with_level(Level::Warn)
.with_target("cooldb::internal")
.with_message("The user did something silly that we want to warn about but is actually expected in this test case")
])
.await;
}