test-span
A macro and utilities to do snapshot tests on tracing spans.
How to use
Refer to the tests for a more exhaustive list of features and behaviors:
use test_span::prelude::*;
#[test_span]
fn a_test() {
do_something();
// test_span provides your with three functions:
let spans = get_spans();
let logs = get_logs();
// you can get both in one call
let (spans, logs) = get_telemetry();
// This plays well with insta snapshots:
insta::assert_json_snapshot!(logs);
insta::assert_json_snapshot!(spans);
}
// Test span plays well with async
#[test_span(tokio::test)]
// you can specify the span / log level
// you would like to track like this:
#[level(tracing::Level::INFO)]
async fn an_sync_test() {
do_something_async().await;
// You still get access to each function
let spans = get_spans();
let logs = get_logs();
let (spans, logs) = get_telemetry();
}
Limitations
Spans and logs are hard to track across thread spawns. However we're providing you with a log dump you can check:
#[test_span]
fn track_across_threads() {
std::thread::spawn(|| {
tracing::info!("only in get_all_logs!");
})
.join()
.unwrap();
let logs = get_logs();
// not in get_logs()
assert!(!logs.contains_message("only in get_all_logs!");
// get_all_logs takes a filter Level
let all_logs = test_span::get_all_logs(&tracing::Level::INFO);
assert!(all_logs.contains_message("only in get_all_logs!"));
}
Contributing
More information can be found in the contribution docs
Licensed under either of [Apache License, Version 2.0](LICENSE-APACHE) or [MIT license](LICENSE-MIT) at your option. License
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this crate by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.