99e061f795
## Motivation Some Tracing examples, especially in unstable crates, were written against earlier versions of `tracing`. They don't always demonstrate the most idiomatic use of Tracing APIs. ## Solution This updates the examples to use newer Tracing APIs and syntax. Now, the examples will demonstrate the preferred idioms. Signed-off-by: Eliza Weisman <eliza@buoyant.io>
tracing-serde
An adapter for serializing tracing types using serde.
Overview
tracing-serde enables serializing tracing types using
serde. tracing is a framework for instrumenting Rust programs
to collect structured, event-based diagnostic information.
Traditional logging is based on human-readable text messages.
tracing gives us machine-readable structured diagnostic
information. This lets us interact with diagnostic data
programmatically. With tracing-serde, you can implement a
Subscriber to serialize your tracing types and make use of the
existing ecosystem of serde serializers to talk with distributed
tracing systems.
Serializing diagnostic information allows us to do more with our logged values. For instance, when working with logging data in JSON gives us pretty-print when we're debugging in development and you can emit JSON and tracing data to monitor your services in production.
The tracing crate provides the APIs necessary for instrumenting
libraries and applications to emit trace data.
Usage
First, add this to your Cargo.toml:
[dependencies]
tracing = "0.1"
tracing-serde = "0.1"
Next, add this to your crate:
#[macro_use]
extern crate tracing;
extern crate tracing_serde;
use tracing_serde::AsSerde;
Please read the tracing documentation
for more information on how to create trace data.
This crate provides the as_serde function, via the AsSerde trait,
which enables serializing the Attributes, Event, Id, Metadata,
and Record tracing values.
For the full example, please see the examples folder.
Implement a Subscriber to format the serialization of tracing
types how you'd like.
pub struct JsonSubscriber {
next_id: AtomicUsize, // you need to assign span IDs, so you need a counter
}
impl Subscriber for JsonSubscriber {
fn new_span(&self, attrs: &Attributes) -> Id {
let id = self.next_id.fetch_add(1, Ordering::Relaxed);
let id = Id::from_u64(id as u64);
let json = json!({
"new_span": {
"attributes": attrs.as_serde(),
"id": id.as_serde(),
}});
println!("{}", json);
id
}
// ...
}
After you implement your Subscriber, you can use your tracing
subscriber (JsonSubscriber in the above example) to record serialized
trace data.
License
This project is licensed under the MIT license.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Tokio by you, shall be licensed as MIT, without any additional terms or conditions.