tracing/examples

Tracing Examples

This directory contains a collection of examples that demonstrate the use of the tracing ecosystem:

• tracing:
  • counters: Implements a very simple metrics system to demonstrate how subscribers can consume field values as typed data.
  • sloggish: A demo Subscriber implementation that mimics the output of slog-term's Compact formatter.
• tracing-attributes:
  • attrs-basic: A simple example of the #[instrument] attribute.
  • attrs-args: An example implementing a simple recursive calculation of Fibonacci numbers, to demonstrate how the #[instrument] attribute can record function arguments.
• tracing-subscriber:
  • fmt: Demonstrates the use of the fmt module in tracing-subscriber, which provides a subscriber implementation that logs traces to the console.
  • fmt-stderr: Demonstrates overriding the output stream used by the fmt subscriber.
  • subscriber-filter: Demonstrates the tracing-subscriber::filter module, which provides a layer which adds configurable filtering to a subscriber implementation.
  • tower-load: Demonstrates how dynamically reloadable filters can be used to debug a server under load in production.
• tracing-futures:
  • futures-proxy-server: Demonstrates the use of tracing-futures by implementing a simple proxy server, based on this example from tokio.
  • futures-spawn: A simple demonstration of the relationship between the spans representing spawned futures.
• tracing-tower:
  • tower-h2-client: Demonstrates the use of tracing-tower to instrument a simple tower-h2 HTTP/2 client (based on this example from tower-h2).
  • tower-h2-server: Demonstrates the use of tracing-tower to instrument a simple tower-h2 HTTP/2 server (based on this example from tower-h2).
• tracing-serde:
  • serde-yak-shave: Demonstrates the use of tracing-serde by implementing a subscriber that emits trace output as JSON.
• tracing-log:
  • hyper-echo: Demonstrates how tracing-log can be used to record unstructured logs from dependencies as tracing events, by instrumenting this example from hyper, and using tracing-log to record logs emitted by hyper.

The nightly-examples directory contains examples of how tracing can be used with async/await. These are kept separate as async/await is currently only available on nightly Rust toolchains.