README.md

Getting started with OpenTelemetry Rust Logging

This example demonstrates the basics of logging with OpenTelemetry in Rust. If you're new to OpenTelemetry logging, this is a great place to start!

Understanding OpenTelemetry Logging

Important: OpenTelemetry does not provide its own end-user facing logging API. Instead, it integrates with existing, popular logging libraries in the Rust ecosystem. This example uses the tracing crate, one of the most widely-used logging frameworks in Rust.

The way this works is through a log appender (or bridge) - in this case, the opentelemetry-appender-tracing crate. The appender captures logs emitted through the tracing crate and forwards them to OpenTelemetry's logging pipeline.

What This Example Does

This example:

1. Sets up an OpenTelemetry LoggerProvider with resource attributes (like service name)
2. Configures a stdout exporter to output logs to the console (for simplicity)
3. Bridges the tracing crate to OpenTelemetry using opentelemetry-appender-tracing
4. Emits a sample log event using the tracing library's error! macro
5. Properly shuts down the logging pipeline

Note on Exporters: This example uses the stdout exporter for demonstration purposes. In production scenarios, you would typically use other exporters such as:

• OTLP exporter (opentelemetry-otlp) to send logs to an OpenTelemetry Collector or compatible backend
• Other vendor-specific exporters for your observability platform

Usage

Run the example to see logs emitted through the tracing crate being captured and output via OpenTelemetry:

cargo run

You'll see the log output in your console, demonstrating how OpenTelemetry captures and processes logs from the tracing library.