otel-log-wrapper

Zero-config OpenTelemetry setup for Rust services that use tracing.

This crate wraps init-tracing-opentelemetry with the one-line initialization style used by qrt-log-utils.

No-Brain Init

otel_log_wrapper::init!()?;
tracing::info!("service started");

The macro derives the service metadata from the calling crate:

• service.name: env!("CARGO_PKG_NAME")
• service.version: env!("CARGO_PKG_VERSION")

Builder Init

Use the builder when you want an explicit service name or config.

use otel_log_wrapper::LoggerConfig;

LoggerConfig::builder("my-service").init()?;

With build metadata from shadow-rs:

shadow_rs::shadow!(build);

otel_log_wrapper::LoggerConfig::builder("my-service")
    .service_version(build::PKG_VERSION)
    .commit_short(build::SHORT_COMMIT)
    .commit_hash(build::COMMIT_HASH)
    .branch(build::BRANCH)
    .build_time(build::BUILD_TIME)
    .init()?;

otel-log-wrapper does not depend on shadow-rs; it only accepts the static strings generated by the application.

Build metadata is merged into OTEL_RESOURCE_ATTRIBUTES before initialization, so the OpenTelemetry SDK picks it up as resource attributes.

Defaults

The default setup:

• sets OTEL_SERVICE_NAME from the service name when unset
• sets OTEL_EXPORTER_OTLP_ENDPOINT to http://localhost:4317 when unset
• sets OTEL_EXPORTER_OTLP_PROTOCOL to grpc when unset
• respects RUST_LOG, then OTEL_LOG_LEVEL, then falls back to info
• uses human-readable stdout logs by default
• initializes a global tracing-subscriber
• exports OpenTelemetry traces and metrics
• prints a one-line startup message

Example startup message:

otel-log-wrapper init service=my-service version=0.1.0 commit=abc1234 endpoint=http://localhost:4317 protocol=grpc format=human metrics=true level=RUST_LOG|OTEL_LOG_LEVEL|info

Customization

use otel_log_wrapper::{LoggerConfig, LoggerFormat};
use tracing::level_filters::LevelFilter;

LoggerConfig::builder("my-service")
    .endpoint("http://collector:4317")
    .format(LoggerFormat::Json)
    .default_level(LevelFilter::INFO)
    .startup_message(false)
    .init()?;

Available formats:

• LoggerFormat::Human
• LoggerFormat::Pretty
• LoggerFormat::Full
• LoggerFormat::Compact
• LoggerFormat::Json

If you want to own shutdown explicitly instead of storing a global guard:

let _guard = LoggerConfig::builder("my-service")
    .global_subscriber(false)
    .init_guard()?;