Trait tracing_opentelemetry::OpenTelemetrySpanExt

pub trait OpenTelemetrySpanExt {
    fn set_parent(&self, cx: Context);
    fn context(&self) -> Context;
}

Utility functions to allow tracing Spans to accept and return OpenTelemetry Contexts.

Required methods

fn set_parent(&self, cx: Context)

Associates self with a given OpenTelemetry trace, using the provided parent Context.

Examples

use opentelemetry::{propagation::TextMapPropagator, trace::TraceContextExt};
use opentelemetry::sdk::propagation::TraceContextPropagator;
use tracing_opentelemetry::OpenTelemetrySpanExt;
use std::collections::HashMap;
use tracing::Span;

// Example carrier, could be a framework header map that impls otel's `Extract`.
let mut carrier = HashMap::new();

// Propagator can be swapped with b3 propagator, jaeger propagator, etc.
let propagator = TraceContextPropagator::new();

// Extract otel parent context via the chosen propagator
let parent_context = propagator.extract(&carrier);

// Generate a tracing span as usual
let app_root = tracing::span!(tracing::Level::INFO, "app_start");

// Assign parent trace from external context
app_root.set_parent(parent_context.clone());

// Or if the current span has been created elsewhere:
Span::current().set_parent(parent_context);

fn context(&self) -> Context

Extracts an OpenTelemetry Context from self.

Examples

use opentelemetry::Context;
use tracing_opentelemetry::OpenTelemetrySpanExt;
use tracing::Span;

fn make_request(cx: Context) {
    // perform external request after injecting context
    // e.g. if the request's headers impl `opentelemetry::propagation::Injector`
    // then `propagator.inject_context(cx, request.headers_mut())`
}

// Generate a tracing span as usual
let app_root = tracing::span!(tracing::Level::INFO, "app_start");

// To include tracing context in client requests from _this_ app,
// extract the current OpenTelemetry context.
make_request(app_root.context());

// Or if the current span has been created elsewhere:
make_request(Span::current().context())

Implementations on Foreign Types

impl OpenTelemetrySpanExt for Span

fn set_parent(&self, cx: Context)

fn context(&self) -> Context

Implementors