Function get_otel_context 

pub fn get_otel_context(span_id: &Id, dispatch: &Dispatch) -> Option<Context>

Utility functions to allow tracing::span::Ids to return OpenTelemetry Contexts. Note that this will internally try to lock Extensions so the caller must not be holding ExtensionsMut when calling this, otherwise the method may deadlock.

Extracts the OpenTelemetry Context associated with this span.

This method retrieves the OpenTelemetry context data that has been stored for the span by the OpenTelemetry layer. The context includes the span’s OpenTelemetry span context, which contains trace ID, span ID, and other trace-related metadata.

Examples

use tracing_opentelemetry::get_otel_context;
use tracing::dispatcher::WeakDispatch;
use tracing_subscriber::registry::LookupSpan;
use opentelemetry::trace::TraceContextExt;

fn do_things_with_otel_context<'a, D>(
    span_ref: &tracing_subscriber::registry::SpanRef<'a, D>,
    weak_dispatch: &WeakDispatch
) where
    D: LookupSpan<'a>,
{
    if let Some(dispatch) = weak_dispatch.upgrade() {
        // Be sure *NOT* to hold `ExtensionsMut` when calling this.
        if let Some(otel_context) = get_otel_context(&span_ref.id(), &dispatch) {
            // Process the extracted context
            let span = otel_context.span();
            let span_context = span.span_context();
            if span_context.is_valid() {
                // Handle the valid context...
            }
        }
    }
}

Use Cases

• When working with multiple subscriber configurations
• When implementing advanced tracing middleware that manages multiple dispatches