OpenTracing
OpenTracing is a vendor-neutral API for distributed tracing instrumentation. It defined a common way for tracing libraries to describe spans, traces, and context propagation.
What It Provided
- A standard API for tracing libraries.
- A shared vocabulary for spans, traces, tags, and baggage.
- A way to instrument applications without locking into one vendor.
Core Terms
- Trace: the full request path.
- Span: a single timed operation.
- Tags: indexed metadata attached to spans.
- Baggage: context that travels with the trace across process boundaries.
Why It Matters
- Legacy systems may still expose OpenTracing instrumentation.
- Jaeger and other tracing backends historically integrated with it.
- It is useful for understanding older tracing code and terminology.
Practical Notes
- OpenTelemetry is the more common modern successor.
- The mental model is still useful even when the implementation changes.
- Keep trace context propagation consistent across HTTP, RPC, and messaging boundaries.