Tracers

A tracer type represents a destination for Wombat to send tracing events to such as Jaeger.

When a tracer is configured all messages will be allocated a root span during ingestion that represents their journey through a Wombat pipeline. Many Wombat processors create spans, and so tracing is a great way to analyse the pathways of individual messages as they progress through a Wombat instance.

Some inputs, such as http_server and http_client, are capable of extracting a root span from the source of the message (HTTP headers). This is a work in progress and should eventually expand so that all inputs have a way of doing so.

Other inputs, such as kafka can be configured to extract a root span by using the extract_tracing_map field.

A tracer config section looks like this:

tracer:
  jaeger:
    agent_address: localhost:6831
    sampler_type: const
    sampler_param: 1

Caution

Although the configuration spec of this component is stable the format of spans, tags and logs created by Wombat is subject to change as it is tuned for improvement.