Behaviour and API for propagation of Context.
This module defines the
otel_propagator behaviour. Required callback functions:
An implementation of the
otel_propagator behaviour must implement the
extract/2 callbacks. Inject is passed a term, for example
the Span Context or Baggage, and returns a carrier, such as HTTP headers,
to use for propagation in a request.
Extract is passed the carrier, such as HTTP headers, and returns the term that will be set in the Context.
Propagation API Specification: https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/context/api-propagators.md
text_map_extract(TextMap) -> any()
text_map_inject(TextMap) -> any()