Semantic Conventions for HTTP

Status: Experimental, Feature-freeze

This document defines semantic conventions for HTTP spans, metrics and logs. They can be used for http and https schemes and various HTTP versions like 1.1, 2 and SPDY.

Warning Existing HTTP instrumentations that are using v1.20.0 of this document (or prior):

• SHOULD NOT change the version of the HTTP or networking conventions that they emit until the HTTP semantic conventions are marked stable (HTTP stabilization will include stabilization of a core set of networking conventions which are also used in HTTP instrumentations). Conventions include, but are not limited to, attributes, metric and span names, and unit of measure.
• SHOULD introduce an environment variable OTEL_SEMCONV_STABILITY_OPT_IN in the existing major version which is a comma-separated list of values. The only values defined so far are:
  • http - emit the new, stable HTTP and networking conventions, and stop emitting the old experimental HTTP and networking conventions that the instrumentation emitted previously.
  • http/dup - emit both the old and the stable HTTP and networking conventions, allowing for a seamless transition.
  • The default behavior (in the absence of one of these values) is to continue emitting whatever version of the old experimental HTTP and networking conventions the instrumentation was emitting previously.
  • Note: http/dup has higher precedence than http in case both values are present
• SHOULD maintain (security patching at a minimum) the existing major version for at least six months after it starts emitting both sets of conventions.
• SHOULD drop the environment variable in the next major version (stable next major version SHOULD NOT be released prior to October 1, 2023).

Semantic conventions for HTTP are defined for the following signals:

• HTTP Spans: Semantic Conventions for HTTP client and server spans.
• HTTP Metrics: Semantic Conventions for HTTP client and server metrics.