Generalize the http.user_agent attribute to user_agent.*

[trask]

What are you trying to achieve?

Generalize the http.user_agent attribute so it can be used by different semantic conventions.

Related to: #3097 (comment)

Additional context.

ECS already has user_agent.* namespace: https://www.elastic.co/guide/en/ecs/current/ecs-user_agent.html

If we want to follow ECS naming, we could rename http.user_agent to user_agent.original.

UPDATE This proposal is being made independent of ECS alignment.

[MSNev]

This probably makes sense longer term as browsers are freezing the user agent, so the basic meaning of http.user_agent will diminish over time.

[trask]

This probably makes sense longer term as browsers are freezing the user agent, so the basic meaning of http.user_agent will diminish over time.

any thoughts if there's a better name than user_agent.original given the upcoming changes? (or maybe original is ok, in the sense it's the original "old" field)

[mateuszrzeszutek]

Since we're planning to rename http.url to url.full, maybe user_agent.full? In case you want to parse the agent and split out individual properties (like ECS does).

[trask]

Since we're planning to rename http.url to url.full, maybe user_agent.full? In case you want to parse the agent and split out individual properties (like ECS does).

I think we'll only rename http.url to url.full if we are aligning with ECS, in which case we'd go with user_agent.original to also align with ECS

[trask]

I think this is a good change regardless of ECS alignment:

• we've already seen the need for generalizing this
• user agent string is being deprecated and replace with user agent components, so this will provide a good home for those under user_agent.* in the future
• breaking (renaming) http.user_agent should be less disruptive compared to making changes to other http.* attributes