Selective emitting of events

[spencerdcarlson]

Is your feature request related to a problem? Please describe. I would like to send selective metrics instead of every query executed.

Describe the solution you'd like Optionally enable selective emitting of events via configurations

config :opentelemetry_ecto, 
  explicit_capture: true,
  capture_key: :capture,
  capture_value: true

# In my application that is a hot code path
# I care about this query's metrics
MyRepo.all(query, telemetry_options: [capture: true])

# Somewhere else in my application that is NOT a hot code path
# I don't care about this query, it's just noise and expensive to report and store
MyRepo.all(query)

In handle_event/4 if :explicit_capture is enabled we only emit events with the appropriate capture key and value

Describe alternatives you've considered I can't think of an alternative to conditionally emitting events besides implementing my own subscribe and handle_event/4

Additional context Every metric that you store and emit has a cost to it, I'm trying to limit that.

Would you welcome an MR that attempts to implement some version of this?

[tsloughter]

Would it work in your case if you could wrap the code that has queries you don't want to collect in a call to something like untraced that would be a macro like with_span but that disables any child spans from being sampled?