add conditions on custom attributes for spans + a new selector for graphql error

[bnjjj]

Currently the router does not set otel.status_description on spans. This is a special attribute that will also set the span status.

This means that even responses have errors or http status is not 200 spans are not flagged as an error.

To complicate matters further, other languages usually use exceptions and stack unwinding to set span status, both of which are not available to us in rust.

Example:

telemetry:
  instrumentation:
    spans: 
      router: 
        attributes:    
          otel.status_description: 
            static: "there was an error"
            condition:
              any:
              - not:
                  eq:
                  - response_status: code
                  - 200
              - eq:
                - on_graphql_error
                - true

This will allow the user to set the description to something if there was an issue.

Suggest implementing using the existing condition logic and add two new selectors. This would check http status and if there are 1 or more graphql errors.

Fixes #4336

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Checklist

Complete the checklist (and note appropriate exceptions) before the PR is marked ready-for-review.

• Changes are compatible¹
• Documentation² completed
• Performance impact assessed and acceptable
• Tests added and passing³
  • Unit Tests
  • Integration Tests
  • Manual Tests

Exceptions

Note any exceptions here

Notes

Footnotes

1. It may be appropriate to bring upcoming changes to the attention of other (impacted) groups. Please endeavour to do this before seeking PR approval. The mechanism for doing this will vary considerably, so use your judgement as to how and when to do this. ↩

2. Configuration is an important part of many changes. Where applicable please try to document configuration examples. ↩

3. Tick whichever testing boxes are applicable. If you are adding Manual Tests, please document the manual testing (extensively) in the Exceptions. ↩

[router-perf]

CI performance tests

• reload - Reload test over a long period of time at a constant rate of users
• events_big_cap_high_rate_callback - Stress test for events with a lot of users, deduplication enabled and high rate event with a big queue capacity using callback mode
• events_without_dedup_callback - Stress test for events with a lot of users and deduplication DISABLED using callback mode
• large-request - Stress test with a 1 MB request payload
• const - Basic stress test that runs with a constant number of users
• no-graphos - Basic stress test, no GraphOS.
• step-jemalloc-tuning - Clone of the basic stress test for jemalloc tuning
• events - Stress test for events with a lot of users and deduplication ENABLED
• events_callback - Stress test for events with a lot of users and deduplication ENABLED in callback mode
• events_big_cap_high_rate - Stress test for events with a lot of users, deduplication enabled and high rate event with a big queue capacity
• events_without_dedup - Stress test for events with a lot of users and deduplication DISABLED
• xxlarge-request - Stress test with 100 MB request payload
• xlarge-request - Stress test with 10 MB request payload
• step - Basic stress test that steps up the number of users over time

[github-actions]

@BrynCooke, please consider creating a changeset entry in /.changesets/. These instructions describe the process and tooling.

[Samjin]

Is there a way to add client error code or error message to Router or Supergraph span attributes with this? Currently trace view only shows Bad request without any other info.