Provide unit conversion for common non-second duration instruments (TSH-20621) (copy #8415)

[mergify]

Customers of Apollo integrate their OTLP streams with various different observability platform providers that have varying levels of sophistication on how they ingest incoming data.

We have a migration blocking use case where we require the ability to have a metric stream be sent in units of milliseconds. If this was a brand new metric we wouldnt need to, but:

• The custom metric has existed for years on our Apollo Gateway based federated graph, emanating this metric as milliseconds and is defined as milliseconds in Datadog

• Our internal customers have significantly leveraged this metric over the years and there are 2,322 different datadog artifacts (dashboards, SLOs, monitors, etc) that use this metric, is referred 4,184 different times. We do not have the capacity of transitioning customers to a new metric that uses different units at this time, it would have to be a gradual process over time, after completion of our Router migration

• We need both Router and Gateway to be producing this metric as we migrate the remainder of traffic off our Gateway solution so that those using this metric to monitor the performance and availability of subgraphs have continuity throughout the migration of clients from the Gateway soluction to the Router solution.

• When attempting to send this metric via Router, it was observed that the values emanated from Router are 1000 times lower... the Datadog ingestion pipeline will not do unit conversion of incoming data to match how the metric is defined in the metric metadata.

• Therefore we need Router the ability for Router to emanate this metric in ms units. I am fine with verbiage in the documentation that one should strive to use second units for durations, and only use non-seconds when they uncover the reality of integrating with various OTLP ingesting systems requires some flexibility, especially for migrations where your customers may have heavily invested in a particular metric in their previous incarnation of a federated graph with Gateway.

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Checklist

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

• PR description explains the motivation for the change and relevant context for reviewing
• PR description links appropriate GitHub/Jira tickets (creating when necessary)
• Changeset is included for user-facing changes
• Changes are compatible¹
• Documentation² completed
• Performance impact assessed and acceptable
• Metrics and logs are added³ and documented
• Tests added and passing⁴
  • Unit tests
  • Integration tests
  • Manual tests, as necessary

Exceptions

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Notes

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This is an automatic copy of pull request #8415 done by [Mergify](https://mergify.com).

Footnotes

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

3. A lot of (if not most) features benefit from built-in observability and debug-level logs. Please read this guidance on metrics best-practices. ↩

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

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[apollo-librarian]

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* graphos/routing/(latest)/observability/router-telemetry-otel/enabling-telemetry/instruments.mdx

Build ID: ab192899b01ec0e981fdb229
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URL: https://www.apollographql.com/docs/deploy-preview/ab192899b01ec0e981fdb229