daniel-oai 28b91c7c31 Honor the OTLP metrics temporality preference (#51220) ...

## Why

Some metrics backends require cumulative metrics, while configured OTLP exporters previously always used delta temporality.

## What changed

Read `OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE` for configured HTTP and gRPC metrics exporters. Accept `delta`, `cumulative`, and `lowmemory` case-insensitively, retaining delta for unset, empty, or unrecognized values. Document the setting and preserve existing temporality for the built-in Statsig exporter and runtime snapshots.

## Testing

Update the HTTP loopback test to set the preference in an isolated subprocess and assert that the exported counter uses cumulative aggregation temporality.

GitOrigin-RevId: ca212eea20054b947005d323186c8b9a819ace9d

2026-10-06 01:36:17 +00:00

..

harness

[codex] Use expect in integration tests (#28441)

2026-06-15 21:53:47 -07:00

suite

Honor the OTLP metrics temporality preference (#51220)

2026-10-06 01:36:17 +00:00

tests.rs

[codex] Use expect in integration tests (#28441)

2026-06-15 21:53:47 -07:00