Unleash / unleash / 30364933705

87%

master: 91%

Build Type

push

github

Committed by web-flow

Commit Message

feat: emit SDK flavor metadata from frontend client

🐛 Issue: 
When running the frontend SDKs (Swift, Android) for testing the
OpenFeature integrations, we see flavor metadata set as "not-set" on
Prometheus metrics.

The frontend SDKs send flavor metadata as the `unleash-sdk-flavor`
header to the Frontend API with a POST to /api/frontend/client/metrics,
but that header currently goes nowhere.
 
The difference with backend API: the `registerBackendClient`emits the
`CLIENT_REGISTER` heartbeat that feeds the `client_sdk_versions`
counter, but on the frontend client side the `registerFrontendClient`
only calls `updateSeenClient` - without any heartbeat. Till now that
path doesn't emit the `CLIENT_REGISTER` heartbeat that feeds the
`client_sdk_versions `counter.

✍🏽 So, on this PR, we:
- update `registerFrontendClient` to emit the heartbeat from the
frontend path, as we do for the backend path
- add flavor metadata to `IFrontendClientApp`
- update `registerFrontendApiMetrics` to accept + thread the flavor
- update the controller to pass the headers to
`frontendApiService.registerFrontendApiMetrics()`
- add tests 🧪 to assert that the heartbeat fires with the flavor labels
when the flag is on
- add e2e tests 🧪 to check we record the sdk flavor from frontend
metrics headers

Coverage Stats

1966 of 2179 branches covered (90.22%)

5 of 5 new or added lines in 1 file covered. (100.0%)

1 existing line in 1 file now uncovered.

15714 of 18016 relevant lines covered (87.22%)

769.02 hits per line