First session is not created on application start

[surbhiia]

• First session will start when the first time anyone calls getSessionId(), until then we just have a default (id = "") session in place.

• And getSessionId() is only getting called when you call SessionIdSpanAppender the first time, so new session is created only when first trace is calling the span processor, not when application starts

I was able to vet the same with debugging the demo-app:

• Looks like when ActivityLifecycleInstrumentation is installed, it calls AppStartupTimer to emit the app start event, that's when SessionIdSpanAppender is called, which calls session.getSessionId() and leads to 1st session creation (attaching screenshot with debug stack trace for same):

• Solution: We can initialize the first session in the init block of SessionManagerImpl, that way session will start as soon as the SessionManagerImpl object is created in OpenTelemetryRumBuilder (which should be called in customer's application onCreate). Below is a stack trace showing when SessionManagerImpl is first called while debugging demo app:

[breedx-splk]

Thanks @surbhiia. There's a lot going on with this issue. Even though most concerns here are session related, I think it could help to foster discussion to have it broken down into a few separate single-issue issues.

[surbhiia]

Divided it into separate issues!