feat: async session manager

[mormubis]

Motivation

The Session Manager Revamp (SMR) will require our session manager to operate asynchronously and postpone the SDK initialization until the session is ready.

Changes

onReady callback in session manager that propagates through all places using the start of the session.

Test instructions

TBD

Checklist

• Tested locally
• Tested on staging
• Added unit tests for this change.
• Added e2e/integration tests for this change.

[cit-pr-commenter]

Bundles Sizes Evolution

📦 Bundle Name	Base Size	Local Size	𝚫	𝚫%	Status
Rum	165.85 KiB	166.14 KiB	+297 B	+0.17%	✅
Rum Profiler	4.33 KiB	4.33 KiB	0 B	0.00%	✅
Rum Recorder	24.48 KiB	24.48 KiB	0 B	0.00%	✅
Logs	56.21 KiB	56.42 KiB	+218 B	+0.38%	✅
Flagging	944 B	944 B	0 B	0.00%	✅
Rum Slim	123.05 KiB	123.33 KiB	+288 B	+0.23%	✅
Worker	23.63 KiB	23.63 KiB	0 B	0.00%	✅

🚀 CPU Performance

Action Name	Base CPU Time (ms)	Local CPU Time (ms)	𝚫%
RUM - add global context	0.0042	0.0126	+200.00%
RUM - add action	0.0128	0.031	+142.19%
RUM - add error	0.0131	0.0358	+173.28%
RUM - add timing	0.0025	0.0066	+164.00%
RUM - start view	0.0032	0.0087	+171.87%
RUM - start/stop session replay recording	0.0007	0.0021	+200.00%
Logs - log message	0.0157	0.0299	+90.45%

🧠 Memory Performance

Action Name	Base Memory Consumption	Local Memory Consumption	𝚫
RUM - add global context	25.67 KiB	26.31 KiB	+653 B
RUM - add action	49.89 KiB	89.80 KiB	+39.92 KiB
RUM - add timing	25.12 KiB	25.11 KiB	-16 B
RUM - add error	53.52 KiB	99.54 KiB	+46.02 KiB
RUM - start/stop session replay recording	24.03 KiB	25.09 KiB	+1.06 KiB
RUM - start view	424.27 KiB	438.32 KiB	+14.05 KiB
Logs - log message	45.55 KiB	96.06 KiB	+50.50 KiB

🔗 RealWorld

[datadog-official]

⚠️ Tests

✨ Fix all issues with Cursor

⚠️ Warnings

🧪 2 Tests failed

telemetry › collect errors related to session initialization › logs from telemetry.scenario.ts (Datadog) (Fix with Cursor)

createTest.ts:244:3 logs

[Edge] › ../lib/framework/createTest.ts:244:3 › telemetry › collect errors related to session initialization › logs 

    Error: expect(received).toHaveLength(expected)

    Expected length: 1
    Received length: 0
    Received array:  []

...

telemetry › collect errors related to session initialization › rum from telemetry.scenario.ts (Datadog) (Fix with Cursor)

createTest.ts:244:3 rum

[Edge] › ../lib/framework/createTest.ts:244:3 › telemetry › collect errors related to session initialization › rum 

    Error: expect(received).toHaveLength(expected)

    Expected length: 1
    Received length: 0
    Received array:  []

...

ℹ️ Info

❄️ No new flaky tests detected

🎯 Code Coverage
• Patch Coverage: 76.32%
• Overall Coverage: 77.17% (-0.09%)

View detailed report

_{This comment will be updated automatically if new data arrives.
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[BenoitZugmeyer]

suggestion: you can simplify all this as:

function check() {
  Promise.resolve().then(callback).then(handleResult, handleError)
}

And sometimes in the future:

function check() {
  Promise.try(callback).then(handleResult, handleError)
}

[BenoitZugmeyer]

question: not sure to understand why you put waitFor in many places. When I remove those waitFor, tests are still passing?

Also suggestion: use collectAsyncCalls instead of waitFor (it'll be more efficient)

await collectAsyncCalls(startLogs, 1)

[mormubis]

It was super flaky for me. Most of the time, it varies between 3 or 25 tests failing. So I chose to add waitFor everywhere.

[BenoitZugmeyer]

question: Why do we need this change?

[mormubis]

I noticed that the session manager inits before the tryInit, so it outside of the monitor call.