FirebaseAnalytics sessionID / sessionIDWithCompletion returning 0 occasionally without error?

[mikehardy]

Description

Hi there - been fuzzing the iOS platform in react-native-firebase with a new massively parallel test run feature in CI, and I've noticed that occasionally we get zeros back for analytics session ID - though that can't be a valid session can it?

We don't return a value if the error object is defined, so it appears this is an erroneous return value.

Heard internally @ Invertase that this turns up on FlutterFire occasionally as well, causing a CI run to false-negative and I assume would impact users as well. Plural of anecdote is anecdata not data, but that gives me a little more confidence this is a problem.

It only happens occasionally so it is likely something race-y in firebase-ios-sdk and I'm curious if

a) a zero session id with no error object is ever a valid combination?
b) if anyone else has seen this or I'm blazing trail here and it needs more investigation

I'm going to bend a zero return value to an error at the react-native-firebase layer as I assume the answer to item A above is "nope, that shouldn't happen..."

Our implementation is dead-simple:

https://github.com/invertase/react-native-firebase/blob/f8d5a9d5cc811d2601e0fc0f32b58ffdd98cfff2/packages/analytics/ios/RNFBAnalytics/RNFBAnalyticsModule.m#L128-L139

My latest test run where I saw this - failed with this zero sessionId / no-error combo 2 out of 30 runs

https://github.com/invertase/react-native-firebase/actions/runs/17225729926/job/48869796447#step:25:3873

Reproducing the issue

No response

Firebase SDK Version

12.1.0

Xcode Version

16.4.0

Installation Method

CocoaPods

Firebase Product(s)

Analytics

Targeted Platforms

iOS

Relevant Log Output

If using Swift Package Manager, the project's Package.resolved

Expand Package.resolved snippet

Replace this line with the contents of your Package.resolved.

If using CocoaPods, the project's Podfile.lock

The Podfile.lock was erroring on issue creation because it is too large.

Have no fear, it's generally available on github though :-)

https://github.com/invertase/react-native-firebase/blob/f8d5a9d5cc811d2601e0fc0f32b58ffdd98cfff2/tests/ios/Podfile.lock

[google-oss-bot]

I couldn't figure out how to label this issue, so I've labeled it for a human to triage. Hang tight.

[ryang1428]

Just curious if this has been seen at all for the native SDK? Our analytics team has recently reported an increase in missing ga_session_ids since we updated to the 11.11.0 release a few months back.