Crash reports coming from hasFeature()

[marcshilling]

We are using "react-native-flagsmith": "1.6.2" in our production iOS/Android apps and we are seeing occasional crash reports coming from within your library on lines where we call flagsmith.hasFeature().

On Android devices it comes through as:

On iOS:

[dabeeeenster]

Hi @marcshilling - thanks for raising this. Are you able to provide some more info:

• Are you able to reproduce these errors locally?
• Is there any additional info in the full stack trace?
• Are you able to provide the get flags curl or JSON response you get from the API that generates this error?
• Is it repeatable or does it only happen from time to time?

[marcshilling]

Hey there @dabeeeenster.

• No, I've never gotten this locally...only seeing via Sentry crash reports from our production apps.
• The rest of the stack trace isn't really valuable...it's just our app's code tracing back from the line where we call hasFeature()...if you're curious: {flagsmith.hasFeature('ads_enabled') && <Advertisment />} to conditionally render an ad.
• I'm not sure about the API response because like I said I can't reproduce this and it's happening in react-native-flagsmith's code.
• We're only seeing this from a very small percentage of our users. In the last 14 days it's occurred 21 times for 4 iOS users and 106 times for 97 Android users when we have likely had over a half million users in that timeframe. The iOS users have different devices but all are on iOS 14.7.1. On Android it's a variety of devices on Android 9, 10, and 11.

For the time being we've wrapped our hasFeature() calls in a try/catch which hopefully resolve our app-side issues, but the error reports are still coming in from your module. Also, if it matters, we are on a self-hosted Flagsmith instance.

[dabeeeenster]

Are you able to log the response from the API that is causing the failures via the SDK somehow? @kyle-ssg are there any hooks for this? Ideally logging the JSON payload from the API?

[kyle-ssg]

This is fixed as of 1.6.7 of react-native-flagsmith and flagsmith. Basically this was a super slim usecase whereby the previous analytics events hadnt been read from local storage at the point when tracking new events.

[kyle-ssg]

@marcshilling Feel free to re-open this if you spot the issue after updating to this version 🙌