mowispace/react-native-logs

Logging to a log level with undefined transport causes app to crash

kalyncoose opened this issue · 2 comments

kalyncoose commented

Bug Description

After reading this section of the READ_ME, Logs Only In Development Mode, I was lead to believe that I could trick the __DEV__ false/else clause to use undefined for transport so that a Release variant of the app would not utilize logging at all. Unfortunately it causes the app to completely crash (go to home screen on the device) so it appears react-native-logs does not have any exception handling when it comes to attempting to log to a level where there is no transport setup.

Bug Reproduction

Here is the general pattern of what causes the app to crash:

  • Logger Config has:
    • transport: __DEV__ ? consoleTransport : undefined,
    • severity: __DEV__ ? 'info' : 'warn'
  • App starts up fine in Release variant, but when encounters a log.warn() it crashes to device's home screen

Proposed Solution

Add exception handling to react-native-logs internal library code so it does its own warning to console if this scenario occurs - rather than completely crashing the app.

Note: I am mostly just submitting this issue for others to read as a possibility for what happens when you use the logger config this way.

alessandro-bottamedi commented

Thanks, i've added an error handling for this. 5c0fea3

  • 👍1
kalyncoose commented

I'm just now getting around to testing this fix, and it appears if you continue to use undefined log transport config it will still cause an app crash (because your fix now does throw Error which I guess RN does not like since it is not caught anywhere). To workaround this issue, I tried instead defining transport in release mode as an empty function like so:

transport: __DEV__ ? consoleTransport : () => {},

This appears to prevent the app from crashing as the transport logic is happy and does not throw a JS/TS error. Let me know if you think this may have any adverse side effects that I should consider.

Thanks!