Appending text with the SentryFileWriter not possible

[Melle010]

Gradle Version

7.3

AGP Version

7.0.3

Code Minifier/Optimizer

Proguard

Version

3.1.5

Sentry SDK Version

6.4.2

Steps to Reproduce

Appending a text to an existing text file overwrites the previous line. As a result, our log files always consist of only one (the most recent) log message. While debugging I noticed that SentryFileWriter is used instead of Java's FileWriter:

You can test it with the following code:

init {
    appendToLogFile("log message 1")
    appendToLogFile("log message 2")
}

private fun appendToLogFile(message: String) {
    runCatching {
        FileWriter(getLogFile(), true).use {
            it.append("$message\n")
            it.flush()
        }
    }.onFailure {
        Timber.e(it, "Could not write to log file")
    }
}

Expected Result

A text file with the following content:

log message 1
log message 2

Actual Result

A text file with the following content:

log message 2

2022-10-13.txt

[romtsn]

Hey thanks for the report and the details, we'll take a look 👍

[romtsn]

This is indeed a very nasty bug 🙈 sorry for the troubles caused. The fix is on its way, and we'll release a new version of the gradle plugin to fix the auto-instrumentation as well. Thanks for the comprehensive report!

[romtsn]

hey @Melle010 we've released version 3.2.1 of the gradle plugin, which bumps sentry-android to 6.6.0 (where the actual fix is), please try it out and let us know if you still have issues. Thanks!

[Melle010]

Hi @romtsn, thank you for the fix. Yes, with gradle plugin version 3.2.1 and sentry-android version 6.6.0 the file writer works again as expected.