CrashLogger.kt

package com.sample.crashlogger

import android.content.Context
import android.os.Environment
import android.util.Log
import org.apache.commons.io.FileUtils
import org.apache.commons.lang.exception.ExceptionUtils
import java.io.File
import java.io.IOException
import java.nio.charset.StandardCharsets
import java.text.SimpleDateFormat
import java.util.*

private val tag = "CrashLogger"
private val directoryName = "/crash-logs"
private val iso8601DateFormat = SimpleDateFormat("yyyy-MM-dd-HH-mm-ss", Locale.US)

object CrashLogger {
    var initialized = false
    lateinit var logDirectory: File
    private lateinit var applicationId: String
    private lateinit var applicationVersion: String
    private val defaultUncaughtExceptionHandler: Thread.UncaughtExceptionHandler = Thread.getDefaultUncaughtExceptionHandler()

    fun initialize(context: Context) {
        if (initialized) return

        logDirectory = File(context.filesDir, directoryName)
        applicationId = context.packageName
        applicationVersion = context.packageManager.getPackageInfo(context.packageName, 0).versionName ?: "1"

        Thread.setDefaultUncaughtExceptionHandler { thread, throwable ->
            logToDirectory(throwable)
            defaultUncaughtExceptionHandler.uncaughtException(thread, throwable)
        }

        initialized = true
    }

    fun logToDirectory(throwable: Throwable) {
        val fileName = "$applicationId-" +
                "v$applicationVersion-" +
                "crash-" +
                "${iso8601DateFormat.format(Date())}.txt"

        val outputFile = File(logDirectory, fileName)

        try {
            FileUtils.write(outputFile, ExceptionUtils.getStackTrace(throwable), StandardCharsets.UTF_8)
        } catch (e: IOException) {
            Log.e(tag, "Failed to write crash log file: $fileName", e)
        }
    }

    fun export() {
        val externalLogDir = File(
                Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS),
                directoryName)

        try {
            FileUtils.copyDirectory(logDirectory, externalLogDir)
            logDirectory.listFiles().filter { !it.isDirectory }.forEach { it.delete() }
        } catch (e: IOException) {
            Log.e(tag, "Failed to export log files", e)
        }
    }
}