Store log files in subfolder based on the homeserver domain.

app/src/main/kotlin/io/element/android/x/initializer/PlatformInitializer.kt

@@ -10,11 +10,10 @@ package io.element.android.x.initializer
 import android.content.Context
 import android.system.Os
 import androidx.startup.Initializer
-import io.element.android.features.rageshake.api.reporter.BugReporter
+import io.element.android.features.rageshake.api.logs.createWriteToFilesConfiguration
 import io.element.android.libraries.architecture.bindings
 import io.element.android.libraries.featureflag.api.FeatureFlags
 import io.element.android.libraries.matrix.api.tracing.TracingConfiguration
-import io.element.android.libraries.matrix.api.tracing.WriteToFilesConfiguration
 import io.element.android.x.di.AppBindings
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.runBlocking
@@ -34,7 +33,7 @@ class PlatformInitializer : Initializer<Unit> {
         val logLevel = runBlocking { preferencesStore.getTracingLogLevelFlow().first() }
         val tracingConfiguration = TracingConfiguration(
             writesToLogcat = runBlocking { featureFlagService.isFeatureEnabled(FeatureFlags.PrintLogsToLogcat) },
-            writesToFilesConfiguration = defaultWriteToDiskConfiguration(bugReporter),
+            writesToFilesConfiguration = bugReporter.createWriteToFilesConfiguration(),
             logLevel = logLevel,
             extraTargets = listOf(ELEMENT_X_TARGET),
             traceLogPacks = runBlocking { preferencesStore.getTracingLogPacksFlow().first() },
@@ -45,14 +44,5 @@ class PlatformInitializer : Initializer<Unit> {
         Os.setenv("RUST_BACKTRACE", "1", true)
     }
 
-    private fun defaultWriteToDiskConfiguration(bugReporter: BugReporter): WriteToFilesConfiguration.Enabled {
-        return WriteToFilesConfiguration.Enabled(
-            directory = bugReporter.logDirectory().absolutePath,
-            filenamePrefix = "logs",
-            // Keep a maximum of 1 week of log files.
-            numberOfFiles = 7 * 24,
-        )
-    }
-
     override fun dependencies(): List<Class<out Initializer<*>>> = mutableListOf()
 }

appnav/src/main/kotlin/io/element/android/appnav/RootFlowNode.kt

@@ -36,6 +36,7 @@ import io.element.android.appnav.root.RootView
 import io.element.android.features.enterprise.api.EnterpriseService
 import io.element.android.features.login.api.LoginParams
 import io.element.android.features.rageshake.api.bugreport.BugReportEntryPoint
+import io.element.android.features.rageshake.api.reporter.BugReporter
 import io.element.android.features.signedout.api.SignedOutEntryPoint
 import io.element.android.features.viewfolder.api.ViewFolderEntryPoint
 import io.element.android.libraries.architecture.BackstackView
@@ -73,6 +74,7 @@ class RootFlowNode @AssistedInject constructor(
     private val signedOutEntryPoint: SignedOutEntryPoint,
     private val intentResolver: IntentResolver,
     private val oidcActionFlow: OidcActionFlow,
+    private val bugReporter: BugReporter,
 ) : BaseFlowNode<RootFlowNode.NavTarget>(
     backstack = BackStack(
         initialElement = NavTarget.SplashScreen,
@@ -123,6 +125,7 @@ class RootFlowNode @AssistedInject constructor(
 
     private fun switchToNotLoggedInFlow(params: LoginParams?) {
         matrixSessionCache.removeAll()
+        bugReporter.setLogDirectorySubfolder(null)
         backstack.safeRoot(NavTarget.NotLoggedInFlow(params))
     }
 

features/rageshake/api/build.gradle.kts

@@ -16,5 +16,6 @@ dependencies {
     implementation(projects.libraries.architecture)
     implementation(projects.libraries.designsystem)
     implementation(projects.libraries.androidutils)
+    implementation(projects.libraries.matrix.api)
     implementation(projects.libraries.uiStrings)
 }

features/rageshake/api/src/main/kotlin/io/element/android/features/rageshake/api/logs/WriteToFilesConfigurationFactory.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.rageshake.api.logs
+
+import io.element.android.features.rageshake.api.reporter.BugReporter
+import io.element.android.libraries.matrix.api.tracing.WriteToFilesConfiguration
+
+fun BugReporter.createWriteToFilesConfiguration(): WriteToFilesConfiguration {
+    return WriteToFilesConfiguration.Enabled(
+        directory = logDirectory().absolutePath,
+        filenamePrefix = "logs",
+        // Keep a maximum of 1 week of log files.
+        numberOfFiles = 7 * 24,
+    )
+}

features/rageshake/api/src/main/kotlin/io/element/android/features/rageshake/api/reporter/BugReporter.kt

@@ -34,6 +34,14 @@ interface BugReporter {
      */
     fun logDirectory(): File
 
+    /**
+     * Set the subfolder name for the log directory.
+     * This will create a subfolder in the log directory with the given name.
+     * It will also configure the Rust SDK to use this subfolder for its logs.
+     * If the name is null, the log files will be stored in the base folder for the logs.
+     */
+    fun setLogDirectorySubfolder(subfolderName: String?)
+
     /**
      * Set the current tracing log level.
      */

features/rageshake/impl/src/main/kotlin/io/element/android/features/rageshake/impl/reporter/DefaultBugReporter.kt

@@ -13,6 +13,7 @@ import androidx.core.net.toFile
 import androidx.core.net.toUri
 import com.squareup.anvil.annotations.ContributesBinding
 import io.element.android.appconfig.RageshakeConfig
+import io.element.android.features.rageshake.api.logs.createWriteToFilesConfiguration
 import io.element.android.features.rageshake.api.reporter.BugReporter
 import io.element.android.features.rageshake.api.reporter.BugReporterListener
 import io.element.android.features.rageshake.impl.crash.CrashDataStore
@@ -28,11 +29,14 @@ import io.element.android.libraries.di.ApplicationContext
 import io.element.android.libraries.di.SingleIn
 import io.element.android.libraries.matrix.api.MatrixClientProvider
 import io.element.android.libraries.matrix.api.SdkMetadata
+import io.element.android.libraries.matrix.api.auth.MatrixAuthenticationService
 import io.element.android.libraries.matrix.api.core.UserId
+import io.element.android.libraries.matrix.api.tracing.TracingService
 import io.element.android.libraries.network.useragent.UserAgentProvider
 import io.element.android.libraries.sessionstorage.api.SessionStore
 import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.runBlocking
 import kotlinx.coroutines.withContext
 import okhttp3.MediaType.Companion.toMediaTypeOrNull
 import okhttp3.OkHttpClient
@@ -71,6 +75,8 @@ class DefaultBugReporter @Inject constructor(
     private val bugReporterUrlProvider: BugReporterUrlProvider,
     private val sdkMetadata: SdkMetadata,
     private val matrixClientProvider: MatrixClientProvider,
+    private val tracingService: TracingService,
+    matrixAuthenticationService: MatrixAuthenticationService,
 ) : BugReporter {
     companion object {
         // filenames
@@ -81,7 +87,21 @@ class DefaultBugReporter @Inject constructor(
     private val logcatCommandDebug = arrayOf("logcat", "-d", "-v", "threadtime", "*:*")
     private var currentTracingLogLevel: String? = null
 
-    private val logCatErrFile = File(logDirectory().absolutePath, LOG_CAT_FILENAME)
+    private val logCatErrFile: File
+        get() = File(logDirectory(), LOG_CAT_FILENAME)
+    private val baseLogDirectory = File(context.cacheDir, LOG_DIRECTORY_NAME)
+    private var currentLogDirectory: File = baseLogDirectory
+
+    init {
+        val logSubfolder = runBlocking {
+            sessionStore.getLatestSession()
+        }?.userId?.substringAfter(":")
+        setCurrentLogDirectory(logSubfolder)
+        matrixAuthenticationService.listenToNewMatrixClients {
+            // When a new Matrix client is created, we update the tracing configuration to write to files
+            setLogDirectorySubfolder(it.userIdServerName())
+        }
+    }
 
     override suspend fun sendBugReport(
         withDevicesLogs: Boolean,
@@ -286,11 +306,24 @@ class DefaultBugReporter @Inject constructor(
     }
 
     override fun logDirectory(): File {
-        return File(context.cacheDir, LOG_DIRECTORY_NAME).apply {
+        return currentLogDirectory.apply {
             mkdirs()
         }
     }
 
+    override fun setLogDirectorySubfolder(subfolderName: String?) {
+        setCurrentLogDirectory(subfolderName)
+        tracingService.updateWriteToFilesConfiguration(createWriteToFilesConfiguration())
+    }
+
+    private fun setCurrentLogDirectory(subfolderName: String?) {
+        currentLogDirectory = if (subfolderName == null) {
+            baseLogDirectory
+        } else {
+            File(baseLogDirectory, subfolderName)
+        }
+    }
+
     suspend fun deleteAllFiles(predicate: (File) -> Boolean) {
         withContext(coroutineDispatchers.io) {
             getLogFiles()
@@ -325,11 +358,12 @@ class DefaultBugReporter @Inject constructor(
      * @return the file if the operation succeeds
      */
     override fun saveLogCat() {
-        if (logCatErrFile.exists()) {
+        val file = logCatErrFile
-            logCatErrFile.safeDelete()
+        if (file.exists()) {
+            file.safeDelete()
         }
         try {
-            logCatErrFile.writer().use {
+            file.writer().use {
                 getLogCatError(it)
             }
         } catch (error: OutOfMemoryError) {

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/tracing/TracingService.kt

@@ -11,4 +11,6 @@ import timber.log.Timber
 
 interface TracingService {
     fun createTimberTree(target: String): Timber.Tree
+
+    fun updateWriteToFilesConfiguration(config: WriteToFilesConfiguration)
 }

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/auth/RustMatrixAuthenticationService.kt

@@ -71,9 +71,9 @@ class RustMatrixAuthenticationService @Inject constructor(
     private var currentClient: Client? = null
     private var currentHomeserver = MutableStateFlow<MatrixHomeServerDetails?>(null)
 
-    private var newMatrixClientObserver: ((MatrixClient) -> Unit)? = null
+    private val newMatrixClientObservers = mutableListOf<(MatrixClient) -> Unit>()
     override fun listenToNewMatrixClients(lambda: (MatrixClient) -> Unit) {
-        newMatrixClientObserver = lambda
+        newMatrixClientObservers.add(lambda)
     }
 
     private fun rotateSessionPath(): SessionPaths {
@@ -155,7 +155,8 @@ class RustMatrixAuthenticationService @Inject constructor(
                         passphrase = pendingPassphrase,
                         sessionPaths = currentSessionPaths,
                     )
-                newMatrixClientObserver?.invoke(rustMatrixClientFactory.create(client))
+                val matrixClient = rustMatrixClientFactory.create(client)
+                newMatrixClientObservers.forEach { it.invoke(matrixClient) }
                 sessionStore.storeData(sessionData)
 
                 // Clean up the strong reference held here since it's no longer necessary
@@ -246,7 +247,8 @@ class RustMatrixAuthenticationService @Inject constructor(
                 pendingOAuthAuthorizationData?.close()
                 pendingOAuthAuthorizationData = null
 
-                newMatrixClientObserver?.invoke(rustMatrixClientFactory.create(client))
+                val matrixClient = rustMatrixClientFactory.create(client)
+                newMatrixClientObservers.forEach { it.invoke(matrixClient) }
                 sessionStore.storeData(sessionData)
 
                 // Clean up the strong reference held here since it's no longer necessary
@@ -290,7 +292,8 @@ class RustMatrixAuthenticationService @Inject constructor(
                         passphrase = pendingPassphrase,
                         sessionPaths = emptySessionPaths,
                     )
-                newMatrixClientObserver?.invoke(rustMatrixClientFactory.create(client))
+                val matrixClient = rustMatrixClientFactory.create(client)
+                newMatrixClientObservers.forEach { it.invoke(matrixClient) }
                 sessionStore.storeData(sessionData)
 
                 // Clean up the strong reference held here since it's no longer necessary

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/tracing/RustTracingService.kt

@@ -15,6 +15,7 @@ import io.element.android.libraries.matrix.api.tracing.TracingConfiguration
 import io.element.android.libraries.matrix.api.tracing.TracingService
 import io.element.android.libraries.matrix.api.tracing.WriteToFilesConfiguration
 import org.matrix.rustcomponents.sdk.TracingFileConfiguration
+import org.matrix.rustcomponents.sdk.reloadTracingFileWriter
 import timber.log.Timber
 import javax.inject.Inject
 
@@ -23,6 +24,12 @@ class RustTracingService @Inject constructor(private val buildMeta: BuildMeta) :
     override fun createTimberTree(target: String): Timber.Tree {
         return RustTracingTree(target = target, retrieveFromStackTrace = buildMeta.isDebuggable)
     }
+
+    override fun updateWriteToFilesConfiguration(config: WriteToFilesConfiguration) {
+        config.toTracingFileConfiguration()?.let {
+            reloadTracingFileWriter(it)
+        }
+    }
 }
 
 private fun LogLevel.toRustLogLevel(): org.matrix.rustcomponents.sdk.LogLevel {