First Commit

libraries/featureflag/api/build.gradle.kts

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 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.
+ */
+
+plugins {
+    id("io.element.android-library")
+}
+
+android {
+    namespace = "io.element.android.libraries.featureflag.api"
+}
+
+dependencies {
+    implementation(projects.appconfig)
+    implementation(projects.libraries.core)
+    implementation(libs.coroutines.core)
+}

libraries/featureflag/api/src/main/kotlin/io/element/android/libraries/featureflag/api/Feature.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 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.libraries.featureflag.api
+
+import io.element.android.libraries.core.meta.BuildMeta
+
+interface Feature {
+    /**
+     * Unique key to identify the feature.
+     */
+    val key: String
+
+    /**
+     * Title to show in the UI. Not needed to be translated as it's only dev accessible.
+     */
+    val title: String
+
+    /**
+     * Optional description to give more context on the feature.
+     */
+    val description: String?
+
+    /**
+     * Calculate the default value of the feature (enabled or disabled) given a [BuildMeta].
+     */
+    val defaultValue: (BuildMeta) -> Boolean
+
+    /**
+     * Whether the feature is finished or not.
+     * If false: the feature is still in development, it will appear in the developer options screen to be able to enable it and test it.
+     * If true: the feature is finished, it will not appear in the developer options screen.
+     */
+    val isFinished: Boolean
+
+    /**
+     * Whether the feature is only available in Labs (and not in developer options).
+     * Feature flags that set this to `true` can be enabled by any users, not only those that have enabled developer mode.
+     */
+    val isInLabs: Boolean
+}

libraries/featureflag/api/src/main/kotlin/io/element/android/libraries/featureflag/api/FeatureFlagService.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 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.libraries.featureflag.api
+
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.first
+
+interface FeatureFlagService {
+    /**
+     * @param feature the feature to check for
+     *
+     * @return true if the feature is enabled
+     */
+    suspend fun isFeatureEnabled(feature: Feature): Boolean = isFeatureEnabledFlow(feature).first()
+
+    /**
+     * @param feature the feature to check for
+     *
+     * @return a flow of booleans, true if the feature is enabled, false if it is disabled.
+     */
+    fun isFeatureEnabledFlow(feature: Feature): Flow<Boolean>
+
+    /**
+     * @param feature the feature to enable or disable
+     * @param enabled true to enable the feature
+     *
+     * @return true if the method succeeds, ie if a [io.element.android.libraries.featureflag.impl.MutableFeatureFlagProvider]
+     * is registered
+     */
+    suspend fun setFeatureEnabled(feature: Feature, enabled: Boolean): Boolean
+
+    /**
+     * @return the list of available features that can be toggled.
+     * @param includeFinishedFeatures whether to include finished features, default is false
+     * @param isInLabs whether the user is in labs (to include lab features), default is false
+     */
+    fun getAvailableFeatures(
+        includeFinishedFeatures: Boolean = false,
+        isInLabs: Boolean = false,
+    ): List<Feature>
+}

libraries/featureflag/api/src/main/kotlin/io/element/android/libraries/featureflag/api/FeatureFlags.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 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.libraries.featureflag.api
+
+import io.element.android.libraries.core.meta.BuildMeta
+import io.element.android.libraries.core.meta.BuildType
+
+/**
+ * To enable or disable a FeatureFlags, change the `defaultValue` value.
+ */
+enum class FeatureFlags(
+    override val key: String,
+    override val title: String,
+    override val description: String? = null,
+    override val defaultValue: (BuildMeta) -> Boolean,
+    override val isFinished: Boolean,
+    override val isInLabs: Boolean = false,
+) : Feature {
+    RoomDirectorySearch(
+        key = "feature.roomdirectorysearch",
+        title = "Room directory search",
+        description = "Allow user to search for public rooms in their homeserver",
+        defaultValue = { false },
+        isFinished = false,
+    ),
+    ShowBlockedUsersDetails(
+        key = "feature.showBlockedUsersDetails",
+        title = "Show blocked users details",
+        description = "Show the name and avatar of blocked users in the blocked users list",
+        defaultValue = { false },
+        isFinished = false,
+    ),
+    SyncOnPush(
+        key = "feature.syncOnPush",
+        title = "Sync on push",
+        description = "Subscribe to room sync when a push is received",
+        defaultValue = { true },
+        isFinished = false,
+    ),
+    OnlySignedDeviceIsolationMode(
+        key = "feature.onlySignedDeviceIsolationMode",
+        title = "Exclude insecure devices when sending/receiving messages",
+        description = "This setting controls how end-to-end encryption (E2E) keys are shared." +
+            " Enabling it will prevent the inclusion of devices that have not been explicitly verified by their owners." +
+            " You'll have to stop and re-open the app manually for that setting to take effect.",
+        defaultValue = { false },
+        isFinished = false,
+    ),
+    EnableKeyShareOnInvite(
+        key = "feature.enableKeyShareOnInvite",
+        title = "Share encrypted history with new members",
+        description = "When inviting a user to an encrypted room that has history visibility set to \"shared\"," +
+            " share encrypted history with that user, and accept encrypted history when you are invited to such a room." +
+            "\nRequires an app restart to take effect." +
+            "\n\nWARNING: this feature is EXPERIMENTAL and not all security precautions are implemented." +
+            " Do not enable on production accounts.",
+        defaultValue = { false },
+        isFinished = false,
+    ),
+    Knock(
+        key = "feature.knock",
+        title = "Ask to join",
+        description = "Allow creating rooms which users can request access to.",
+        defaultValue = { false },
+        isFinished = false,
+    ),
+    Space(
+        key = "feature.space",
+        title = "Spaces",
+        defaultValue = { true },
+        isFinished = false,
+    ),
+    PrintLogsToLogcat(
+        key = "feature.print_logs_to_logcat",
+        title = "Print logs to logcat",
+        description = "Print logs to logcat in addition to log files. Requires an app restart to take effect." +
+            "\n\nWARNING: this will make the logs visible in the device logs and may affect performance. " +
+            "It's not intended for daily usage in release builds.",
+        defaultValue = { buildMeta -> buildMeta.buildType != BuildType.RELEASE },
+        // False so it's displayed in the developer options screen
+        isFinished = false,
+    ),
+    SelectableMediaQuality(
+        key = "feature.selectable_media_quality",
+        title = "Select media quality per upload",
+        description = "You can select the media quality for each attachment you upload.",
+        defaultValue = { false },
+        // False so it's displayed in the developer options screen
+        isFinished = false,
+    ),
+    Threads(
+        key = "feature.thread_timeline",
+        title = "Threads",
+        description = "Renders thread messages as a dedicated timeline. Restarting the app is required for this setting to fully take effect.",
+        defaultValue = { false },
+        isFinished = false,
+        isInLabs = true,
+    ),
+    MultiAccount(
+        key = "feature.multi_account",
+        title = "Multi accounts",
+        description = "Allow the application to connect to multiple accounts at the same time." +
+            "\n\nWARNING: this feature is EXPERIMENTAL and UNSTABLE.",
+        defaultValue = { false },
+        isFinished = false,
+    ),
+    SyncNotificationsWithWorkManager(
+        key = "feature.sync_notifications_with_workmanager",
+        title = "Sync notifications with WorkManager",
+        description = "Use WorkManager to schedule notification sync tasks when a push is received." +
+            " This should improve reliability and battery usage.",
+        defaultValue = { true },
+        isFinished = false,
+    ),
+}