refactor: Use androidx.startup for startup activities (#762)

Move initialisation of WorkManager and Timber in to new `Initializer`
classes, managed by `androidx.startup`.

There's a false-positive `BadConfigurationProvider` lint message because
the `Configuration.Provider` is in the content provider and not the
application class.

app/lint-baseline.xml

@@ -73,6 +73,13 @@
             column="9"/>
     </issue>
 
+    <issue
+        id="BadConfigurationProvider"
+        message="Expected Application subtype to implement Configuration.Provider">
+        <location
+            file="src/main/java/app/pachli/PachliApplication.kt"/>
+    </issue>
+
     <issue
         id="SelectedPhotoAccess"
         message="Your app is currently not handling Selected Photos Access introduced in Android 14+"

app/src/main/AndroidManifest.xml

@@ -218,8 +218,22 @@
         <provider
             android:name="androidx.startup.InitializationProvider"
             android:authorities="${applicationId}.androidx-startup"
-            tools:node="remove" />
+            android:exported="false"
+            tools:node="merge">
 
+            <meta-data
+                android:name="app.pachli.initializer.DependencyGraphInitializer"
+                android:value="androidx.startup" />
+            <meta-data
+                android:name="app.pachli.initializer.TimberInitializer"
+                android:value="androidx.startup" />
+            <meta-data
+                android:name="app.pachli.initializer.WorkManagerInitializer"
+                android:value="androidx.startup" />
+            <meta-data
+                android:name="androidx.work.WorkManagerInitializer"
+                android:value="androidx.startup"
+                tools:node="remove" />
+        </provider>
     </application>
-
 </manifest>

app/src/main/java/app/pachli/PachliApplication.kt

@@ -19,14 +19,11 @@ package app.pachli
 
 import android.app.Application
 import android.content.Context
-import androidx.hilt.work.HiltWorkerFactory
 import androidx.work.Constraints
 import androidx.work.ExistingPeriodicWorkPolicy
 import androidx.work.PeriodicWorkRequestBuilder
 import androidx.work.WorkManager
 import app.pachli.components.notifications.createWorkerNotificationChannel
-import app.pachli.core.activity.LogEntryTree
-import app.pachli.core.activity.TreeRing
 import app.pachli.core.activity.initCrashReporter
 import app.pachli.core.preferences.AppTheme
 import app.pachli.core.preferences.NEW_INSTALL_SCHEMA_VERSION
@@ -50,18 +47,12 @@ import timber.log.Timber
 
 @HiltAndroidApp
 class PachliApplication : Application() {
-    @Inject
-    lateinit var workerFactory: HiltWorkerFactory
-
     @Inject
     lateinit var localeManager: LocaleManager
 
     @Inject
     lateinit var sharedPreferencesRepository: SharedPreferencesRepository
 
-    @Inject
-    lateinit var logEntryTree: LogEntryTree
-
     override fun attachBaseContext(base: Context?) {
         super.attachBaseContext(base)
 
@@ -83,12 +74,6 @@ class PachliApplication : Application() {
 
         Security.insertProviderAt(Conscrypt.newProvider(), 1)
 
-        when {
-            BuildConfig.DEBUG -> Timber.plant(Timber.DebugTree())
-            BuildConfig.FLAVOR_color == "orange" -> Timber.plant(TreeRing)
-        }
-        Timber.plant(logEntryTree)
-
         // Migrate shared preference keys and defaults from version to version.
         val oldVersion = sharedPreferencesRepository.getInt(PrefKeys.SCHEMA_VERSION, NEW_INSTALL_SCHEMA_VERSION)
         if (oldVersion != SCHEMA_VERSION) {
@@ -108,12 +93,8 @@ class PachliApplication : Application() {
 
         createWorkerNotificationChannel(this)
 
-        WorkManager.initialize(
-            this,
-            androidx.work.Configuration.Builder().setWorkerFactory(workerFactory).build(),
-        )
-
         val workManager = WorkManager.getInstance(this)
+
         // Prune the database every ~ 12 hours when the device is idle.
         val pruneCacheWorker = PeriodicWorkRequestBuilder<PruneCacheWorker>(12, TimeUnit.HOURS)
             .setConstraints(Constraints.Builder().setRequiresDeviceIdle(true).build())

app/src/main/java/app/pachli/di/InitializerEntryPoint.kt

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2024 Pachli Association
+ *
+ * This file is a part of Pachli.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Pachli is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Pachli; if not,
+ * see <http://www.gnu.org/licenses>.
+ */
+
+package app.pachli.di
+
+import android.content.Context
+import app.pachli.initializer.TimberInitializer
+import app.pachli.initializer.WorkManagerInitializer
+import dagger.hilt.EntryPoint
+import dagger.hilt.InstallIn
+import dagger.hilt.android.EntryPointAccessors
+import dagger.hilt.components.SingletonComponent
+
+/**
+ * Entry point that allows [androidx.startup.Initializer] implementations
+ * to inject their dependencies.
+ */
+@EntryPoint
+@InstallIn(SingletonComponent::class)
+interface InitializerEntryPoint {
+    fun inject(timberInitializer: TimberInitializer)
+    fun inject(workManagerInitializer: WorkManagerInitializer)
+
+    companion object {
+        fun resolve(context: Context): InitializerEntryPoint {
+            val appContext = context.applicationContext ?: throw IllegalStateException()
+            return EntryPointAccessors.fromApplication(
+                appContext,
+                InitializerEntryPoint::class.java,
+            )
+        }
+    }
+}

app/src/main/java/app/pachli/initializer/DependencyGraphInitializer.kt

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2024 Pachli Association
+ *
+ * This file is a part of Pachli.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Pachli is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Pachli; if not,
+ * see <http://www.gnu.org/licenses>.
+ */
+
+package app.pachli.initializer
+
+import android.content.Context
+import androidx.startup.Initializer
+import app.pachli.di.InitializerEntryPoint
+
+/** Empty root initializer other initialisers can depend on. */
+class DependencyGraphInitializer : Initializer<Unit> {
+    override fun create(context: Context) {
+        InitializerEntryPoint.resolve(context)
+    }
+
+    override fun dependencies(): List<Class<out Initializer<*>>> {
+        return emptyList()
+    }
+}

app/src/main/java/app/pachli/initializer/TimberInitializer.kt

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2024 Pachli Association
+ *
+ * This file is a part of Pachli.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Pachli is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Pachli; if not,
+ * see <http://www.gnu.org/licenses>.
+ */
+
+package app.pachli.initializer
+
+import android.content.Context
+import androidx.startup.Initializer
+import app.pachli.BuildConfig
+import app.pachli.core.activity.LogEntryTree
+import app.pachli.core.activity.TreeRing
+import app.pachli.di.InitializerEntryPoint
+import javax.inject.Inject
+import timber.log.Timber
+
+/** Initialise [Timber]. */
+class TimberInitializer : Initializer<Unit> {
+    @Inject
+    lateinit var logEntryTree: LogEntryTree
+
+    override fun create(context: Context) {
+        InitializerEntryPoint.resolve(context).inject(this)
+
+        when {
+            BuildConfig.DEBUG -> Timber.plant(Timber.DebugTree())
+            BuildConfig.FLAVOR_color == "orange" -> Timber.plant(TreeRing)
+        }
+        Timber.plant(logEntryTree)
+    }
+
+    override fun dependencies(): List<Class<out Initializer<*>>> {
+        return listOf(DependencyGraphInitializer::class.java)
+    }
+}

app/src/main/java/app/pachli/initializer/WorkManagerInitializer.kt

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2024 Pachli Association
+ *
+ * This file is a part of Pachli.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Pachli is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Pachli; if not,
+ * see <http://www.gnu.org/licenses>.
+ */
+
+package app.pachli.initializer
+
+import android.content.Context
+import androidx.hilt.work.HiltWorkerFactory
+import androidx.startup.Initializer
+import androidx.work.Configuration
+import androidx.work.WorkManager
+import app.pachli.di.InitializerEntryPoint
+import javax.inject.Inject
+
+/** Initialise [WorkManager] with a [HiltWorkerFactory]. */
+class WorkManagerInitializer : Initializer<WorkManager>, Configuration.Provider {
+    @Inject
+    lateinit var workerFactory: HiltWorkerFactory
+
+    override val workManagerConfiguration: Configuration
+        get() = Configuration.Builder().setWorkerFactory(workerFactory).build()
+
+    override fun create(context: Context): WorkManager {
+        InitializerEntryPoint.resolve(context).inject(this)
+
+        WorkManager.initialize(context, workManagerConfiguration)
+        return WorkManager.getInstance(context)
+    }
+
+    override fun dependencies(): List<Class<out Initializer<*>>> {
+        return listOf(
+            DependencyGraphInitializer::class.java,
+            TimberInitializer::class.java,
+        )
+    }
+}

gradle/libs.versions.toml

@@ -19,6 +19,7 @@ androidx-preference = "1.2.1"
 androidx-recyclerview = "1.3.2"
 androidx-sharetarget = "1.2.0"
 androidx-splashscreen = "1.0.1"
+androidx-startup = "1.1.1"
 androidx-swiperefresh-layout = "1.1.0"
 androidx-testing = "2.2.0"
 androidx-test-core-ktx = "1.5.0"
@@ -143,6 +144,7 @@ androidx-room-ktx = { module = "androidx.room:room-ktx", version.ref = "androidx
 androidx-room-testing = { module = "androidx.room:room-testing", version.ref = "androidx-room" }
 androidx-recyclerview = { module = "androidx.recyclerview:recyclerview", version.ref = "androidx-recyclerview" }
 androidx-sharetarget = { module = "androidx.sharetarget:sharetarget", version.ref = "androidx-sharetarget" }
+androidx-startup = { module = "androidx.startup:startup-runtime", version.ref = "androidx-startup" }
 androidx-swiperefreshlayout = { module = "androidx.swiperefreshlayout:swiperefreshlayout", version.ref = "androidx-swiperefresh-layout" }
 androidx-test-core-ktx = { module = "androidx.test:core-ktx", version.ref = "androidx-test-core-ktx" }
 androidx-test-junit = { module = "androidx.test.ext:junit", version.ref = "androidx-junit" }
@@ -235,8 +237,7 @@ androidx = ["androidx-core-ktx", "androidx-appcompat", "androidx-fragment-ktx",
     "androidx-constraintlayout", "androidx-paging-runtime-ktx", "androidx-viewpager2", "androidx-work-runtime-ktx",
     "androidx-core-splashscreen", "androidx-activity", "androidx-media3-exoplayer", "androidx-media3-exoplayer-dash",
     "androidx-media3-exoplayer-hls", "androidx-media3-exoplayer-rtsp", "androidx-media3-datasource-okhttp", "androidx-media3-ui",
-    "androidx-transition",
-    "android-material"]
+    "androidx-transition", "android-material", "androidx-startup"]
 filemojicompat = ["filemojicompat-core", "filemojicompat-ui", "filemojicompat-defaults"]
 glide = ["glide-core", "glide-okhttp3-integration", "glide-animation-plugin"]
 lint-api = ["kotlin-stdlib", "lint-api", "lint-checks"]