add WorkManager extension

core_settings.gradle

@@ -38,6 +38,7 @@ include modulePrefix + 'extension-vp9'
 include modulePrefix + 'extension-rtmp'
 include modulePrefix + 'extension-leanback'
 include modulePrefix + 'extension-jobdispatcher'
+include modulePrefix + 'extension-workmanager'
 
 project(modulePrefix + 'library').projectDir = new File(rootDir, 'library/all')
 project(modulePrefix + 'library-core').projectDir = new File(rootDir, 'library/core')
@@ -60,3 +61,4 @@ project(modulePrefix + 'extension-vp9').projectDir = new File(rootDir, 'extensio
 project(modulePrefix + 'extension-rtmp').projectDir = new File(rootDir, 'extensions/rtmp')
 project(modulePrefix + 'extension-leanback').projectDir = new File(rootDir, 'extensions/leanback')
 project(modulePrefix + 'extension-jobdispatcher').projectDir = new File(rootDir, 'extensions/jobdispatcher')
+project(modulePrefix + 'extension-workmanager').projectDir = new File(rootDir, 'extensions/workmanager')

extensions/workmanager/README.md

@@ -0,0 +1,23 @@
+# ExoPlayer WorkManager extension #
+
+This extension provides a Scheduler implementation which uses [Android Arch WorkManager][].
+
+[Android Arch WorkManager]: https://developer.android.com/topic/libraries/architecture/workmanager.html
+
+## Getting the extension ##
+
+The easiest way to use the extension is to add it as a gradle dependency:
+
+```gradle
+implementation 'com.google.android.exoplayer:extension-workmanager:2.X.X'
+```
+
+where `2.X.X` is the version, which must match the version of the ExoPlayer
+library being used.
+
+Alternatively, you can clone the ExoPlayer repository and depend on the module
+locally. Instructions for doing this can be found in ExoPlayer's
+[top level README][].
+
+[top level README]: https://github.com/google/ExoPlayer/blob/release-v2/README.md
+

extensions/workmanager/build.gradle

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+apply from: '../../constants.gradle'
+apply plugin: 'com.android.library'
+
+android {
+    compileSdkVersion project.ext.compileSdkVersion
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    defaultConfig {
+        minSdkVersion project.ext.minSdkVersion
+        targetSdkVersion project.ext.targetSdkVersion
+    }
+
+    testOptions.unitTests.includeAndroidResources = true
+}
+
+dependencies {
+    implementation project(modulePrefix + 'library-core')
+    implementation 'android.arch.work:work-runtime:1.0.0'
+}
+
+ext {
+    javadocTitle = 'Android Arch WorkManager extension'
+}
+apply from: '../../javadoc_library.gradle'
+
+ext {
+    releaseArtifact = 'extension-workmanager'
+    releaseDescription = 'Android Arch WorkManager extension for ExoPlayer.'
+}
+apply from: '../../publish.gradle'

extensions/workmanager/src/main/AndroidManifest.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2018 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<manifest package="com.google.android.exoplayer2.ext.workmanager"/>

extensions/workmanager/src/main/java/com/google/android/exoplayer2/ext/workmanager/WorkManagerScheduler.java

@@ -0,0 +1,164 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.exoplayer2.ext.workmanager;
+
+import android.content.Context;
+import android.content.Intent;
+import android.os.Build;
+
+import com.google.android.exoplayer2.scheduler.Requirements;
+import com.google.android.exoplayer2.scheduler.Scheduler;
+import com.google.android.exoplayer2.util.Assertions;
+import com.google.android.exoplayer2.util.Log;
+import com.google.android.exoplayer2.util.Util;
+
+import androidx.annotation.NonNull;
+import androidx.work.Constraints;
+import androidx.work.Data;
+import androidx.work.ExistingWorkPolicy;
+import androidx.work.NetworkType;
+import androidx.work.OneTimeWorkRequest;
+import androidx.work.WorkManager;
+import androidx.work.Worker;
+import androidx.work.WorkerParameters;
+
+/***
+ * A {@link Scheduler} that uses {@link WorkManager}.
+ */
+public final class WorkManagerScheduler implements Scheduler {
+
+    private static final String TAG = "WorkManagerScheduler";
+    private static final String KEY_SERVICE_ACTION = "service_action";
+    private static final String KEY_SERVICE_PACKAGE = "service_package";
+    private static final String KEY_REQUIREMENTS = "requirements";
+
+    private final String workName;
+
+    /**
+     * @param workName A name for work scheduled by this instance. If the same name was used by a previous
+     *     instance, anything scheduled by the previous instance will be canceled by this instance if
+     *     {@link #schedule(Requirements, String, String)} or {@link #cancel()} are called.
+     */
+    public WorkManagerScheduler(String workName) {
+        this.workName = workName;
+    }
+
+    @Override
+    public boolean schedule(Requirements requirements, String servicePackage, String serviceAction) {
+        Constraints constraints = buildConstraints(requirements);
+        Data inputData = buildInputData(requirements, servicePackage, serviceAction);
+        OneTimeWorkRequest workRequest = buildWorkRequest(constraints, inputData);
+        logd("Scheduling work: " + workName);
+        WorkManager.getInstance().enqueueUniqueWork(workName, ExistingWorkPolicy.KEEP, workRequest);
+        return true;
+    }
+
+    @Override
+    public boolean cancel() {
+        logd("Canceling work: " + workName);
+        WorkManager.getInstance().cancelUniqueWork(workName);
+        return true;
+    }
+
+    private static Constraints buildConstraints(Requirements requirements) {
+        Constraints.Builder builder = new Constraints.Builder();
+
+        switch (requirements.getRequiredNetworkType()) {
+            case Requirements.NETWORK_TYPE_NONE:
+                builder.setRequiredNetworkType(NetworkType.NOT_REQUIRED);
+                break;
+            case Requirements.NETWORK_TYPE_ANY:
+                builder.setRequiredNetworkType(NetworkType.CONNECTED);
+                break;
+            case Requirements.NETWORK_TYPE_UNMETERED:
+                builder.setRequiredNetworkType(NetworkType.UNMETERED);
+                break;
+            default:
+                throw new UnsupportedOperationException();
+        }
+
+        if (requirements.isChargingRequired()) {
+            builder.setRequiresCharging(true);
+        }
+
+        if (requirements.isIdleRequired() && Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+            builder.setRequiresDeviceIdle(true);
+        }
+
+        return builder.build();
+    }
+
+    private static Data buildInputData(Requirements requirements, String servicePackage, String serviceAction) {
+        Data.Builder builder = new Data.Builder();
+
+        builder.putInt(KEY_REQUIREMENTS, requirements.getRequirements());
+        builder.putString(KEY_SERVICE_PACKAGE, servicePackage);
+        builder.putString(KEY_SERVICE_ACTION, serviceAction);
+
+        return builder.build();
+    }
+
+    private static OneTimeWorkRequest buildWorkRequest(Constraints constraints, Data inputData) {
+        OneTimeWorkRequest.Builder builder = new OneTimeWorkRequest.Builder(SchedulerWorker.class);
+
+        builder.setConstraints(constraints);
+        builder.setInputData(inputData);
+
+        return builder.build();
+    }
+
+    private static void logd(String message) {
+        if (DEBUG) {
+            Log.d(TAG, message);
+        }
+    }
+
+    /** A {@link Worker} that starts the target service if the requirements are met. */
+    public static final class SchedulerWorker extends Worker {
+
+        private final WorkerParameters workerParams;
+        private final Context context;
+
+        public SchedulerWorker(@NonNull Context context, @NonNull WorkerParameters workerParams) {
+            super(context, workerParams);
+            this.workerParams = workerParams;
+            this.context = context;
+        }
+
+        @NonNull
+        @Override
+        public Result doWork() {
+            logd("SchedulerWorker is started");
+            Data inputData = workerParams.getInputData();
+            Assertions.checkNotNull(inputData, "Work started without input data.");
+            Requirements requirements = new Requirements(inputData.getInt(KEY_REQUIREMENTS, 0));
+            if (requirements.checkRequirements(context)) {
+                logd("Requirements are met");
+                String serviceAction = inputData.getString(KEY_SERVICE_ACTION);
+                String servicePackage = inputData.getString(KEY_SERVICE_PACKAGE);
+                Assertions.checkNotNull(serviceAction, "Service action missing.");
+                Assertions.checkNotNull(servicePackage, "Service package missing.");
+                Intent intent = new Intent(serviceAction).setPackage(servicePackage);
+                logd("Starting service action: " + serviceAction + " package: " + servicePackage);
+                Util.startForegroundService(context, intent);
+                return Result.success();
+            } else {
+                logd("Requirements are not met");
+                return Result.retry();
+            }
+        }
+    }
+}