GooglePlayDriver.java

// Copyright 2016 Google, Inc.
//
// 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.firebase.jobdispatcher;

import android.app.PendingIntent;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.support.annotation.NonNull;
import com.firebase.jobdispatcher.FirebaseJobDispatcher.ScheduleResult;

/**
 * GooglePlayDriver provides an implementation of Driver for devices with Google Play
 * services installed. This backend does not do any availability checks and any uses should be
 * guarded with a call to {@code GoogleApiAvailability#isGooglePlayServicesAvailable(android.content.Context)}
 *
 * @see <a href="https://developers.google.com/android/reference/com/google/android/gms/common/GoogleApiAvailability#isGooglePlayServicesAvailable(android.content.Context)">GoogleApiAvailability</a>
 */
public final class GooglePlayDriver implements Driver {
    static final String BACKEND_PACKAGE = "com.google.android.gms";
    private final static String ACTION_SCHEDULE = "com.google.android.gms.gcm.ACTION_SCHEDULE";

    private final static String BUNDLE_PARAM_SCHEDULER_ACTION = "scheduler_action";
    private final static String BUNDLE_PARAM_TAG = "tag";
    private final static String BUNDLE_PARAM_TOKEN = "app";
    private final static String BUNDLE_PARAM_COMPONENT = "component";

    private final static String SCHEDULER_ACTION_SCHEDULE_TASK = "SCHEDULE_TASK";
    private final static String SCHEDULER_ACTION_CANCEL_TASK = "CANCEL_TASK";
    private final static String SCHEDULER_ACTION_CANCEL_ALL = "CANCEL_ALL";
    private static final String INTENT_PARAM_SOURCE = "source";
    private static final String INTENT_PARAM_SOURCE_VERSION = "source_version";

    private static final int JOB_DISPATCHER_SOURCE_CODE = 1 << 3;
    private static final int JOB_DISPATCHER_SOURCE_VERSION_CODE = 1;

    private final JobValidator mValidator;
    /**
     * The application Context. Used to send broadcasts.
     */
    private final Context mContext;
    /**
     * A PendingIntent from this package. Passed inside the broadcast so the receiver can verify the
     * sender's package.
     */
    private final PendingIntent mToken;
    /**
     * Turns Jobs into Bundles.
     */
    private final GooglePlayJobWriter mWriter;
    /**
     * This is hardcoded to true to avoid putting an unnecessary dependency on the Google Play
     * services library.
     */
    //TODO: this is an unsatisfying solution
    private final boolean mAvailable = true;

    /**
     * Instantiates a new GooglePlayDriver.
     */
    public GooglePlayDriver(Context context) {
        mContext = context;
        mToken = PendingIntent.getBroadcast(context, 0, new Intent(), 0);
        mWriter = new GooglePlayJobWriter();
        mValidator = new DefaultJobValidator(context);
    }

    @Override
    public boolean isAvailable() {
        return mAvailable;
    }

    /**
     * Schedules the provided Job.
     */
    @Override
    @ScheduleResult
    public int schedule(@NonNull Job job) {
        mContext.sendBroadcast(createScheduleRequest(job));

        return FirebaseJobDispatcher.SCHEDULE_RESULT_SUCCESS;
    }

    @Override
    public int cancel(@NonNull String tag) {
        mContext.sendBroadcast(createCancelRequest(tag));

        return FirebaseJobDispatcher.CANCEL_RESULT_SUCCESS;
    }

    @Override
    public int cancelAll() {
        mContext.sendBroadcast(createBatchCancelRequest());

        return FirebaseJobDispatcher.CANCEL_RESULT_SUCCESS;
    }

    @NonNull
    protected Intent createCancelRequest(@NonNull String tag) {
        Intent cancelReq = createSchedulerIntent(SCHEDULER_ACTION_CANCEL_TASK);
        cancelReq.putExtra(BUNDLE_PARAM_TAG, tag);
        cancelReq.putExtra(BUNDLE_PARAM_COMPONENT, new ComponentName(mContext, getReceiverClass()));
        return cancelReq;
    }

    @NonNull
    protected Intent createBatchCancelRequest() {
        Intent cancelReq = createSchedulerIntent(SCHEDULER_ACTION_CANCEL_ALL);
        cancelReq.putExtra(BUNDLE_PARAM_COMPONENT, new ComponentName(mContext, getReceiverClass()));
        return cancelReq;
    }

    @NonNull
    protected Class<GooglePlayReceiver> getReceiverClass() {
        return GooglePlayReceiver.class;
    }

    @NonNull
    @Override
    public JobValidator getValidator() {
        return mValidator;
    }

    @NonNull
    private Intent createScheduleRequest(JobParameters job) {
        Intent scheduleReq = createSchedulerIntent(SCHEDULER_ACTION_SCHEDULE_TASK);
        scheduleReq.putExtras(mWriter.writeToBundle(job, scheduleReq.getExtras()));
        return scheduleReq;
    }

    @NonNull
    private Intent createSchedulerIntent(String schedulerAction) {
        Intent scheduleReq = new Intent(ACTION_SCHEDULE);

        scheduleReq.setPackage(BACKEND_PACKAGE);
        scheduleReq.putExtra(BUNDLE_PARAM_SCHEDULER_ACTION, schedulerAction);
        scheduleReq.putExtra(BUNDLE_PARAM_TOKEN, mToken);
        scheduleReq.putExtra(INTENT_PARAM_SOURCE, JOB_DISPATCHER_SOURCE_CODE);
        scheduleReq.putExtra(INTENT_PARAM_SOURCE_VERSION, JOB_DISPATCHER_SOURCE_VERSION_CODE);

        return scheduleReq;
    }
}