Home | History | Annotate | Download | only in backup 
      1 /*
      2  * Copyright (C) 2015 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.server.backup;
     18 
     19 import android.app.AlarmManager;
     20 import android.app.job.JobInfo;
     21 import android.app.job.JobParameters;
     22 import android.app.job.JobScheduler;
     23 import android.app.job.JobService;
     24 import android.content.ComponentName;
     25 import android.content.Context;
     26 import android.os.RemoteException;
     27 import android.util.Slog;
     28 
     29 import java.util.Random;
     30 
     31 /**
     32  * Job for scheduling key/value backup work.  This module encapsulates all
     33  * of the policy around when those backup passes are executed.
     34  */
     35 public class KeyValueBackupJob extends JobService {
     36     private static final String TAG = "KeyValueBackupJob";
     37     private static ComponentName sKeyValueJobService =
     38             new ComponentName("android", KeyValueBackupJob.class.getName());
     39     private static final int JOB_ID = 0x5039;
     40 
     41     // Once someone asks for a backup, this is how long we hold off until we find
     42     // an on-charging opportunity.  If we hit this max latency we will run the operation
     43     // regardless.  Privileged callers can always trigger an immediate pass via
     44     // BackupManager.backupNow().
     45     private static final long MAX_DEFERRAL = AlarmManager.INTERVAL_DAY;
     46 
     47     private static boolean sScheduled = false;
     48     private static long sNextScheduled = 0;
     49 
     50     public static void schedule(Context ctx, BackupManagerConstants constants) {
     51         schedule(ctx, 0, constants);
     52     }
     53 
     54     public static void schedule(Context ctx, long delay, BackupManagerConstants constants) {
     55         synchronized (KeyValueBackupJob.class) {
     56             if (sScheduled) {
     57                 return;
     58             }
     59 
     60             final long interval;
     61             final long fuzz;
     62             final int networkType;
     63             final boolean needsCharging;
     64 
     65             synchronized (constants) {
     66                 interval = constants.getKeyValueBackupIntervalMilliseconds();
     67                 fuzz = constants.getKeyValueBackupFuzzMilliseconds();
     68                 networkType = constants.getKeyValueBackupRequiredNetworkType();
     69                 needsCharging = constants.getKeyValueBackupRequireCharging();
     70             }
     71             if (delay <= 0) {
     72                 delay = interval + new Random().nextInt((int) fuzz);
     73             }
     74             if (BackupManagerService.DEBUG_SCHEDULING) {
     75                 Slog.v(TAG, "Scheduling k/v pass in " + (delay / 1000 / 60) + " minutes");
     76             }
     77             JobInfo.Builder builder = new JobInfo.Builder(JOB_ID, sKeyValueJobService)
     78                     .setMinimumLatency(delay)
     79                     .setRequiredNetworkType(networkType)
     80                     .setRequiresCharging(needsCharging)
     81                     .setOverrideDeadline(MAX_DEFERRAL);
     82             JobScheduler js = (JobScheduler) ctx.getSystemService(Context.JOB_SCHEDULER_SERVICE);
     83             js.schedule(builder.build());
     84 
     85             sNextScheduled = System.currentTimeMillis() + delay;
     86             sScheduled = true;
     87         }
     88     }
     89 
     90     public static void cancel(Context ctx) {
     91         synchronized (KeyValueBackupJob.class) {
     92             JobScheduler js = (JobScheduler) ctx.getSystemService(Context.JOB_SCHEDULER_SERVICE);
     93             js.cancel(JOB_ID);
     94             sNextScheduled = 0;
     95             sScheduled = false;
     96         }
     97     }
     98 
     99     public static long nextScheduled() {
    100         synchronized (KeyValueBackupJob.class) {
    101             return sNextScheduled;
    102         }
    103     }
    104 
    105     @Override
    106     public boolean onStartJob(JobParameters params) {
    107         synchronized (KeyValueBackupJob.class) {
    108             sNextScheduled = 0;
    109             sScheduled = false;
    110         }
    111 
    112         // Time to run a key/value backup!
    113         Trampoline service = BackupManagerService.getInstance();
    114         try {
    115             service.backupNow();
    116         } catch (RemoteException e) {}
    117 
    118         // This was just a trigger; ongoing wakelock management is done by the
    119         // rest of the backup system.
    120         return false;
    121     }
    122 
    123     @Override
    124     public boolean onStopJob(JobParameters params) {
    125         // Intentionally empty; the job starting was just a trigger
    126         return false;
    127     }
    128 
    129 }
    130