src/com/owncloud/android/files/services/FileObserverService.java

   1 /* ownCloud Android client application
   2  *   Copyright (C) 2012 Bartek Przybylski
   3  *
   4  *   This program is free software: you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License as published by
   6  *   the Free Software Foundation, either version 3 of the License, or
   7  *   (at your option) any later version.
   8  *
   9  *   This program is distributed in the hope that it will be useful,
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *   GNU General Public License for more details.
  13  *
  14  *   You should have received a copy of the GNU General Public License
  15  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  *
  17  */
  18
  19 package com.owncloud.android.files.services;
  20
  21 import java.io.File;
  22 import java.util.HashMap;
  23 import java.util.Map;
  24
  25 import com.owncloud.android.datamodel.FileDataStorageManager;
  26 import com.owncloud.android.datamodel.OCFile;
  27 import com.owncloud.android.db.ProviderMeta.ProviderTableMeta;
  28 import com.owncloud.android.files.OwnCloudFileObserver;
  29 import com.owncloud.android.operations.SynchronizeFileOperation;
  30 import com.owncloud.android.utils.FileStorageUtils;
  31
  32 import android.accounts.Account;
  33 import android.accounts.AccountManager;
  34 import android.app.Service;
  35 import android.content.BroadcastReceiver;
  36 import android.content.Context;
  37 import android.content.Intent;
  38 import android.content.IntentFilter;
  39 import android.database.Cursor;
  40 import android.os.Binder;
  41 import android.os.IBinder;
  42 import android.util.Log;
  43
  44 public class FileObserverService extends Service {
  45
  46     public final static int CMD_INIT_OBSERVED_LIST = 1;
  47     public final static int CMD_ADD_OBSERVED_FILE = 2;
  48     public final static int CMD_DEL_OBSERVED_FILE = 3;
  49
  50     public final static String KEY_FILE_CMD = "KEY_FILE_CMD";
  51     public final static String KEY_CMD_ARG_FILE = "KEY_CMD_ARG_FILE";
  52     public final static String KEY_CMD_ARG_ACCOUNT = "KEY_CMD_ARG_ACCOUNT";
  53
  54     private static String TAG = FileObserverService.class.getSimpleName();
  55
  56     private static Map<String, OwnCloudFileObserver> mObserversMap;
  57     private static DownloadCompletedReceiverBis mDownloadReceiver;
  58     private IBinder mBinder = new LocalBinder();
  59
  60     public class LocalBinder extends Binder {
  61         FileObserverService getService() {
  62             return FileObserverService.this;
  63         }
  64     }
  65
  66     @Override
  67     public void onCreate() {
  68         super.onCreate();
  69         mDownloadReceiver = new DownloadCompletedReceiverBis();
  70         IntentFilter filter = new IntentFilter();
  71         filter.addAction(FileDownloader.DOWNLOAD_ADDED_MESSAGE);
  72         filter.addAction(FileDownloader.DOWNLOAD_FINISH_MESSAGE);
  73         registerReceiver(mDownloadReceiver, filter);
  74
  75         mObserversMap = new HashMap<String, OwnCloudFileObserver>();
  76         //initializeObservedList();
  77     }
  78
  79
  80     @Override
  81     public void onDestroy() {
  82         super.onDestroy();
  83         unregisterReceiver(mDownloadReceiver);
  84         mObserversMap = null;   // TODO study carefully the life cycle of Services to grant the best possible observance
  85         Log.d(TAG, "Bye, bye");
  86     }
  87
  88
  89     @Override
  90     public IBinder onBind(Intent intent) {
  91         return mBinder;
  92     }
  93
  94     @Override
  95     public int onStartCommand(Intent intent, int flags, int startId) {
  96         // this occurs when system tries to restart
  97         // service, so we need to reinitialize observers
  98         if (intent == null) {
  99             initializeObservedList();
 100             return Service.START_STICKY;
 101         }
 102
 103         if (!intent.hasExtra(KEY_FILE_CMD)) {
 104             Log.e(TAG, "No KEY_FILE_CMD argument given");
 105             return Service.START_STICKY;
 106         }
 107
 108         switch (intent.getIntExtra(KEY_FILE_CMD, -1)) {
 109             case CMD_INIT_OBSERVED_LIST:
 110                 initializeObservedList();
 111                 break;
 112             case CMD_ADD_OBSERVED_FILE:
 113                 addObservedFile( (OCFile)intent.getParcelableExtra(KEY_CMD_ARG_FILE),
 114                                  (Account)intent.getParcelableExtra(KEY_CMD_ARG_ACCOUNT));
 115                 break;
 116             case CMD_DEL_OBSERVED_FILE:
 117                 removeObservedFile( (OCFile)intent.getParcelableExtra(KEY_CMD_ARG_FILE),
 118                                     (Account)intent.getParcelableExtra(KEY_CMD_ARG_ACCOUNT));
 119                 break;
 120             default:
 121                 Log.wtf(TAG, "Incorrect key given");
 122         }
 123
 124         return Service.START_STICKY;
 125     }
 126
 127
 128     /**
 129      * Read from the local database the list of files that must to be kept synchronized and
 130      * starts file observers to monitor local changes on them
 131      */
 132     private void initializeObservedList() {
 133         mObserversMap.clear();
 134         Cursor c = getContentResolver().query(
 135                 ProviderTableMeta.CONTENT_URI,
 136                 null,
 137                 ProviderTableMeta.FILE_KEEP_IN_SYNC + " = ?",
 138                 new String[] {String.valueOf(1)},
 139                 null);
 140         if (!c.moveToFirst()) return;
 141         AccountManager acm = AccountManager.get(this);
 142         Account[] accounts = acm.getAccounts();
 143         do {
 144             Account account = null;
 145             for (Account a : accounts)
 146                 if (a.name.equals(c.getString(c.getColumnIndex(ProviderTableMeta.FILE_ACCOUNT_OWNER)))) {
 147                     account = a;
 148                     break;
 149                 }
 150
 151             if (account == null) continue;
 152             FileDataStorageManager storage =
 153                     new FileDataStorageManager(account, getContentResolver());
 154             if (!storage.fileExists(c.getString(c.getColumnIndex(ProviderTableMeta.FILE_PATH))))
 155                 continue;
 156
 157             String path = c.getString(c.getColumnIndex(ProviderTableMeta.FILE_STORAGE_PATH));
 158             OwnCloudFileObserver observer =
 159                     new OwnCloudFileObserver(   path,
 160                                                 account,
 161                                                 getApplicationContext(),
 162                                                 OwnCloudFileObserver.CHANGES_ONLY);
 163             mObserversMap.put(path, observer);
 164             if (new File(path).exists()) {
 165                 observer.startWatching();
 166                 Log.d(TAG, "Started watching file " + path);
 167             }
 168
 169         } while (c.moveToNext());
 170         c.close();
 171     }
 172
 173
 174     /**
 175      * Registers the local copy of a remote file to be observed for local changes,
 176      * an automatically updated in the ownCloud server.
 177      *
 178      * This method does NOT perform a {@link SynchronizeFileOperation} over the file.
 179      *
 180      * TODO We are ignoring that, currently, a local file can be linked to different files
 181      * in ownCloud if it's uploaded several times. That's something pending to update: we
 182      * will avoid that the same local file is linked to different remote files.
 183      *
 184      * @param file      Object representing a remote file which local copy must be observed.
 185      * @param account   OwnCloud account containing file.
 186      */
 187     private void addObservedFile(OCFile file, Account account) {
 188         if (file == null) {
 189             Log.e(TAG, "Trying to add a NULL file to observer");
 190             return;
 191         }
 192         String localPath = file.getStoragePath();
 193         if (localPath == null || localPath.length() <= 0) { // file downloading / to be download for the first time
 194             localPath = FileStorageUtils.getDefaultSavePathFor(account.name, file);
 195         }
 196         OwnCloudFileObserver observer = mObserversMap.get(localPath);
 197         if (observer == null) {
 198             /// the local file was never registered to observe before
 199             observer = new OwnCloudFileObserver(    localPath,
 200                                                     account,
 201                                                     getApplicationContext(),
 202                                                     OwnCloudFileObserver.CHANGES_ONLY);
 203             mObserversMap.put(localPath, observer);
 204             Log.d(TAG, "Observer added for path " + localPath);
 205
 206             if (file.isDown()) {
 207                 observer.startWatching();
 208                 Log.d(TAG, "Started watching " + localPath);
 209             }   // else - the observance can't be started on a file not already down; mDownloadReceiver will get noticed when the download of the file finishes
 210         }
 211
 212     }
 213
 214
 215     /**
 216      * Unregisters the local copy of a remote file to be observed for local changes.
 217      *
 218      * Starts to watch it, if the file has a local copy to watch.
 219      *
 220      * TODO We are ignoring that, currently, a local file can be linked to different files
 221      * in ownCloud if it's uploaded several times. That's something pending to update: we
 222      * will avoid that the same local file is linked to different remote files.
 223      *
 224      * @param file      Object representing a remote file which local copy must be not observed longer.
 225      * @param account   OwnCloud account containing file.
 226      */
 227     private void removeObservedFile(OCFile file, Account account) {
 228         if (file == null) {
 229             Log.e(TAG, "Trying to remove a NULL file");
 230             return;
 231         }
 232         String localPath = file.getStoragePath();
 233         if (localPath == null || localPath.length() <= 0) {
 234             localPath = FileStorageUtils.getDefaultSavePathFor(account.name, file);
 235         }
 236
 237         OwnCloudFileObserver observer = mObserversMap.get(localPath);
 238         if (observer != null) {
 239             observer.stopWatching();
 240             mObserversMap.remove(observer);
 241             Log.d(TAG, "Stopped watching " + localPath);
 242         }
 243
 244     }
 245
 246
 247     /**
 248      *  Private receiver listening to events broadcast by the FileDownloader service.
 249      *
 250      *  Starts and stops the observance on registered files when they are being download,
 251      *  in order to avoid to start unnecessary synchronizations.
 252      */
 253     private class DownloadCompletedReceiverBis extends BroadcastReceiver {
 254
 255         @Override
 256         public void onReceive(Context context, Intent intent) {
 257             String downloadPath = intent.getStringExtra(FileDownloader.EXTRA_FILE_PATH);
 258             OwnCloudFileObserver observer = mObserversMap.get(downloadPath);
 259             if (observer != null) {
 260                 if (intent.getAction().equals(FileDownloader.DOWNLOAD_FINISH_MESSAGE) &&
 261                         new File(downloadPath).exists()) {  // the download could be successful, or not; in both cases, the file could be down, due to a former download or upload
 262                     observer.startWatching();
 263                     Log.d(TAG, "Watching again " + downloadPath);
 264
 265                 } else if (intent.getAction().equals(FileDownloader.DOWNLOAD_ADDED_MESSAGE)) {
 266                     observer.stopWatching();
 267                     Log.d(TAG, "Disabling observance of " + downloadPath);
 268                 }
 269             }
 270         }
 271
 272     }
 273
 274 }