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             if (path == null || path.length() <= 0)
 159                 continue;
 160             OwnCloudFileObserver observer =
 161                     new OwnCloudFileObserver(   path,
 162                                                 account,
 163                                                 getApplicationContext(),
 164                                                 OwnCloudFileObserver.CHANGES_ONLY);
 165             mObserversMap.put(path, observer);
 166             if (new File(path).exists()) {
 167                 observer.startWatching();
 168                 Log.d(TAG, "Started watching file " + path);
 169             }
 170
 171         } while (c.moveToNext());
 172         c.close();
 173     }
 174
 175
 176     /**
 177      * Registers the local copy of a remote file to be observed for local changes,
 178      * an automatically updated in the ownCloud server.
 179      *
 180      * This method does NOT perform a {@link SynchronizeFileOperation} over the file.
 181      *
 182      * TODO We are ignoring that, currently, a local file can be linked to different files
 183      * in ownCloud if it's uploaded several times. That's something pending to update: we
 184      * will avoid that the same local file is linked to different remote files.
 185      *
 186      * @param file      Object representing a remote file which local copy must be observed.
 187      * @param account   OwnCloud account containing file.
 188      */
 189     private void addObservedFile(OCFile file, Account account) {
 190         if (file == null) {
 191             Log.e(TAG, "Trying to add a NULL file to observer");
 192             return;
 193         }
 194         String localPath = file.getStoragePath();
 195         if (localPath == null || localPath.length() <= 0) { // file downloading / to be download for the first time
 196             localPath = FileStorageUtils.getDefaultSavePathFor(account.name, file);
 197         }
 198         OwnCloudFileObserver observer = mObserversMap.get(localPath);
 199         if (observer == null) {
 200             /// the local file was never registered to observe before
 201             observer = new OwnCloudFileObserver(    localPath,
 202                                                     account,
 203                                                     getApplicationContext(),
 204                                                     OwnCloudFileObserver.CHANGES_ONLY);
 205             mObserversMap.put(localPath, observer);
 206             Log.d(TAG, "Observer added for path " + localPath);
 207
 208             if (file.isDown()) {
 209                 observer.startWatching();
 210                 Log.d(TAG, "Started watching " + localPath);
 211             }   // else - the observance can't be started on a file not already down; mDownloadReceiver will get noticed when the download of the file finishes
 212         }
 213
 214     }
 215
 216
 217     /**
 218      * Unregisters the local copy of a remote file to be observed for local changes.
 219      *
 220      * Starts to watch it, if the file has a local copy to watch.
 221      *
 222      * TODO We are ignoring that, currently, a local file can be linked to different files
 223      * in ownCloud if it's uploaded several times. That's something pending to update: we
 224      * will avoid that the same local file is linked to different remote files.
 225      *
 226      * @param file      Object representing a remote file which local copy must be not observed longer.
 227      * @param account   OwnCloud account containing file.
 228      */
 229     private void removeObservedFile(OCFile file, Account account) {
 230         if (file == null) {
 231             Log.e(TAG, "Trying to remove a NULL file");
 232             return;
 233         }
 234         String localPath = file.getStoragePath();
 235         if (localPath == null || localPath.length() <= 0) {
 236             localPath = FileStorageUtils.getDefaultSavePathFor(account.name, file);
 237         }
 238
 239         OwnCloudFileObserver observer = mObserversMap.get(localPath);
 240         if (observer != null) {
 241             observer.stopWatching();
 242             mObserversMap.remove(observer);
 243             Log.d(TAG, "Stopped watching " + localPath);
 244         }
 245
 246     }
 247
 248
 249     /**
 250      *  Private receiver listening to events broadcast by the FileDownloader service.
 251      *
 252      *  Starts and stops the observance on registered files when they are being download,
 253      *  in order to avoid to start unnecessary synchronizations.
 254      */
 255     private class DownloadCompletedReceiverBis extends BroadcastReceiver {
 256
 257         @Override
 258         public void onReceive(Context context, Intent intent) {
 259             String downloadPath = intent.getStringExtra(FileDownloader.EXTRA_FILE_PATH);
 260             OwnCloudFileObserver observer = mObserversMap.get(downloadPath);
 261             if (observer != null) {
 262                 if (intent.getAction().equals(FileDownloader.DOWNLOAD_FINISH_MESSAGE) &&
 263                         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
 264                     observer.startWatching();
 265                     Log.d(TAG, "Watching again " + downloadPath);
 266
 267                 } else if (intent.getAction().equals(FileDownloader.DOWNLOAD_ADDED_MESSAGE)) {
 268                     observer.stopWatching();
 269                     Log.d(TAG, "Disabling observance of " + downloadPath);
 270                 }
 271             }
 272         }
 273
 274     }
 275
 276 }