Modify OwncloudFileObserver for enforcing watching the file when an external app cancelled the watch and added a handler for startWatching again

src/com/owncloud/android/files/OwnCloudFileObserver.java

@@ -20,92 +20,129 @@ package com.owncloud.android.files;
 
 import java.io.File;
 
+import android.accounts.Account;
+import android.content.Context;
+import android.content.Intent;
+import android.os.FileObserver;
+import android.os.Handler;
+
 import com.owncloud.android.datamodel.FileDataStorageManager;
 import com.owncloud.android.datamodel.OCFile;
 import com.owncloud.android.lib.common.operations.RemoteOperationResult;
-import com.owncloud.android.operations.SynchronizeFileOperation;
 import com.owncloud.android.lib.common.operations.RemoteOperationResult.ResultCode;
+import com.owncloud.android.operations.SynchronizeFileOperation;
 import com.owncloud.android.ui.activity.ConflictsResolveActivity;
 import com.owncloud.android.utils.Log_OC;
 
-import android.accounts.Account;
-import android.content.Context;
-import android.content.Intent;
-import android.os.FileObserver;
-
 public class OwnCloudFileObserver extends FileObserver {
 
     private static int MASK = (FileObserver.MODIFY | FileObserver.CLOSE_WRITE);
-    
+    private static int IN_IGNORE = 32768;
+
     private static String TAG = OwnCloudFileObserver.class.getSimpleName();
-    
+
     private String mPath;
     private int mMask;
     private Account mOCAccount;
     private Context mContext;
     private boolean mModified;
+    private long mFileLastModified;
+    private boolean mRestartWatching;
+    private Handler mHandler;
 
-    
-    public OwnCloudFileObserver(String path, Account account, Context context) {
-        super(path, MASK);
+    public OwnCloudFileObserver(String path, Account account, Context context, Handler handler) {
+        super(path, FileObserver.ALL_EVENTS);
         if (path == null)
-            throw new IllegalArgumentException("NULL path argument received"); 
+            throw new IllegalArgumentException("NULL path argument received");
         if (account == null)
-            throw new IllegalArgumentException("NULL account argument received"); 
+            throw new IllegalArgumentException("NULL account argument received");
         if (context == null)
             throw new IllegalArgumentException("NULL context argument received");
         mPath = path;
         mOCAccount = account;
-        mContext = context; 
+        mContext = context;
         mModified = false;
+        mFileLastModified = new File(path).lastModified();
+        mHandler = handler;
+        Log_OC.d(TAG, "Create Observer - FileLastModified: " + mFileLastModified);
     }
-    
-    
+
     @Override
     public void onEvent(int event, String path) {
-        Log_OC.d(TAG, "Got file modified with event " + event + " and path " + mPath + ((path != null) ? File.separator + path : ""));
+        Log_OC.d(TAG, "Got file modified with event " + event + " and path " + mPath
+                + ((path != null) ? File.separator + path : ""));
         if ((event & MASK) == 0) {
-            Log_OC.wtf(TAG, "Incorrect event " + event + " sent for file " + mPath + ((path != null) ? File.separator + path : "") +
-                         " with registered for " + mMask + " and original path " +
-                         mPath);
+            Log_OC.wtf(TAG, "Incorrect event " + event + " sent for file " + mPath
+                    + ((path != null) ? File.separator + path : "") + " with registered for " + mMask
+                    + " and original path " + mPath);
+
+            // in case need start watching again
+            if ((event & IN_IGNORE) != 0 && mRestartWatching) {
+                mRestartWatching = false;
+
+                mHandler.postDelayed(new Runnable() {
+                    public void run() {
+                        startWatching();
+                    }
+                }, 5000);
+
+            }
         } else {
             if ((event & FileObserver.MODIFY) != 0) {
                 // file changed
                 mModified = true;
             }
-            // not sure if it's possible, but let's assume that both kind of events can be received at the same time
+            // not sure if it's possible, but let's assume that both kind of
+            // events can be received at the same time
             if ((event & FileObserver.CLOSE_WRITE) != 0) {
                 // file closed
                 if (mModified) {
                     mModified = false;
+                    mRestartWatching = false;
+                    startSyncOperation();
+                } else if (isFileUpdated()) {
+                    // if file has been modified but Modify event type has not
+                    // been launched
+                    mRestartWatching = true;
+                    mFileLastModified = new File(mPath).lastModified();
+                    Log_OC.d(TAG, "CLOSE_WRITE - New FileLastModified: " + mFileLastModified);
                     startSyncOperation();
                 }
             }
-        }  
+        }
     }
 
-    
     private void startSyncOperation() {
         FileDataStorageManager storageManager = new FileDataStorageManager(mOCAccount, mContext.getContentResolver());
-        OCFile file = storageManager.getFileByLocalPath(mPath);     // a fresh object is needed; many things could have occurred to the file since it was registered to observe
-                                                                    // again, assuming that local files are linked to a remote file AT MOST, SOMETHING TO BE DONE; 
-        SynchronizeFileOperation sfo = new SynchronizeFileOperation(file, 
-                                                                    null, 
-                                                                    mOCAccount, 
-                                                                    true, 
-                                                                    mContext);
+        // a fresh object is needed; many things could have occurred to the file
+        // since it was registered to observe again, assuming that local files
+        // are linked to a remote file AT MOST, SOMETHING TO BE DONE;
+        OCFile file = storageManager.getFileByLocalPath(mPath);
+        SynchronizeFileOperation sfo = new SynchronizeFileOperation(file, null, mOCAccount, true, mContext);
         RemoteOperationResult result = sfo.execute(storageManager, mContext);
         if (result.getCode() == ResultCode.SYNC_CONFLICT) {
-            // ISSUE 5: if the user is not running the app (this is a service!), this can be very intrusive; a notification should be preferred
+            // ISSUE 5: if the user is not running the app (this is a service!),
+            // this can be very intrusive; a notification should be preferred
             Intent i = new Intent(mContext, ConflictsResolveActivity.class);
             i.setFlags(i.getFlags() | Intent.FLAG_ACTIVITY_NEW_TASK);
             i.putExtra(ConflictsResolveActivity.EXTRA_FILE, file);
             i.putExtra(ConflictsResolveActivity.EXTRA_ACCOUNT, mOCAccount);
             mContext.startActivity(i);
         }
-        // TODO save other errors in some point where the user can inspect them later;
-        //      or maybe just toast them;
-        //      or nothing, very strange fails
+        // TODO save other errors in some point where the user can inspect them
+        // later;
+        // or maybe just toast them;
+        // or nothing, very strange fails
+    }
+
+    /**
+     * Check if the timestamp of last file modification in local is more current
+     * that the timestamp when setting observer to the file
+     * 
+     * @return boolean: True if file is updated, False if not
+     */
+    private boolean isFileUpdated() {
+        Log_OC.d(TAG, "FileLastModified: " + mFileLastModified);
+        return (new File(mPath).lastModified() > mFileLastModified);
     }
-    
 }

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

@@ -22,16 +22,6 @@ import java.io.File;
 import java.util.HashMap;
 import java.util.Map;
 
-import com.owncloud.android.MainApp;
-import com.owncloud.android.datamodel.FileDataStorageManager;
-import com.owncloud.android.datamodel.OCFile;
-import com.owncloud.android.db.ProviderMeta.ProviderTableMeta;
-import com.owncloud.android.files.OwnCloudFileObserver;
-import com.owncloud.android.operations.SynchronizeFileOperation;
-import com.owncloud.android.utils.FileStorageUtils;
-import com.owncloud.android.utils.Log_OC;
-
-
 import android.accounts.Account;
 import android.accounts.AccountManager;
 import android.app.Service;
@@ -41,8 +31,18 @@ import android.content.Intent;
 import android.content.IntentFilter;
 import android.database.Cursor;
 import android.os.Binder;
+import android.os.Handler;
 import android.os.IBinder;
 
+import com.owncloud.android.MainApp;
+import com.owncloud.android.datamodel.FileDataStorageManager;
+import com.owncloud.android.datamodel.OCFile;
+import com.owncloud.android.db.ProviderMeta.ProviderTableMeta;
+import com.owncloud.android.files.OwnCloudFileObserver;
+import com.owncloud.android.operations.SynchronizeFileOperation;
+import com.owncloud.android.utils.FileStorageUtils;
+import com.owncloud.android.utils.Log_OC;
+
 public class FileObserverService extends Service {
 
     public final static int CMD_INIT_OBSERVED_LIST = 1;
@@ -58,6 +58,7 @@ public class FileObserverService extends Service {
     private static Map<String, OwnCloudFileObserver> mObserversMap;
     private static DownloadCompletedReceiverBis mDownloadReceiver;
     private IBinder mBinder = new LocalBinder();
+    private Handler mHandler = new Handler();
     
     public class LocalBinder extends Binder {
         FileObserverService getService() {
@@ -160,10 +161,7 @@ public class FileObserverService extends Service {
             String path = c.getString(c.getColumnIndex(ProviderTableMeta.FILE_STORAGE_PATH));
             if (path == null || path.length() <= 0)
                 continue;
-            OwnCloudFileObserver observer =
-                    new OwnCloudFileObserver(   path, 
-                                                account, 
-                                                getApplicationContext());
+            OwnCloudFileObserver observer = new OwnCloudFileObserver(path, account, getApplicationContext(), mHandler);
             mObserversMap.put(path, observer);
             if (new File(path).exists()) {
                 observer.startWatching();
@@ -202,7 +200,8 @@ public class FileObserverService extends Service {
             /// the local file was never registered to observe before
             observer = new OwnCloudFileObserver(    localPath, 
                                                     account, 
-                                                    getApplicationContext());
+                                                    getApplicationContext(),
+                                                    mHandler);
             mObserversMap.put(localPath, observer);
             Log_OC.d(TAG, "Observer added for path " + localPath);