src/com/owncloud/android/operations/ExistenceCheckOperation.java

   1 /* ownCloud Android client application
   2  *   Copyright (C) 2012 ownCloud Inc.
   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.operations;
  20
  21 import org.apache.commons.httpclient.HttpStatus;
  22 import org.apache.commons.httpclient.methods.HeadMethod;
  23
  24 import eu.alefzero.webdav.WebdavClient;
  25 import android.content.Context;
  26 import android.net.ConnectivityManager;
  27 import android.util.Log;
  28
  29 /**
  30  * Operation to check the existence or absence of a path in a remote server.
  31  *
  32  * @author David A. Velasco
  33  */
  34 public class ExistenceCheckOperation extends RemoteOperation {
  35
  36     /** Maximum time to wait for a response from the server in MILLISECONDs.  */
  37     public static final int TIMEOUT = 10000;
  38
  39     private static final String TAG = ExistenceCheckOperation.class.getSimpleName();
  40
  41     private String mPath;
  42     private Context mContext;
  43     private boolean mSuccessIfAbsent;
  44     private String mAccessToken;
  45
  46
  47     /**
  48      * Simple constructor. Success when the path in the server exists.
  49      *
  50      * @param path          Path to append to the URL owned by the client instance.
  51      * @param context       Android application context.
  52      * @param accessToken   Access token for Bearer Authentication -> TODO: move to other place
  53      */
  54     public ExistenceCheckOperation(String path, Context context, String accessToken) {
  55         this(path, context, false);
  56         mAccessToken = accessToken;
  57     }
  58
  59
  60     /**
  61      * Full constructor. Success of the operation will depend upon the value of successIfAbsent.
  62      *
  63      * @param path              Path to append to the URL owned by the client instance.
  64      * @param context           Android application context.
  65      * @param successIfAbsent   When 'true', the operation finishes in success if the path does NOT exist in the remote server (HTTP 404).
  66      */
  67     public ExistenceCheckOperation(String path, Context context, boolean successIfAbsent) {
  68         mPath = (path != null) ? path : "";
  69         mContext = context;
  70         mSuccessIfAbsent = successIfAbsent;
  71     }
  72
  73
  74         @Override
  75         protected RemoteOperationResult run(WebdavClient client) {
  76         if (!isOnline()) {
  77             return new RemoteOperationResult(RemoteOperationResult.ResultCode.NO_NETWORK_CONNECTION);
  78         }
  79         RemoteOperationResult result = null;
  80         HeadMethod head = null;
  81         try {
  82             head = new HeadMethod(client.getBaseUri() + mPath);
  83             head.addRequestHeader("Authorization", "Bearer " + mAccessToken);   // TODO put in some general place
  84
  85             int status = client.executeMethod(head, TIMEOUT, TIMEOUT);
  86             client.exhaustResponse(head.getResponseBodyAsStream());
  87             boolean success = (status == HttpStatus.SC_OK && !mSuccessIfAbsent) || (status == HttpStatus.SC_NOT_FOUND && mSuccessIfAbsent);
  88             result = new RemoteOperationResult(success, status);
  89             Log.d(TAG, "Existence check for " + client.getBaseUri() + mPath + " targeting for " + (mSuccessIfAbsent ? " absence " : " existence ") + "finished with HTTP status " + status + (!success?"(FAIL)":""));
  90
  91         } catch (Exception e) {
  92             result = new RemoteOperationResult(e);
  93             Log.e(TAG, "Existence check for " + client.getBaseUri() + mPath + " targeting for " + (mSuccessIfAbsent ? " absence " : " existence ") + ": " + result.getLogMessage(), result.getException());
  94
  95         } finally {
  96             if (head != null)
  97                 head.releaseConnection();
  98         }
  99         return result;
 100         }
 101
 102     private boolean isOnline() {
 103         ConnectivityManager cm = (ConnectivityManager) mContext
 104                 .getSystemService(Context.CONNECTIVITY_SERVICE);
 105         return cm != null && cm.getActiveNetworkInfo() != null
 106                 && cm.getActiveNetworkInfo().isConnectedOrConnecting();
 107     }
 108
 109 }