Bug #252859 --> Add support for dropping RSS urls onto RSS servers and folders to automatically subscribe to the feed.

Bug #252860 --> Add error reporting to alert the user when the feed url could not be downloaded or if the feed url wasn't an rss type we could understand.

sr=bienvenu

mail/extensions/newsblog/content/Feed.js

@@ -14,6 +14,12 @@ var serializer =
     .classes["@mozilla.org/xmlextras/xmlserializer;1"]
       .createInstance(Components.interfaces.nsIDOMSerializer);
 
+// error codes used to inform the consumer about attempts to download a feed
+
+const kNewsBlogSuccess = 0;
+const kNewsBlogInvalidFeed = 1; // usually means there was an error trying to parse the feed...
+const kNewsBlogRequestFailure = 2; // generic networking failure when trying to download the feed.
+
 // Hash of feeds being downloaded, indexed by URL, so the load event listener
 // can access the Feed objects after it finishes downloading the feed files.
 var gFzFeedCache = new Object();
@@ -57,19 +63,27 @@ Feed.prototype.name getter = function() {
 }
 
 Feed.prototype.download = function(parseItems, aCallback) {
+  this.downloadCallback = aCallback; // may be null 
 
   // Whether or not to parse items when downloading and parsing the feed.
   // Defaults to true, but setting to false is useful for obtaining
   // just the title of the feed when the user subscribes to it.
   this.parseItems = parseItems == null ? true : parseItems ? true : false;
 
+  // Before we do anything...make sure the url is an http url. This is just a sanity check
+  // so we don't try opening mailto urls, imap urls, etc. that the user may have tried to subscribe to 
+  // as an rss feed..
+  var uri = Components.classes["@mozilla.org/network/standard-url;1"].
+                      createInstance(Components.interfaces.nsIURI);
+  uri.spec = this.url;
+  if (!uri.schemeIs("http"))
+    return this.onParseError(this); // simulate an invalid feed error
+
   this.request = Components.classes["@mozilla.org/xmlextras/xmlhttprequest;1"]
                  .createInstance(Components.interfaces.nsIXMLHttpRequest);
   this.request.onprogress = Feed.onProgress; // must be set before calling .open
   this.request.open("GET", this.url, true);
 
-  this.downloadCallback = aCallback; // may be null 
-
   this.request.overrideMimeType("text/xml");
   this.request.onload = Feed.onDownloaded;
   this.request.onerror = Feed.onDownloadError;
@@ -100,17 +114,13 @@ Feed.onProgress = function(event) {
 }
 
 Feed.onDownloadError = function(event) {
-  // XXX add error message if available and notify the user?
+  if (feed.downloadCallback)
-  var request = event.target;
+    feed.downloadCallback.downloaded(feed, kNewsBlogRequestFailure);
-  var url = request.channel.originalURI.spec;
+}
-  var feed = gFzFeedCache[url];
+
-  if (feed)
+Feed.prototype.onParseError = function(feed) {
-  {
+  if (feed && feed.downloadCallback)
-    debug(feed.title + " download failed");
+    feed.downloadCallback.downloaded(feed, kNewsBlogInvalidFeed);
-    if (feed.downloadCallback)
-      feed.downloaded(feed, false);
-  }
-  throw("error downloading feed " + url);
 }
 
 Feed.prototype.url getter = function() {
@@ -159,8 +169,7 @@ Feed.prototype.parse = function() {
   debug("parsing feed " + this.url);
 
   if (!this.request.responseText) {
-    throw("error parsing feed " + this.url + ": no data");
+    return this.onParseError(this);
-    return;
   }
   else if (this.request.responseText.search(/="http:\/\/purl\.org\/rss\/1\.0\/"/) != -1) {
     debug(this.url + " is an RSS 1.x (RDF-based) feed");
@@ -192,12 +201,12 @@ Feed.prototype.parse = function() {
 
 Feed.prototype.parseAsRSS2 = function() {
   if (!this.request.responseXML || !(this.request.responseXML instanceof Components.interfaces.nsIDOMXMLDocument))
-    throw("error parsing RSS 2.0 feed " + this.url + ": data not parsed into XMLDocument object");
+    return this.onParseError(this);
 
   // Get the first channel (assuming there is only one per RSS File).
   var channel = this.request.responseXML.getElementsByTagName("channel")[0];
   if (!channel)
-    throw("error parsing RSS 2.0 feed " + this.url + ": channel element missing");
+    return this.onParseError(this);
 
   this.title = this.title || getNodeValue(channel.getElementsByTagName("title")[0]);
   this.description = getNodeValue(channel.getElementsByTagName("description")[0]);
@@ -311,12 +320,12 @@ Feed.prototype.parseAsRSS1 = function() {
 
 Feed.prototype.parseAsAtom = function() {
   if (!this.request.responseXML || !(this.request.responseXML instanceof Components.interfaces.nsIDOMXMLDocument))
-    throw("error parsing Atom feed " + this.url + ": data not parsed into XMLDocument object");
+    return this.onParseError(this);
 
   // Get the first channel (assuming there is only one per Atom File).
   var channel = this.request.responseXML.getElementsByTagName("feed")[0];
   if (!channel)
-    throw("channel missing from Atom feed " + request.channel.name);
+    return this.onParseError(this);
 
   this.title = this.title || getNodeValue(channel.getElementsByTagName("title")[0]);
   this.description = getNodeValue(channel.getElementsByTagName("tagline")[0]);
@@ -443,6 +452,7 @@ Feed.prototype.removeInvalidItems = function() {
 
 var gItemsToStore;
 var gItemsToStoreIndex = 0;
+var gStoreItemsTimer;
 
 // gets the next item from gItemsToStore and forces that item to be stored
 // to the folder. If more items are left to be stored, fires a timer for the next one.
@@ -463,20 +473,16 @@ function storeNextItem()
 
   if (gItemsToStoreIndex < gItemsToStore.length)
   {
-    if ('setTimeout' in this)
+    if (!gStoreItemsTimer)
-      setTimeout(storeNextItem, 50); // fire off a timer for the next item to store
+      gStoreItemsTimer = Components.classes["@mozilla.org/timer;1"].createInstance(Components.interfaces.nsITimer);
-    else
+    gStoreItemsTimer.initWithCallback(storeNextItemTimerCallback, 50, Components.interfaces.nsITimer.TYPE_ONE_SHOT);
-    {
-      debug('set timeout is not defined if this call originated from newsblog.js\n');
-      storeNextItem();
-    }
   }
   else
   {    
     item.feed.removeInvalidItems();
 
     if (item.feed.downloadCallback)
-      item.feed.downloadCallback.downloaded(item.feed, true);
+      item.feed.downloadCallback.downloaded(item.feed, kNewsBlogSuccess);
 
     item.feed.request = null; // force the xml http request to go away. This helps reduce some
                               // nasty assertions on shut down of all things.
@@ -485,3 +491,17 @@ function storeNextItem()
     gItemsToStoreIndex = 0;
   }   
 }
+
+var storeNextItemTimerCallback = {
+  notify: function(aTimer) {
+    storeNextItem();
+  },
+  
+  QueryInterface: function(aIID) {
+    if (aIID.equals(Components.interfaces.nsITimerCallback) || aIID.equals(Components.interfaces.nsISupports))
+      return this;
+    
+    Components.returnCode = Components.results.NS_ERROR_NO_INTERFACE;
+    return null;           
+  }
+}

mail/extensions/newsblog/content/subscriptions.js

@@ -34,7 +34,6 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
-var kFeedUrlDelimiter = '|'; // the delimiter used to delimit feed urls in the msg folder database "feedUrl" property
 var gRSSServer = null;
 
 function doLoad() {
@@ -74,10 +73,10 @@ function clearStatusInfo()
 }
 
 var feedDownloadCallback = {
-  downloaded: function(feed, aSuccess)
+  downloaded: function(feed, aErrorCode)
   {
     // feed is null if our attempt to parse the feed failed
-    if (aSuccess)
+    if (aErrorCode == kNewsBlogSuccess)
     {
       updateStatusItem('progressMeter', 100);
 
@@ -91,10 +90,10 @@ var feedDownloadCallback = {
       // it also flushes the subscription datasource
       addFeed(feed.url, feed.name, null, folder); 
     } 
-    else 
+    else if (aErrorCode == kNewsBlogInvalidFeed) //  the feed was bad...
-    {
+      window.alert(document.getElementById('bundle_newsblog').getFormattedString('newsblog-invalidFeed', [feed.url]));
-      // Add some code to alert the user that the feed was not something we could understand...  
+    else // we never even downloaded the feed...(kNewsBlogRequestFailure)
-    }
+      window.alert(document.getElementById('bundle_newsblog').getFormattedString('newsblog-networkError', [feed.url]));
 
     // our operation is done...clear out the status text and progressmeter
     setTimeout(clearStatusInfo, 1000);
@@ -116,23 +115,6 @@ var feedDownloadCallback = {
   },
 }
 
-// updates the "feedUrl" property in the message database for the folder in question.
-function updateFolderFeedUrl(aFolder, aFeedUrl, aRemoveUrl)
-{
-  var msgdb = aFolder.QueryInterface(Components.interfaces.nsIMsgFolder).getMsgDatabase(null);
-  var folderInfo = msgdb.dBFolderInfo;
-  var oldFeedUrl = folderInfo.getCharPtrProperty("feedUrl");
-
-  if (aRemoveUrl)
-  { 
-    // remove our feed url string from the list of feed urls
-    var newFeedUrl = oldFeedUrl.replace(kFeedUrlDelimiter + aFeedUrl, "");
-    folderInfo.setCharPtrProperty("feedUrl", newFeedUrl);
-  }  
-  else 
-    folderInfo.setCharPtrProperty("feedUrl", oldFeedUrl + kFeedUrlDelimiter + aFeedUrl);  
-}
-
 function doAdd() {
     var userAddedFeed = false; 
     var feedProperties = { feedName: "", feedLocation: "", serverURI: gRSSServer.serverURI, folderURI: "", result: userAddedFeed};

mail/extensions/newsblog/content/utils.js

@@ -88,6 +88,25 @@ function addFeed(url, title, quickMode, destFolder) {
     ds.Flush();
 }
 
+// updates the "feedUrl" property in the message database for the folder in question.
+
+var kFeedUrlDelimiter = '|'; // the delimiter used to delimit feed urls in the msg folder database "feedUrl" property
+
+function updateFolderFeedUrl(aFolder, aFeedUrl, aRemoveUrl)
+{
+  var msgdb = aFolder.QueryInterface(Components.interfaces.nsIMsgFolder).getMsgDatabase(null);
+  var folderInfo = msgdb.dBFolderInfo;
+  var oldFeedUrl = folderInfo.getCharPtrProperty("feedUrl");
+
+  if (aRemoveUrl)
+  { 
+    // remove our feed url string from the list of feed urls
+    var newFeedUrl = oldFeedUrl.replace(kFeedUrlDelimiter + aFeedUrl, "");
+    folderInfo.setCharPtrProperty("feedUrl", newFeedUrl);
+  }  
+  else 
+    folderInfo.setCharPtrProperty("feedUrl", oldFeedUrl + kFeedUrlDelimiter + aFeedUrl);  
+}
 
 function getNodeValue(node) {
   if (node && node.textContent)

mail/extensions/newsblog/js/newsblog.js

@@ -51,7 +51,7 @@ var nsNewsBlogFeedDownloader =
     var rdf = Components.classes["@mozilla.org/rdf/rdf-service;1"]
         .getService(Components.interfaces.nsIRDFService);
 
-    progressNotifier.init(aMsgWindow.statusFeedback);
+    progressNotifier.init(aMsgWindow.statusFeedback, false);
     
     var index = 0; 
     for (url in feedUrlArray)
@@ -68,6 +68,23 @@ var nsNewsBlogFeedDownloader =
     }
   },
 
+  subscribeToFeed: function(aUrl, aFolder, aMsgWindow)
+  {
+    if (!gExternalScriptsLoaded)
+      loadScripts();
+    var rdf = Components.classes["@mozilla.org/rdf/rdf-service;1"]
+              .getService(Components.interfaces.nsIRDFService);
+    
+    var itemResource = rdf.GetResource(aUrl);
+    var feed = new Feed(itemResource);
+    feed.server = aFolder.server;
+    if (!aFolder.server.isServer) // if the root server, create a new folder for the feed
+      feed.folder = aFolder; // user must want us to add this subscription url to an existing RSS folder.
+
+    progressNotifier.init(aMsgWindow.statusFeedback, true);
+    feed.download(true, progressNotifier);
+  },
+
   QueryInterface: function(aIID)
   {
     if (aIID.equals(Components.interfaces.nsINewsBlogFeedDownloader) ||
@@ -222,33 +239,52 @@ function loadScripts()
 var gNumPendingFeedDownloads = 0;
 
 var progressNotifier = {
-
+  mSubscribeMode: false, 
   mStatusFeedback: null,
   mFeeds: new Array,
 
-  init: function(aStatusFeedback)
+  init: function(aStatusFeedback, aSubscribeMode)
   {
     if (!gNumPendingFeedDownloads) // if we aren't already in the middle of downloading feed items...
     {
       this.mStatusFeedback = aStatusFeedback;
+      this.mSubscribeMode = aSubscribeMode;
       this.mStatusFeedback.startMeteors();
-      this.mStatusFeedback.showStatusString(GetString('newsblog-getNewMailCheck'));
+
+      this.mStatusFeedback.showStatusString(aSubscribeMode ? GetNewsBlogStringBundle().GetStringFromName('subscribe-validating') 
+                                            : GetNewsBlogStringBundle().GetStringFromName('newsblog-getNewMailCheck'));
     }
   },
 
-  downloaded: function(feed)
+  downloaded: function(feed, aErrorCode)
   {
+    if (this.mSubscribeMode && aErrorCode == kNewsBlogSuccess)
+    {
+      // if we get here...we should always have a folder by now...either
+      // in feed.folder or FeedItems created the folder for us....
+      var folder = feed.folder ? feed.folder : feed.server.rootMsgFolder.getChildNamed(feed.name);
+      updateFolderFeedUrl(folder, feed.url, false);        
+      addFeed(feed.url, feed.name, null, folder); // add feed just adds the feed to the subscription UI and flushes the datasource
+    } 
+    else if (aErrorCode == kNewsBlogInvalidFeed)
+      this.mStatusFeedback.showStatusString(GetNewsBlogStringBundle().formatStringFromName("newsblog-invalidFeed",
+                                            [feed.url], 1));
+    else if (aErrorCode == kNewsBlogRequestFailure)
+      this.mStatusFeedback.showStatusString(GetNewsBlogStringBundle().formatStringFromName("newsblog-networkError",
+                                            [feed.url], 1));
+      
     this.mStatusFeedback.stopMeteors();
     gNumPendingFeedDownloads--;
     if (!gNumPendingFeedDownloads)
     {
       this.mFeeds = new Array;
 
-      // no more pending actions...clear the status bar text...should we do this on a timer
+      this.mSubscribeMode = false;
-      // so the text sticks around for a little while? It doesnt look like we do it on a timer for 
-      // newsgroups so we'll follow that model.
 
-      this.mStatusFeedback.showStatusString("");
+      // should we do this on a timer so the text sticks around for a little while? 
+      // It doesnt look like we do it on a timer for newsgroups so we'll follow that model.
+      if (aErrorCode == kNewsBlogSuccess) // don't clear the status text if we just dumped an error to the status bar!
+        this.mStatusFeedback.showStatusString("");
     }
   },
 
@@ -259,6 +295,12 @@ var progressNotifier = {
   { 
     // we currently don't do anything here. Eventually we may add
     // status text about the number of new feed articles received.
+
+    if (this.mSubscribeMode) // if we are subscribing to a feed, show feed download progress
+    {
+      this.mStatusFeedback.showStatusString(GetNewsBlogStringBundle().formatStringFromName("subscribe-fetchingFeedItems", [aCurrentFeedItems, aMaxFeedItems], 2));
+      this.onProgress(feed, aCurrentFeedItems, aMaxFeedItems);
+    }
   },
 
   onProgress: function(feed, aProgress, aProgressMax)
@@ -292,10 +334,10 @@ var progressNotifier = {
   }
 }
 
-function GetString(name)
+function GetNewsBlogStringBundle(name)
 {
   var strBundleService = Components.classes["@mozilla.org/intl/stringbundle;1"].getService(); 
   strBundleService = strBundleService.QueryInterface(Components.interfaces.nsIStringBundleService);
   var strBundle = strBundleService.createBundle("chrome://messenger-newsblog/locale/newsblog.properties"); 
-  return strBundle.GetStringFromName(name);
+  return strBundle;
 }

mail/extensions/newsblog/locale/newsblog.properties

@@ -1,6 +1,6 @@
 # Status strings used in the subscribe dialog
 
-subscribe-validating=Verifying the feed...
+subscribe-validating=Verifying the RSS feed...
 
 # when downloading new feed items from the subscribe dialog. 
 # LOCALIZATION NOTE: Do not translate %d in the following line.
@@ -8,4 +8,6 @@ subscribe-validating=Verifying the feed...
 # the second %S will receive the total number of messages
 subscribe-fetchingFeedItems=Downloading feed articles (%S of %S)
 
+newsblog-invalidFeed=%S is not a valid RSS feed.
+newsblog-networkError=%S could not be found. Please check the name and try again.
 newsblog-getNewMailCheck=Checking RSS feeds for new items

mailnews/base/resources/content/messengerdnd.js

@@ -69,6 +69,7 @@ function CanDropOnFolderTree(index, orientation)
 
     trans.addDataFlavor("text/x-moz-message");
     trans.addDataFlavor("text/x-moz-folder");
+    trans.addDataFlavor("text/x-moz-url");
  
     var folderTree = GetFolderTree();
     var targetResource = GetFolderResource(folderTree, index);
@@ -121,33 +122,43 @@ function CanDropOnFolderTree(index, orientation)
             if (hdr.folder == targetFolder)
                 return false;
             break;
+        } else if (dataFlavor.value == "text/x-moz-folder") {
+
+          // we should only get here if we are dragging and dropping folders
+          dragFolder = true;
+          sourceResource = RDF.GetResource(sourceUri);
+          var sourceFolder = sourceResource.QueryInterface(Components.interfaces.nsIMsgFolder);
+          sourceServer = sourceFolder.server;
+
+          if (targetUri == sourceUri)	
+              return false;
+
+          //don't allow drop on different imap servers.
+          if (sourceServer != targetServer && targetServer.type == "imap")
+              return false;
+
+          //don't allow immediate child to be dropped to it's parent
+          if (targetFolder.URI == sourceFolder.parent.URI)
+          {
+              debugDump(targetFolder.URI + "\n");
+              debugDump(sourceFolder.parent.URI + "\n");     
+              return false;
+          }
+
+          var isAncestor = sourceFolder.isAncestorOf(targetFolder);
+          // don't allow parent to be dropped on its ancestors
+          if (isAncestor)
+              return false;
+        } else if (dataFlavor.value == "text/x-moz-url") {
+          // eventually check to make sure this is an http url before doing anything else...
+          var uri = Components.classes["@mozilla.org/network/standard-url;1"].
+                      createInstance(Components.interfaces.nsIURI);
+          var url = sourceUri.split("\n")[0];
+          uri.spec = url;
+
+          if (uri.schemeIs("http") && targetServer && targetServer.type == 'rss')
+            return true;
         }
-
-        // we should only get here if we are dragging and dropping folders
-        dragFolder = true;
-        sourceResource = RDF.GetResource(sourceUri);
-        var sourceFolder = sourceResource.QueryInterface(Components.interfaces.nsIMsgFolder);
-        sourceServer = sourceFolder.server;
-
-        if (targetUri == sourceUri)	
-            return false;
-
-        //don't allow drop on different imap servers.
-        if (sourceServer != targetServer && targetServer.type == "imap")
-            return false;
-
-        //don't allow immediate child to be dropped to it's parent
-        if (targetFolder.URI == sourceFolder.parent.URI)
-        {
-            debugDump(targetFolder.URI + "\n");
-            debugDump(sourceFolder.parent.URI + "\n");     
-            return false;
-        }
-
-        var isAncestor = sourceFolder.isAncestorOf(targetFolder);
-        // don't allow parent to be dropped on its ancestors
-        if (isAncestor)
-            return false;
     }
 
     if (dragFolder)
@@ -198,6 +209,8 @@ function DropOnFolderTree(row, orientation)
 
     var folderTree = GetFolderTree();
     var targetResource = GetFolderResource(folderTree, row);
+    var targetFolder = targetResource.QueryInterface(Components.interfaces.nsIMsgFolder);
+    var targetServer = targetFolder.server;
 
     var targetUri = targetResource.Value;
     debugDump("***targetUri = " + targetUri + "\n");
@@ -209,6 +222,7 @@ function DropOnFolderTree(row, orientation)
     var trans = Components.classes["@mozilla.org/widget/transferable;1"].createInstance(Components.interfaces.nsITransferable);
     trans.addDataFlavor("text/x-moz-message");
     trans.addDataFlavor("text/x-moz-folder");
+    trans.addDataFlavor("text/x-moz-url");
 
     var list = Components.classes["@mozilla.org/supports-array;1"].createInstance(Components.interfaces.nsISupportsArray);
 
@@ -248,6 +262,24 @@ function DropOnFolderTree(row, orientation)
           }
           else if (flavor.value == "text/x-moz-message")
             dropMessage = true;
+          else if (flavor.value == "text/x-moz-url")
+          {
+            var uri = Components.classes["@mozilla.org/network/standard-url;1"].
+                        createInstance(Components.interfaces.nsIURI);
+            var url = sourceUri.split("\n")[0];
+            uri.spec = url;
+            
+            if (uri.schemeIs("http") && targetServer && targetServer.type == 'rss')
+            {
+              var rssService = Components.classes["@mozilla.org/newsblog-feed-downloader;1"].getService().
+                               QueryInterface(Components.interfaces.nsINewsBlogFeedDownloader);
+              if (rssService)
+                rssService.subscribeToFeed(url, targetFolder, msgWindow);
+              return true;
+            }
+            else 
+              return false;            
+          }
         }
         else {
            if (!dropMessage)
@@ -273,9 +305,6 @@ function DropOnFolderTree(row, orientation)
 
     var isSourceNews = false;
     isSourceNews = isNewsURI(sourceUri);
-    
-    var targetFolder = targetResource.QueryInterface(Components.interfaces.nsIMsgFolder);
-    var targetServer = targetFolder.server;
 
     if (dropMessage) {
         var sourceMsgHdr = list.GetElementAt(0).QueryInterface(Components.interfaces.nsIMsgDBHdr);

mailnews/local/public/nsINewsBlogFeedDownloader.idl

@@ -46,5 +46,9 @@ interface nsINewsBlogFeedDownloader : nsISupports
   void downloadFeed(in string aUrl, in nsIMsgFolder aFolder,
                      in boolean aQuickMode, in wstring aTitle,  
 					in nsIUrlListener aUrlListener, in nsIMsgWindow aMsgWindow);
+
+  /* A convient method to subscribe to feeds without going through the subscribe UI
+     used by drag and drop */
+  void subscribeToFeed(in string aUrl, in nsIMsgFolder aFolder, in nsIMsgWindow aMsgWindow);
 };