Reading binary files.

Support for reading binary files and some cleanup regarding the move
from manual callbacks to promises.

tests/tests.js

@@ -517,5 +517,22 @@ define(['jquery', 'title', 'archive', 'zimArchive', 'zimDirEntry', 'util', 'geom
                 });
             });
         });
+        asyncTest("Image 'I/m/RayCharles_AManAndHisSoul.jpg' can be loaded", function() {
+            expect(6);
+            localZimArchive.getTitleByName("(The_Night_Time_Is)_The_Right_Time.html", function(title) {
+                console.log(title);
+                ok(title !== null, "Title found");
+                ok(title.isRedirect(), "Title is a redirect.");
+                localZimArchive.resolveRedirect(title, function(title) {
+                    ok(title !== null, "Title found");
+                    ok(!title.isRedirect(), "Title is not a redirect.");
+                    localZimArchive.readBinaryFile(title, function(title, data) {
+                        ok(data.length === 58666, "Data length is correct.");
+                        ok(data[361] === 121, "Data is correct at some point.");
+                        start();
+                    });
+                });
+            });
+        });
     };
 });

www/js/app.js

@@ -768,24 +768,23 @@ define(['jquery', 'abstractBackend', 'util', 'cookies','geometry','osabstraction
                 console.log("we are asked for a content : let's try to answer to this message");
                 var titleName = event.data.titleName;
                 var messagePort = event.ports[0];
-                selectedArchive.getTitleByName(titleName, function(title) {
+                var readFile = function(title) {
-                    // TODO handle other content types
+                    console.log("Found title.");
-                    // TODO a Promise would avoid duplicating the code here
-                    // Cf https://github.com/mossroy/evopedia-html5/issues/67
                     if (title.isRedirect()) {
-                        selectedArchive.resolveRedirect(title, function(title) {
+                        console.log("Following redirect...");
-                            selectedArchive.readArticle(title, function(readableTitleName, content) {
+                        selectedArchive.resolveRedirect(title, readFile);
+                    } else {
+                        console.log("Reading binary file...");
+                        selectedArchive.readBinaryFile(title, function(readableTitleName, content) {
                             messagePort.postMessage({'action': 'giveContent', 'titleName' : titleName, 'content': content});
-                                console.log("content sent to ServiceWorker (after a redirect)");
+                            console.log("content sent to ServiceWorker)");
-                            });
                         });
                     }
-                    else {
-                        selectedArchive.readArticle(title, function(readableTitleName, content) {
-                            messagePort.postMessage({'action': 'giveContent', 'titleName' : titleName, 'content': content});
-                            console.log("content sent to ServiceWorker");
-                        });
                 }
+                console.log("Fetching tile " + titleName);
+                selectedArchive.getTitleByName(titleName).then(readFile).fail(function() {
+                    console.log("could not find title:" + arguments);
+                    messagePort.postMessage({'action': 'giveContent', 'titleName' : titleName, 'content': new UInt8Array()});
                 });
             }
             else {
@@ -966,7 +965,7 @@ define(['jquery', 'abstractBackend', 'util', 'cookies','geometry','osabstraction
      * @param {String} titleName
      */
     function goToArticle(titleName) {
-        selectedArchive.getTitleByName(titleName, function(title) {
+        selectedArchive.getTitleByName(titleName).then(function(title) {
             if (title === null || title === undefined) {
                 $("#readingArticle").hide();
                 alert("Article with title " + titleName + " not found in the archive");
@@ -977,7 +976,7 @@ define(['jquery', 'abstractBackend', 'util', 'cookies','geometry','osabstraction
                 $('#articleContent').contents().find('body').html("");
                 readArticle(title);
             }
-        });
+        }).fail(function() { alert("Error reading title " + titleName); });
     }
        
     /**

www/js/lib/archive.js

@@ -332,23 +332,17 @@ define(['normalize_string', 'geometry', 'title', 'util', 'titleIterators', 'q'],
         }).then(callbackFunction, errorHandler);
     };
     
-    /**
-     * @callback callbackTitle
-     * @param {Title} title Title found
-     */
-
     /**
      * Look for a title by its name, and call the callbackFunction with this Title
      * If the title is not found, the callbackFunction is called with parameter null
      * @param {String} titleName
-     * @param {callbackTitle} callbackFunction
      */
-    LocalArchive.prototype.getTitleByName = function(titleName, callbackFunction) {
+    LocalArchive.prototype.getTitleByName = function(titleName) {
         var that = this;
         var normalize = this.getNormalizeFunction();
         var normalizedTitleName = normalize(titleName);
 
-        titleIterators.findPrefixOffset(this._titleFile, titleName, normalize).then(function(offset) {
+        return titleIterators.findPrefixOffset(this._titleFile, titleName, normalize).then(function(offset) {
             var iterator = new titleIterators.SequentialTitleIterator(that, offset);
             function check(title) {
                 if (title === null || normalize(title._name) !== normalizedTitleName) {
@@ -360,7 +354,7 @@ define(['normalize_string', 'geometry', 'title', 'util', 'titleIterators', 'q'],
                 }
             }
             return iterator.advance().then(check);
-        }).then(callbackFunction, errorHandler);
+        });
     };
 
     /**

www/js/lib/zimArchive.js

@@ -20,8 +20,8 @@
  * along with Evopedia (file LICENSE-GPLv3.txt).  If not, see <http://www.gnu.org/licenses/>
  */
 'use strict';
-define(['zimfile', 'zimDirEntry', 'util'],
+define(['zimfile', 'zimDirEntry', 'util', 'utf8'],
-    function(zimfile, zimDirEntry, util) {
+    function(zimfile, zimDirEntry, util, utf8) {
     
     /**
      * ZIM Archive
@@ -176,6 +176,22 @@ define(['zimfile', 'zimDirEntry', 'util'],
      * @param {callbackStringContent} callback
      */
     ZIMArchive.prototype.readArticle = function(title, callback) {
+        return title.readData().then(function(data) {
+            callback(title.name(), utf8.parse(data));
+        });
+    };
+
+    /**
+     * @callback callbackBinaryContent
+     * @param {Uint8Array} content binary content
+     */
+
+    /**
+     * Read a binary file.
+     * @param {DirEntry} title
+     * @param {callbackBinaryContent} callback
+     */
+    ZIMArchive.prototype.readBinaryFile = function(title, callback) {
         return title.readData().then(function(data) {
             callback(title.name(), data);
         });
@@ -184,11 +200,10 @@ define(['zimfile', 'zimDirEntry', 'util'],
     /**
      * 
      * @param {String} titleName
-     * @param {callbackTitle} callback
      */
-    ZIMArchive.prototype.getTitleByName = function(titleName, callback) {
+    ZIMArchive.prototype.getTitleByName = function(titleName) {
         var that = this;
-        util.binarySearch(0, this._file.articleCount, function(i) {
+        return util.binarySearch(0, this._file.articleCount, function(i) {
             return that._file.dirEntryByUrlIndex(i).then(function(dirEntry) {
                 if (titleName < dirEntry.url)
                     return -1;
@@ -200,7 +215,7 @@ define(['zimfile', 'zimDirEntry', 'util'],
         }).then(function(index) {
             return that._file.dirEntryByUrlIndex(index);
         }).then(function(dirEntry) {
-            callback(that._dirEntryToTitleObject(dirEntry));
+            return that._dirEntryToTitleObject(dirEntry);
         });
     };
 

www/js/lib/zimfile.js

@@ -159,17 +159,26 @@ define(['xzdec_wrapper', 'util', 'utf8'], function(xz, util, utf8) {
         {
             var clusterOffset = readInt(clusterOffsets, 0, 8);
             var nextCluster = readInt(clusterOffsets, 8, 8);
-            //@todo we assume it is compressed - handle uncompressed (first byte at clusterOffset)
+            return that._readSlice(clusterOffset, 1).then(function(compressionType) {
-            var reader = function(offset, size) {
+                var decompressor;
+                var plainBlobReader = function(offset, size) {
                     return that._readSlice(clusterOffset + 1 + offset, size);
                 };
-            var dec = new xz.Decompressor(reader);
+                if (compressionType[0] === 0 || compressionType[0] === 1) {
-            return dec.readSlice(blob * 4, 8).then(function(data) {
+                    // uncompressed
+                    decompressor = { readSlice: plainBlobReader, end: function() {} };
+                } else if (compressionType[0] === 4) {
+                    decompressor = new xz.Decompressor(plainBlobReader);
+                } else {
+                    return new Uint8Array(); // unsupported compression type
+                }
+                return decompressor.readSlice(blob * 4, 8).then(function(data) {
                     var blobOffset = readInt(data, 0, 4);
                     var nextBlobOffset = readInt(data, 4, 4);
-                return dec.readSlice(blobOffset, nextBlobOffset - blobOffset).then(function(data) {
+                    return decompressor.readSlice(blobOffset, nextBlobOffset - blobOffset).then(function(data) {
-                    dec.end();
+                        decompressor.end();
-                    return utf8.parse(data);
+                        return data;
+                    });
                 });
             });
         });