chrome/renderer/resources/extensions/file_system_custom_bindings.js

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // Custom binding for the fileSystem API.
   6
   7 var binding = require('binding').Binding.create('fileSystem');
   8
   9 var fileSystemNatives = requireNative('file_system_natives');
  10 var GetIsolatedFileSystem = fileSystemNatives.GetIsolatedFileSystem;
  11 var lastError = require('lastError');
  12 var sendRequest = require('sendRequest').sendRequest;
  13 var GetModuleSystem = requireNative('v8_context').GetModuleSystem;
  14 // TODO(sammc): Don't require extension. See http://crbug.com/235689.
  15 var GetExtensionViews = requireNative('runtime').GetExtensionViews;
  16
  17 // Fallback to using the current window if no background page is running.
  18 var backgroundPage = GetExtensionViews(-1, 'BACKGROUND')[0] || window;
  19 var backgroundPageModuleSystem = GetModuleSystem(backgroundPage);
  20
  21 // All windows use the bindFileEntryCallback from the background page so their
  22 // FileEntry objects have the background page's context as their own. This
  23 // allows them to be used from other windows (including the background page)
  24 // after the original window is closed.
  25 if (window == backgroundPage) {
  26   var bindFileEntryCallback = function(functionName, apiFunctions) {
  27     apiFunctions.setCustomCallback(functionName,
  28         function(name, request, response) {
  29       if (request.callback && response) {
  30         var callback = request.callback;
  31         request.callback = null;
  32
  33         var entries = [];
  34         var hasError = false;
  35
  36         var getEntryError = function(fileError) {
  37           if (!hasError) {
  38             hasError = true;
  39             lastError.run(
  40                 'fileSystem.' + functionName,
  41                 'Error getting fileEntry, code: ' + fileError.code,
  42                 request.stack,
  43                 callback);
  44           }
  45         }
  46
  47         // Loop through the response entries and asynchronously get the
  48         // FileEntry for each. We use hasError to ensure that only the first
  49         // error is reported. Note that an error can occur either during the
  50         // loop or in the asynchronous error callback to getFile.
  51         $Array.forEach(response.entries, function(entry) {
  52           if (hasError)
  53             return;
  54           var fileSystemId = entry.fileSystemId;
  55           var baseName = entry.baseName;
  56           var id = entry.id;
  57           var fs = GetIsolatedFileSystem(fileSystemId);
  58
  59           try {
  60             var getEntryCallback = function(fileEntry) {
  61               if (hasError)
  62                 return;
  63               entryIdManager.registerEntry(id, fileEntry);
  64               entries.push(fileEntry);
  65               // Once all entries are ready, pass them to the callback. In the
  66               // event of an error, this condition will never be satisfied so
  67               // the callback will not be called with any entries.
  68               if (entries.length == response.entries.length) {
  69                 if (response.multiple) {
  70                   callback(entries);
  71                 } else {
  72                   callback(entries[0]);
  73                 }
  74               }
  75             }
  76             // TODO(koz): fs.root.getFile() makes a trip to the browser process,
  77             // but it might be possible avoid that by calling
  78             // WebFrame::createFileEntry().
  79             if (entry.isDirectory) {
  80               fs.root.getDirectory(baseName, {}, getEntryCallback,
  81                                    getEntryError);
  82             } else {
  83               fs.root.getFile(baseName, {}, getEntryCallback, getEntryError);
  84             }
  85           } catch (e) {
  86             if (!hasError) {
  87               hasError = true;
  88               lastError.run('fileSystem.' + functionName,
  89                             'Error getting fileEntry: ' + e.stack,
  90                             request.stack,
  91                             callback);
  92             }
  93           }
  94         });
  95       }
  96     });
  97   };
  98   var entryIdManager = require('entryIdManager');
  99 } else {
 100   // Force the fileSystem API to be loaded in the background page. Using
 101   // backgroundPageModuleSystem.require('fileSystem') is insufficient as
 102   // requireNative is only allowed while lazily loading an API.
 103   backgroundPage.chrome.fileSystem;
 104   var bindFileEntryCallback = backgroundPageModuleSystem.require(
 105       'fileSystem').bindFileEntryCallback;
 106   var entryIdManager = backgroundPageModuleSystem.require('entryIdManager');
 107 }
 108
 109 binding.registerCustomHook(function(bindingsAPI) {
 110   var apiFunctions = bindingsAPI.apiFunctions;
 111   var fileSystem = bindingsAPI.compiledApi;
 112
 113   function bindFileEntryFunction(functionName) {
 114     apiFunctions.setUpdateArgumentsPostValidate(
 115         functionName, function(fileEntry, callback) {
 116       var fileSystemName = fileEntry.filesystem.name;
 117       var relativePath = $String.slice(fileEntry.fullPath, 1);
 118       return [fileSystemName, relativePath, callback];
 119     });
 120   }
 121   $Array.forEach(['getDisplayPath', 'getWritableEntry', 'isWritableEntry'],
 122                   bindFileEntryFunction);
 123
 124   $Array.forEach(['getWritableEntry', 'chooseEntry', 'restoreEntry'],
 125                   function(functionName) {
 126     bindFileEntryCallback(functionName, apiFunctions);
 127   });
 128
 129   apiFunctions.setHandleRequest('retainEntry', function(fileEntry) {
 130     var id = entryIdManager.getEntryId(fileEntry);
 131     if (!id)
 132       return '';
 133     var fileSystemName = fileEntry.filesystem.name;
 134     var relativePath = $String.slice(fileEntry.fullPath, 1);
 135
 136     sendRequest(this.name, [id, fileSystemName, relativePath],
 137       this.definition.parameters, {});
 138     return id;
 139   });
 140
 141   apiFunctions.setHandleRequest('isRestorable',
 142       function(id, callback) {
 143     var savedEntry = entryIdManager.getEntryById(id);
 144     if (savedEntry) {
 145       callback(true);
 146     } else {
 147       sendRequest(this.name, [id, callback], this.definition.parameters, {});
 148     }
 149   });
 150
 151   apiFunctions.setUpdateArgumentsPostValidate('restoreEntry',
 152       function(id, callback) {
 153     var savedEntry = entryIdManager.getEntryById(id);
 154     if (savedEntry) {
 155       // We already have a file entry for this id so pass it to the callback and
 156       // send a request to the browser to move it to the back of the LRU.
 157       callback(savedEntry);
 158       return [id, false, null];
 159     } else {
 160       // Ask the browser process for a new file entry for this id, to be passed
 161       // to |callback|.
 162       return [id, true, callback];
 163     }
 164   });
 165
 166   // TODO(benwells): Remove these deprecated versions of the functions.
 167   fileSystem.getWritableFileEntry = function() {
 168     console.log("chrome.fileSystem.getWritableFileEntry is deprecated");
 169     console.log("Please use chrome.fileSystem.getWritableEntry instead");
 170     $Function.apply(fileSystem.getWritableEntry, this, arguments);
 171   };
 172
 173   fileSystem.isWritableFileEntry = function() {
 174     console.log("chrome.fileSystem.isWritableFileEntry is deprecated");
 175     console.log("Please use chrome.fileSystem.isWritableEntry instead");
 176     $Function.apply(fileSystem.isWritableEntry, this, arguments);
 177   };
 178
 179   fileSystem.chooseFile = function() {
 180     console.log("chrome.fileSystem.chooseFile is deprecated");
 181     console.log("Please use chrome.fileSystem.chooseEntry instead");
 182     $Function.apply(fileSystem.chooseEntry, this, arguments);
 183   };
 184 });
 185
 186 exports.bindFileEntryCallback = bindFileEntryCallback;
 187 exports.binding = binding.generate();