From cdadb0db4d5eaaa2d7bd62a5551d191eeb598ef4 Mon Sep 17 00:00:00 2001 From: Rob Wu Date: Tue, 13 Aug 2013 18:28:13 +0200 Subject: [PATCH] Proof of concept using chrome.streamsPrivate API This method captures all application/pdf streams, loads the viewer and passes the stream to the PDF.js viewer. This commit shows a proof of concept using the chrome.streamsPrivate API. Advantages of new method: - Access to the response body of the original request, thus fewer network requests. - PDFs from non-GET requests (e.g. POST) are now supported. - FTP files are also supported. Possible improvements: - Use declared content scripts instead of dynamic chrome.tabs.executeScript. This allows the extension to render the viewer in frames when the extension is disallowed to run executeScript for the top URL. - Use chrome.declarativeWebRequest instead of webRequest, and replace background page with event page (don't forget to profile the difference & will the background/event page still work as intended?). --- extensions/chromium/manifest.json | 12 ++- extensions/chromium/pdfHandler-v2.js | 105 +++++++++++++++++++++++++++ extensions/chromium/pdfHandler.html | 1 + web/chromecom.js | 46 ++++++++++++ web/viewer.js | 36 ++++++++- 5 files changed, 198 insertions(+), 2 deletions(-) create mode 100644 extensions/chromium/pdfHandler-v2.js create mode 100644 web/chromecom.js diff --git a/extensions/chromium/manifest.json b/extensions/chromium/manifest.json index b709b780d..f19986246 100644 --- a/extensions/chromium/manifest.json +++ b/extensions/chromium/manifest.json @@ -12,12 +12,22 @@ "webRequest", "webRequestBlocking", "", "tabs", - "webNavigation" + "webNavigation", + "streamsPrivate" ], + /* FOR demo & debugging purposes only! This key is required to get access to the streams API. + * This key forces the extension ID to be gbkeegbaiigmenfmjfclcdgdpimamgkj (= Chrome Office Viewer) + * This comment has been added to prevent it from being uploaded to the Chrome Web Store. + * Remove it when the PDF.js extensionID is whitelisted for the streamsPrivate API. + */ + "key": "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC4zyYTii0VTKI7W2U6fDeAvs3YCVZeAt7C62IC64IDCMHvWy7SKMpOPjfg5v1PgYkFm+fGsCsVLN8NaF7fzYMVtjLc5bqhqPAi56Qidrqh1HxPAAYhwFQd5BVGhZmh1fySHXFPE8VI2tIHwRrASOtx67jbSEk4nBAcJz6n+eGq8QIDAQAB", "content_scripts": [{ "matches": ["file://*/*"], "js": ["nothing.js"] }], + "mime_types": [ + "application/pdf" + ], "background": { "page": "pdfHandler.html" }, diff --git a/extensions/chromium/pdfHandler-v2.js b/extensions/chromium/pdfHandler-v2.js new file mode 100644 index 000000000..155eb0e53 --- /dev/null +++ b/extensions/chromium/pdfHandler-v2.js @@ -0,0 +1,105 @@ +/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */ +/* +Copyright 2013 Mozilla Foundation + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +*/ +/* globals chrome, URL, getViewerURL */ + +'use strict'; + +// Hash map of "": "" +var urlToStream = {}; + +// Note: Execution of this script stops when the streamsPrivate API is +// not available, because an error will be thrown. Don't bother with +// catching and handling the error, because it is a great way to see +// when the streamsPrivate API is unavailable. +chrome.streamsPrivate.onExecuteMimeTypeHandler.addListener(handleStream); + +chrome.runtime.onMessage.addListener(function(message, sender, sendResponse) { + if (message && message.action === 'getPDFStream') { + var pdfUrl = message.data; + var streamUrl = urlToStream[pdfUrl]; + // The stream can be used only once. + delete urlToStream[pdfUrl]; + sendResponse({ + streamUrl: streamUrl + }); + } +}); + +/** + * Callback for when we receive a stream + * + * @param mimeType {string} The mime type of the incoming stream + * @param pdfUrl {string} The full URL to the file + * @param streamUrl {string} The url pointing to the open stream + * @param tabId {number} The ID of the tab in which the stream has been opened + * (undefined before Chrome 27, http://crbug.com/225605) + */ +function handleStream(mimeType, pdfUrl, streamUrl, tabId) { + console.log('Intercepted ' + mimeType + ' in tab ' + tabId + ' with URL ' + + pdfUrl + '\nAvailable as: ' + streamUrl); + urlToStream[pdfUrl] = streamUrl; +} + +/** + * Callback for when a navigation error has occurred. + * This event is triggered when the chrome.streamsPrivate API has intercepted + * the PDF stream. This method detects such streams, finds the frame where + * the request was made, and loads the viewer in that frame. + * + * @param details {object} + * @param details.tabId {number} The ID of the tab + * @param details.url {string} The URL being navigated when the error occurred. + * @param details.frameId {number} 0 indicates the navigation happens in the tab + * content window; a positive value indicates + * navigation in a subframe. + * @param details.error {string} + */ +function webNavigationOnErrorOccurred(details) { + var tabId = details.tabId; + var frameId = details.frameId; + var pdfUrl = details.url; + + if (details.error === 'net::ERR_ABORTED') { + if (!urlToStream[pdfUrl]) { + console.log('No saved PDF stream found for ' + pdfUrl); + return; + } + var viewerUrl = getViewerURL(pdfUrl); + + if (frameId === 0) { // Main frame + console.log('Going to render PDF Viewer in main frame for ' + pdfUrl); + chrome.tabs.update(tabId, { + url: viewerUrl + }); + } else { + console.log('Going to render PDF Viewer in sub frame for ' + pdfUrl); + // Non-standard Chrome API. chrome.tabs.executeScriptInFrame and docs + // is available at https://github.com/Rob--W/chrome-api + chrome.tabs.executeScriptInFrame(tabId, { + frameId: frameId, + code: 'location.href = ' + JSON.stringify(viewerUrl) + ';' + }, function(result) { + if (!result) { // Did the tab disappear? Is the frame inaccessible? + console.warn('Frame not found, viewer not rendered in tab ' + tabId); + } + }); + } + } +} + +chrome.webNavigation.onErrorOccurred.addListener(webNavigationOnErrorOccurred); diff --git a/extensions/chromium/pdfHandler.html b/extensions/chromium/pdfHandler.html index dcb70cb31..df35754e0 100644 --- a/extensions/chromium/pdfHandler.html +++ b/extensions/chromium/pdfHandler.html @@ -17,3 +17,4 @@ limitations under the License. + diff --git a/web/chromecom.js b/web/chromecom.js new file mode 100644 index 000000000..6e1a12b59 --- /dev/null +++ b/web/chromecom.js @@ -0,0 +1,46 @@ +/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* Copyright 2013 Mozilla Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +/* globals chrome */ +'use strict'; + +var ChromeCom = (function ChromeComClosure() { + return { + /** + * Creates an event that the extension is listening for and will + * asynchronously respond by calling the callback. + * @param {String} action The action to trigger. + * @param {String} data Optional data to send. + * @param {Function} callback Optional response callback that will be called + * with one data argument. When the request cannot be handled, the callback + * is immediately invoked with no arguments. + */ + request: function(action, data, callback) { + var message = { + action: action, + data: data + }; + if (!chrome.runtime) { + console.error('chrome.runtime is undefined.'); + if (callback) callback(); + } else if (callback) { + chrome.runtime.sendMessage(message, callback); + } else { + chrome.runtime.sendMessage(message); + } + } + }; +})(); diff --git a/web/viewer.js b/web/viewer.js index 516e75ba3..37e45a40e 100644 --- a/web/viewer.js +++ b/web/viewer.js @@ -79,6 +79,10 @@ var mozL10n = document.mozL10n || document.webL10n; //#include firefoxcom.js //#endif +//#if CHROME +//#include chromecom.js +//#endif + var cache = new Cache(CACHE_SIZE); var currentPageNumber = 1; @@ -1770,9 +1774,39 @@ document.addEventListener('DOMContentLoaded', function webViewerLoad(evt) { //return; //#endif -//#if !B2G +//#if !B2G && !CHROME PDFView.open(file, 0); //#endif + +//#if CHROME +//ChromeCom.request('getPDFStream', file, function(response) { +// if (response) { +// // We will only get a response when the streamsPrivate API is available. +// +// var isFTPFile = /^ftp:/i.test(file); +// var streamUrl = response.streamUrl; +// if (streamUrl) { +// console.log('Found data stream for ' + file); +// // The blob stream can be used only once, so disable range requests. +// PDFJS.disableRange = true; +// PDFView.open(streamUrl, 0); +// PDFView.setTitleUsingUrl(file); +// return; +// } +// if (isFTPFile) { +// // Stream not found, and it's loaded from FTP. Reload the page, because +// // it is not possible to get resources over ftp using XMLHttpRequest. +// // NOTE: This will not lead to an infinite redirect loop, because +// // if the file exists, then the streamsPrivate API will capture the +// // stream and send back the response. If the stream does not exist, then +// // a "Webpage not available" error will be shown (not the PDF Viewer). +// location.replace(file); +// return; +// } +// } +// PDFView.open(file, 0); +//}); +//#endif }, true); function updateViewarea() {