Updated Chrome app to no longer require domain to be known.

Signed-off-by: Joachim Bauch <bauch@struktur.de>

extensions/chrome/background.js

@@ -1,25 +1,150 @@
-/* global chrome */
+/* global chrome, Promise */
+
+/**
+ * @author Joachim Bauch <bauch@struktur.de>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
 
 (function() {
 
-    /* background page, responsible for actually choosing media */
-    chrome.runtime.onMessageExternal.addListener(function (message, sender, callback) {
-        switch(message.type) {
-            case 'getScreen':
-                chrome.desktopCapture.chooseDesktopMedia(message.options || ['screen', 'window'],
-                                                         sender.tab, function (streamid) {
-                    // communicate this string to the app so it can call getUserMedia with it
-                    message.type = 'gotScreen';
-                    message.sourceId = streamid;
-                    callback(message);
-                    return false;
+    var priority = 100;
+
+    chrome.runtime.onMessage.addListener(function(msg, sender, sendResponse) {
+        switch (msg.type) {
+        case 'init-nc-screensharing':
+            var data = msg.data;
+            var details = chrome.app.getDetails();
+            if (data.extension) {
+                // Existing extension data. Checking id.
+                if (details.id !== data.extension.id) {
+                    // Different extension. Check prio.
+                    if (data.extension.priority && data.extension.priority >= priority) {
+                        // Existing extension has same or higher priority - skip ourselves.
+                        console.log('Refusing to initialize as other extension with same or higher priority found.', data.extension);
+                        return;
+                    } else {
+                        console.log('Refusing to initialize as other extension is already initialized', data.extension);
+                        return;
+                    }
+                }
+            }
+            console.log('Initializing screensharing extension ...', sender.tab.id, data);
+            sendResponse({
+                id: details.id,
+                version: details.version,
+                priority: priority
+            });
+            // Embed our script.
+            chrome.tabs.executeScript(sender.tab.id, {
+                file: 'content.js',
+                runAt: 'document_end'
+            });
+            break;
+        }
+    });
+
+    var ExtensionApi = function(port) {
+        this.port = port;
+    };
+
+    ExtensionApi.prototype.getScreen = function(resolve, reject, msg) {
+        var pending = chrome.desktopCapture.chooseDesktopMedia(['screen', 'window'], this.port.sender.tab, function(id) {
+            var response = {
+                'type': 'gotScreen',
+                'id': msg.id
+            };
+            if (chrome.runtime.lastError) {
+                response.sourceId = '';
+                response.error = chrome.runtime.lastError;
+            } else {
+                response.sourceId = id;
+            }
+            resolve(response);
+        });
+        if (!pending) {
+            return;
+        }
+
+        return {
+            'type': 'getScreenPending',
+            'id': msg.id
+        };
+    };
+
+    ExtensionApi.prototype.call = function(msg) {
+        var api = this;
+        var promise = new Promise(function(resolve, reject) {
+            var f = api[msg.type];
+            if (!f) {
+                reject('action ' + msg.type + ' not found');
+                return;
+            }
+            var response = f.bind(api)(resolve, reject, msg);
+            if (response) {
+                response.answer = true;
+                api.port.postMessage(response);
+            }
+        });
+        promise.then(function(result) {
+            result.answer = true;
+            api.port.postMessage(result);
+        }, function(err) {
+            if (typeof(err) === 'string') {
+                err = {
+                    'error': err
+                };
+            }
+            api.port.postMessage(err);
+        });
+    };
+
+    chrome.runtime.onConnect.addListener(function(port) {
+        var tab = port.sender.tab;
+        var api = new ExtensionApi(port);
+        console.log('Extension connected:', tab.id);
+        port.onMessage.addListener(function(msg) {
+            if (msg.answer) {
+                return;
+            }
+
+            msg.answer = true;
+            api.call(msg);
+        });
+    });
+
+    // Bootstrap directly after install so pages need not be refreshed.
+    chrome.runtime.onInstalled.addListener(function(details) {
+        switch (details.reason) {
+        case 'install':
+        case 'update':
+            console.log('Extension updated or installed', details);
+            chrome.windows.getAll({populate: true}, function(windows) {
+                windows.forEach(function(window) {
+                    window.tabs.forEach(function(tab) {
+                        if (tab.url.match(/https:\/\//gi)) {
+                            chrome.tabs.executeScript(tab.id, {
+                                file: 'detector.js',
+                                runAt: 'document_end'
+                            });
+                        }
+                    });
                 });
-                return true; // retain callback for chooseDesktopMedia result
-            case 'cancelGetScreen':
-                chrome.desktopCapture.cancelChooseDesktopMedia(message.request);
-                message.type = 'canceledGetScreen';
-                callback(message);
-                return false; //dispose callback
+            });
         }
     });
 

extensions/chrome/content.js

@@ -1,7 +1,40 @@
 /* global chrome */
 
+/**
+ * @author Joachim Bauch <bauch@struktur.de>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
 (function() {
 
-    sessionStorage.getScreenMediaJSExtensionId = chrome.runtime.id;
+    var port = chrome.runtime.connect();
+
+    // Forward message from Nextcloud app to the extension.
+    window.addEventListener('message', function(event) {
+        var msg = event.data;
+        if (event.source === window && !msg.answer) {
+            port.postMessage(msg);
+        }
+    });
+
+    // Forward message from the extension to the Nextcloud app.
+    port.onMessage.addListener(function(msg) {
+        window.postMessage(msg, window.document.URL);
+    });
 
 })();

extensions/chrome/detector.js

@@ -0,0 +1,57 @@
+/* global chrome */
+
+/**
+ * @author Joachim Bauch <bauch@struktur.de>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+(function(document) {
+
+	function hasClass(element, cls) {
+		return (' ' + element.className + ' ').indexOf(' ' + cls + ' ') > -1;
+	}
+
+	// Only add extension if the page is running the Nextcloud app.
+	var nc = document.getElementById('app');
+	if (!nc || !hasClass(nc, 'nc-enable-screensharing-extension')) {
+		return;
+	}
+
+	var extension = nc.getAttribute('data-chromExtensionData');
+	if (extension) {
+		try {
+			extension = JSON.parse(extension);
+		} catch (e) {
+			return;
+		}
+	}
+
+	console.log('Detected Nextcloud video calls app.');
+	var msg = {
+		type: 'init-nc-screensharing',
+		data: {
+			extension: extension || null
+		}
+	};
+
+	chrome.runtime.sendMessage(null, msg, null, function(data) {
+		console.log('Initialized extension', data);
+		nc.setAttribute('data-chromExtensionData', JSON.stringify(data));
+	});
+
+}(document));

extensions/chrome/manifest.json

@@ -1,24 +1,28 @@
 {
   "name": "Nextcloud Screensharing",
   "description": "Screensharing utility for the Nextcloud video calls app.",
+  "author": "Joachim Bauch <bauch@struktur.de>"
+  "homepage_url": "https://nextcloud.com",
   "version": "0.0.1",
   "manifest_version": 2,
   "minimum_chrome_version": "34",
   "icons": {
   },
   "permissions": [
-    "desktopCapture"
+    "tabs",
+    "desktopCapture",
+    "https://*/*"
   ],
   "background": {
-    "scripts": ["background.js"]
+    "scripts": ["background.js"],
+    "persistent": false
   },
-  "content_scripts": [ {
-    "js": [ "content.js" ],
-    "matches": [ "https://replace-with-your-hostname/*" ]
-  }],
-  "externally_connectable": {
-      "matches": [
-          "https://replace-with-your-hostname/*"
-      ]
-  }
+  "content_scripts": [
+    {
+      "js": ["detector.js"],
+      "matches": ["https://*/*"],
+      "run_at": "document_end",
+      "all_frames": true
+    }
+  ]
 }