GUAC-1480: Use AllowClipboard and execCommand for local/remote clipboard integration.

guacamole/src/main/webapp/app/client/services/clipboardService.js

@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2016 Glyptodon LLC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+/**
+ * A service for accessing local clipboard data.
+ */
+angular.module('client').factory('clipboardService', ['$injector',
+        function clipboardService($injector) {
+
+    // Get required services
+    var $q         = $injector.get('$q');
+    var $rootScope = $injector.get('$rootScope');
+
+    var service = {};
+
+    /**
+     * A div which is used to hide the clipboard textarea and remove it from
+     * document flow.
+     *
+     * @type Element
+     */
+    var clipElement = document.createElement('div');
+
+    /**
+     * The textarea that will be used to hold the local clipboard contents.
+     *
+     * @type Element
+     */
+    var clipboardContent = document.createElement('textarea');
+
+    /**
+     * The contents of the last clipboard event broadcast by this service when
+     * the clipboard contents changed.
+     *
+     * @type String
+     */
+    var lastClipboardEvent = '';
+
+    clipElement.appendChild(clipboardContent);
+    clipElement.style.position = 'absolute';
+    clipElement.style.width = '0px';
+    clipElement.style.height = '0px';
+    clipElement.style.overflow = 'hidden';
+
+    document.body.appendChild(clipElement);
+
+    /**
+     * Sets the local clipboard, if possible, to the given text.
+     *
+     * @param {String} text
+     *     The text to which the local clipboard should be set.
+     *
+     * @return {Promise}
+     *     A promise that will resolve if setting the clipboard was successful,
+     *     and will reject if it failed.
+     */
+    service.setLocalClipboard = function setLocalClipboard(text) {
+
+        var deferred = $q.defer();
+
+        // First, see if allow clipboard extension is installed
+        if (window.AllowClipboard) {
+
+            var clipboardClient = new AllowClipboard.Client.ClipboardClient();
+
+            clipboardClient.write(text, function(success) {
+                if (success)
+                    deferred.resolve();
+                else
+                    deferred.reject();
+            });
+
+        }
+
+        // Otherwise, try execCommand
+        else {
+
+            // Copy the given value into the clipboard DOM element
+            clipboardContent.value = text;
+            clipboardContent.select();
+
+            // Attempt to copy data from clipboard element into local clipboard
+            if (document.execCommand('copy'))
+                deferred.resolve();
+            else
+                deferred.reject();
+
+        }
+
+        return deferred.promise;
+    };
+
+    /**
+     * Get the current value of the local clipboard.
+     *
+     * @return {Promise}
+     *     A promise that will resolve with the contents of the local clipboard
+     *     if getting the clipboard was successful, and will reject if it
+     *     failed.
+     */
+    service.getLocalClipboard = function getLocalClipboard() {
+
+        var deferred = $q.defer();
+
+        // First, see if allow clipboard extension is installed
+        if (window.AllowClipboard) {
+
+            var clipboardClient = new AllowClipboard.Client.ClipboardClient();
+
+            clipboardClient.read(function(success, data) {
+                if (success)
+                    deferred.resolve(data);
+                else
+                    deferred.reject();
+            });
+
+        }
+
+        // Otherwise, try execCommand
+        else {
+
+            // Clear and select the clipboard DOM element
+            clipboardContent.value = '';
+            clipboardContent.select();
+
+            // Attempt paste local clipboard into clipboard DOM element
+            if (document.execCommand('paste'))
+                deferred.resolve(clipboardContent.value);
+            else
+                deferred.reject();
+
+        }
+
+        return deferred.promise;
+    };
+
+    // Periodically attempt to read the clipboard, firing an event if successful
+    window.setInterval(function periodicallyReadClipboard() {
+        service.getLocalClipboard().then(function clipboardRead(data) {
+
+            // Fire clipboard event if the data has changed
+            if (data !== lastClipboardEvent) {
+               $rootScope.$broadcast('guacClipboard', 'text/plain', data);
+               lastClipboardEvent = data;
+            }
+
+        });
+    }, 100);
+
+    return service;
+
+}]);