MDL-28261 Javascript: Check for a working connection in SCORM activities

lang/en/moodle.php

@@ -1210,6 +1210,8 @@ $string['nameforlink'] = 'What do you want to call this link?';
 $string['nameforpage'] = 'Name';
 $string['navigation'] = 'Navigation';
 $string['needed'] = 'Needed';
+$string['networkdropped'] = 'We have detected that your Internet connection is unreliable or has been interrupted.<br />
+Please be aware that changes may not be saved properly until your connection improves.';
 $string['never'] = 'Never';
 $string['neverdeletelogs'] = 'Never delete logs';
 $string['new'] = 'New';

lib/yui/build/moodle-core-checknet/assets/checknet.txt

@@ -0,0 +1 @@
+1

lib/yui/build/moodle-core-checknet/moodle-core-checknet-debug.js

@@ -0,0 +1,194 @@
+YUI.add('moodle-core-checknet', function (Y, NAME) {
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * A utility to check whether the connection to the Moodle server is still
+ * active.
+ *
+ * @module     moodle-core-checknet
+ * @package    core
+ * @copyright  2014 Andrew Nicols <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @main       moodle-core-checknet
+ */
+
+/**
+ * @namespace M.core
+ * @class checknet
+ */
+
+function CheckNet() {
+    CheckNet.superclass.constructor.apply(this, arguments);
+}
+
+Y.extend(CheckNet, Y.Base, {
+    /**
+     * A link to the warning dialogue.
+     *
+     * @property _alertDialogue
+     * @type M.core.dialogue
+     * @private
+     * @default null
+     */
+    _alertDialogue: null,
+
+    /**
+     * Setup the checking mechanism.
+     *
+     * @method initializer
+     */
+    initializer: function() {
+        // Perform our first check.
+        this._scheduleCheck();
+    },
+
+    /**
+     * Schedule a check of the checknet file.
+     *
+     * @method _scheduleCheck
+     * @chainable
+     * @private
+     */
+    _scheduleCheck: function() {
+        // Schedule the next check after five seconds.
+        Y.later(this.get('frequency'), this, this._performCheck);
+
+        return this;
+    },
+
+    /**
+     * Perform an immediate check of the checknet file.
+     *
+     * @method _performCheck
+     * @private
+     */
+    _performCheck: function() {
+        Y.io(this.get('uri'), {
+            data: {
+                // Add a query string to prevent older versions of IE from using the cache.
+                time: new Date().getTime()
+            },
+            timeout: this.get('timeout'),
+            headers: {
+                'Cache-Control': 'no-cache',
+                'Expires': '-1'
+            },
+            context: this,
+            on: {
+                complete: function(tid, response) {
+                    // Check for failure conditions.
+                    // We check for a valid status here because if the user is moving away from the page at the time we
+                    // run this callback we do not want to display the error.
+                    if (response && typeof response.status !== "undefined") {
+                        var code = parseInt(response.status, 10);
+
+                        if (code === 200) {
+                            // This is a valid attempt - clear any existing warning dialogue and destroy it.
+                            if (this._alertDialogue) {
+                                this._alertDialogue.destroy();
+                                this._alertDialogue = null;
+                            }
+                        } else if (code >= 300 && code <= 399) {
+                            // This is a cached status - warn developers, but otherwise ignore.
+                            Y.log("A cached copy of the checknet status file was returned so it's reliablity cannot be guaranteed",
+                                'warn',
+                                'moodle-mod_scorm-checknet');
+                        } else {
+                            if (this._alertDialogue === null || this._alertDialogue.get('destroyed')) {
+                                // Only create a new dialogue if it isn't already displayed.
+                                this._alertDialogue = new M.core.alert({
+                                    message: M.util.get_string.apply(this, this.get('message'))
+                                });
+                            } else {
+                                this._alertDialogue.show();
+                            }
+                        }
+                    }
+
+                    // Start the next check.
+                    this._scheduleCheck();
+                }
+            }
+        });
+    }
+}, {
+    NAME: 'checkNet',
+    ATTRS: {
+        /**
+         * The file to check access against.
+         *
+         * @attribute uri
+         * @type String
+         * @default M.cfg.wwwroot + '/lib/yui/build/moodle-core-checknet/assets/checknet.txt'
+         */
+        uri: {
+            value: M.cfg.wwwroot + '/lib/yui/build/moodle-core-checknet/assets/checknet.txt'
+        },
+
+        /**
+         * The timeout (in milliseconds) before the checker should give up and display a warning.
+         *
+         * @attribute timeout
+         * @type Number
+         * @value 2000
+         */
+        timeout: {
+            value: 2000
+        },
+
+        /**
+         * The frequency (in milliseconds) that checks should be run.
+         * A new check is not begun until the previous check has completed.
+         *
+         * @attribute frequency
+         * @writeOnce
+         * @type Number
+         * @value 5000
+         */
+        frequency: {
+            value: 5000
+        },
+
+        /**
+         * The message which should be displayed upon a test failure.
+         *
+         * The array values are passed directly to M.util.get_string() and arguments should match accordingly.
+         *
+         * @attribute message
+         * @type Array
+         * @value [
+         *  'networkdropped',
+         *  'moodle'
+         * ]
+         */
+        message: {
+            value: [
+                'networkdropped',
+                'moodle'
+            ]
+        }
+    }
+});
+
+M.core = M.core || {};
+M.core.checknet = M.core.checknet || {};
+M.core.checknet.init = function(config) {
+    return new CheckNet(config);
+};
+
+
+}, '@VERSION@', {"requires": ["base-base", "moodle-core-notification-alert", "io-base"]});

lib/yui/build/moodle-core-checknet/moodle-core-checknet-min.js

@@ -0,0 +1 @@
+YUI.add("moodle-core-checknet",function(e,t){function n(){n.superclass.constructor.apply(this,arguments)}e.extend(n,e.Base,{_alertDialogue:null,initializer:function(){this._scheduleCheck()},_scheduleCheck:function(){return e.later(this.get("frequency"),this,this._performCheck),this},_performCheck:function(){e.io(this.get("uri"),{data:{time:(new Date).getTime()},timeout:this.get("timeout"),headers:{"Cache-Control":"no-cache",Expires:"-1"},context:this,on:{complete:function(e,t){if(t&&typeof t.status!="undefined"){var n=parseInt(t.status,10);n===200?this._alertDialogue&&(this._alertDialogue.destroy(),this._alertDialogue=null):n>=300&&n<=399||(this._alertDialogue===null||this._alertDialogue.get("destroyed")?this._alertDialogue=new M.core.alert({message:M.util.get_string.apply(this,this.get("message"))}):this._alertDialogue.show())}this._scheduleCheck()}}})}},{NAME:"checkNet",ATTRS:{uri:{value:M.cfg.wwwroot+"/lib/yui/build/moodle-core-checknet/assets/checknet.txt"},timeout:{value:2e3},frequency:{value:5e3},message:{value:["networkdropped","moodle"]}}}),M.core=M.core||{},M.core.checknet=M.core.checknet||{},M.core.checknet.init=function(e){return new n(e)}},"@VERSION@",{requires:["base-base","moodle-core-notification-alert","io-base"]});

lib/yui/build/moodle-core-checknet/moodle-core-checknet.js

@@ -0,0 +1,191 @@
+YUI.add('moodle-core-checknet', function (Y, NAME) {
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * A utility to check whether the connection to the Moodle server is still
+ * active.
+ *
+ * @module     moodle-core-checknet
+ * @package    core
+ * @copyright  2014 Andrew Nicols <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @main       moodle-core-checknet
+ */
+
+/**
+ * @namespace M.core
+ * @class checknet
+ */
+
+function CheckNet() {
+    CheckNet.superclass.constructor.apply(this, arguments);
+}
+
+Y.extend(CheckNet, Y.Base, {
+    /**
+     * A link to the warning dialogue.
+     *
+     * @property _alertDialogue
+     * @type M.core.dialogue
+     * @private
+     * @default null
+     */
+    _alertDialogue: null,
+
+    /**
+     * Setup the checking mechanism.
+     *
+     * @method initializer
+     */
+    initializer: function() {
+        // Perform our first check.
+        this._scheduleCheck();
+    },
+
+    /**
+     * Schedule a check of the checknet file.
+     *
+     * @method _scheduleCheck
+     * @chainable
+     * @private
+     */
+    _scheduleCheck: function() {
+        // Schedule the next check after five seconds.
+        Y.later(this.get('frequency'), this, this._performCheck);
+
+        return this;
+    },
+
+    /**
+     * Perform an immediate check of the checknet file.
+     *
+     * @method _performCheck
+     * @private
+     */
+    _performCheck: function() {
+        Y.io(this.get('uri'), {
+            data: {
+                // Add a query string to prevent older versions of IE from using the cache.
+                time: new Date().getTime()
+            },
+            timeout: this.get('timeout'),
+            headers: {
+                'Cache-Control': 'no-cache',
+                'Expires': '-1'
+            },
+            context: this,
+            on: {
+                complete: function(tid, response) {
+                    // Check for failure conditions.
+                    // We check for a valid status here because if the user is moving away from the page at the time we
+                    // run this callback we do not want to display the error.
+                    if (response && typeof response.status !== "undefined") {
+                        var code = parseInt(response.status, 10);
+
+                        if (code === 200) {
+                            // This is a valid attempt - clear any existing warning dialogue and destroy it.
+                            if (this._alertDialogue) {
+                                this._alertDialogue.destroy();
+                                this._alertDialogue = null;
+                            }
+                        } else if (code >= 300 && code <= 399) {
+                            // This is a cached status - warn developers, but otherwise ignore.
+                        } else {
+                            if (this._alertDialogue === null || this._alertDialogue.get('destroyed')) {
+                                // Only create a new dialogue if it isn't already displayed.
+                                this._alertDialogue = new M.core.alert({
+                                    message: M.util.get_string.apply(this, this.get('message'))
+                                });
+                            } else {
+                                this._alertDialogue.show();
+                            }
+                        }
+                    }
+
+                    // Start the next check.
+                    this._scheduleCheck();
+                }
+            }
+        });
+    }
+}, {
+    NAME: 'checkNet',
+    ATTRS: {
+        /**
+         * The file to check access against.
+         *
+         * @attribute uri
+         * @type String
+         * @default M.cfg.wwwroot + '/lib/yui/build/moodle-core-checknet/assets/checknet.txt'
+         */
+        uri: {
+            value: M.cfg.wwwroot + '/lib/yui/build/moodle-core-checknet/assets/checknet.txt'
+        },
+
+        /**
+         * The timeout (in milliseconds) before the checker should give up and display a warning.
+         *
+         * @attribute timeout
+         * @type Number
+         * @value 2000
+         */
+        timeout: {
+            value: 2000
+        },
+
+        /**
+         * The frequency (in milliseconds) that checks should be run.
+         * A new check is not begun until the previous check has completed.
+         *
+         * @attribute frequency
+         * @writeOnce
+         * @type Number
+         * @value 5000
+         */
+        frequency: {
+            value: 5000
+        },
+
+        /**
+         * The message which should be displayed upon a test failure.
+         *
+         * The array values are passed directly to M.util.get_string() and arguments should match accordingly.
+         *
+         * @attribute message
+         * @type Array
+         * @value [
+         *  'networkdropped',
+         *  'moodle'
+         * ]
+         */
+        message: {
+            value: [
+                'networkdropped',
+                'moodle'
+            ]
+        }
+    }
+});
+
+M.core = M.core || {};
+M.core.checknet = M.core.checknet || {};
+M.core.checknet.init = function(config) {
+    return new CheckNet(config);
+};
+
+
+}, '@VERSION@', {"requires": ["base-base", "moodle-core-notification-alert", "io-base"]});

lib/yui/src/checknet/assets/checknet.txt

@@ -0,0 +1 @@
+1

lib/yui/src/checknet/build.json

@@ -0,0 +1,10 @@
+{
+    "name": "moodle-core-checknet",
+    "builds": {
+        "moodle-core-checknet": {
+            "jsfiles": [
+                "checknet.js"
+            ]
+        }
+    }
+}

lib/yui/src/checknet/js/checknet.js

@@ -0,0 +1,189 @@
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * A utility to check whether the connection to the Moodle server is still
+ * active.
+ *
+ * @module     moodle-core-checknet
+ * @package    core
+ * @copyright  2014 Andrew Nicols <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @main       moodle-core-checknet
+ */
+
+/**
+ * @namespace M.core
+ * @class checknet
+ */
+
+function CheckNet() {
+    CheckNet.superclass.constructor.apply(this, arguments);
+}
+
+Y.extend(CheckNet, Y.Base, {
+    /**
+     * A link to the warning dialogue.
+     *
+     * @property _alertDialogue
+     * @type M.core.dialogue
+     * @private
+     * @default null
+     */
+    _alertDialogue: null,
+
+    /**
+     * Setup the checking mechanism.
+     *
+     * @method initializer
+     */
+    initializer: function() {
+        // Perform our first check.
+        this._scheduleCheck();
+    },
+
+    /**
+     * Schedule a check of the checknet file.
+     *
+     * @method _scheduleCheck
+     * @chainable
+     * @private
+     */
+    _scheduleCheck: function() {
+        // Schedule the next check after five seconds.
+        Y.later(this.get('frequency'), this, this._performCheck);
+
+        return this;
+    },
+
+    /**
+     * Perform an immediate check of the checknet file.
+     *
+     * @method _performCheck
+     * @private
+     */
+    _performCheck: function() {
+        Y.io(this.get('uri'), {
+            data: {
+                // Add a query string to prevent older versions of IE from using the cache.
+                time: new Date().getTime()
+            },
+            timeout: this.get('timeout'),
+            headers: {
+                'Cache-Control': 'no-cache',
+                'Expires': '-1'
+            },
+            context: this,
+            on: {
+                complete: function(tid, response) {
+                    // Check for failure conditions.
+                    // We check for a valid status here because if the user is moving away from the page at the time we
+                    // run this callback we do not want to display the error.
+                    if (response && typeof response.status !== "undefined") {
+                        var code = parseInt(response.status, 10);
+
+                        if (code === 200) {
+                            // This is a valid attempt - clear any existing warning dialogue and destroy it.
+                            if (this._alertDialogue) {
+                                this._alertDialogue.destroy();
+                                this._alertDialogue = null;
+                            }
+                        } else if (code >= 300 && code <= 399) {
+                            // This is a cached status - warn developers, but otherwise ignore.
+                            Y.log("A cached copy of the checknet status file was returned so it's reliablity cannot be guaranteed",
+                                'warn',
+                                'moodle-mod_scorm-checknet');
+                        } else {
+                            if (this._alertDialogue === null || this._alertDialogue.get('destroyed')) {
+                                // Only create a new dialogue if it isn't already displayed.
+                                this._alertDialogue = new M.core.alert({
+                                    message: M.util.get_string.apply(this, this.get('message'))
+                                });
+                            } else {
+                                this._alertDialogue.show();
+                            }
+                        }
+                    }
+
+                    // Start the next check.
+                    this._scheduleCheck();
+                }
+            }
+        });
+    }
+}, {
+    NAME: 'checkNet',
+    ATTRS: {
+        /**
+         * The file to check access against.
+         *
+         * @attribute uri
+         * @type String
+         * @default M.cfg.wwwroot + '/lib/yui/build/moodle-core-checknet/assets/checknet.txt'
+         */
+        uri: {
+            value: M.cfg.wwwroot + '/lib/yui/build/moodle-core-checknet/assets/checknet.txt'
+        },
+
+        /**
+         * The timeout (in milliseconds) before the checker should give up and display a warning.
+         *
+         * @attribute timeout
+         * @type Number
+         * @value 2000
+         */
+        timeout: {
+            value: 2000
+        },
+
+        /**
+         * The frequency (in milliseconds) that checks should be run.
+         * A new check is not begun until the previous check has completed.
+         *
+         * @attribute frequency
+         * @writeOnce
+         * @type Number
+         * @value 5000
+         */
+        frequency: {
+            value: 5000
+        },
+
+        /**
+         * The message which should be displayed upon a test failure.
+         *
+         * The array values are passed directly to M.util.get_string() and arguments should match accordingly.
+         *
+         * @attribute message
+         * @type Array
+         * @value [
+         *  'networkdropped',
+         *  'moodle'
+         * ]
+         */
+        message: {
+            value: [
+                'networkdropped',
+                'moodle'
+            ]
+        }
+    }
+});
+
+M.core = M.core || {};
+M.core.checknet = M.core.checknet || {};
+M.core.checknet.init = function(config) {
+    return new CheckNet(config);
+};

lib/yui/src/checknet/meta/checknet.json

@@ -0,0 +1,9 @@
+{
+    "moodle-core-checknet": {
+        "requires": [
+            "base-base",
+            "moodle-core-notification-alert",
+            "io-base"
+        ]
+    }
+}

mod/scorm/lang/en/scorm.php

@@ -250,6 +250,8 @@ There are 3 options:
 $string['navdesc'] = 'This setting specifies whether to show or hide navigation buttons and their position.';
 $string['navpositionleft'] = 'Position of navigation buttons from left in pixels.';
 $string['navpositiontop'] = 'Position of navigation buttons from top in pixels.';
+$string['networkdropped'] = 'The SCORM player has determined that your Internet connection is unreliable or has been interrupted. If you continue in this SCORM activity, your progress may not be saved.<br />
+You should exit the activity now, and return when you have a dependable Internet connection.';
 $string['newattempt'] = 'Start a new attempt';
 $string['next'] = 'Continue';
 $string['noactivity'] = 'Nothing to report';

mod/scorm/player.php

@@ -257,4 +257,10 @@ if (empty($scorm->popup) || $displaymode == 'popup') {
 if (!empty($forcejs)) {
     echo $OUTPUT->box(get_string("forcejavascriptmessage", "scorm"), "generalbox boxaligncenter forcejavascriptmessage");
 }
+
+// Add the checknet system to keep checking for a connection.
+$PAGE->requires->string_for_js('networkdropped', 'mod_scorm');
+$PAGE->requires->yui_module('moodle-core-checknet', 'M.core.checknet.init', array(array(
+    'message' => array('networkdropped', 'mod_scorm'),
+)));
 echo $OUTPUT->footer();