Implemented async delivery of server events.

Fixed center alignment: only the login page needs to be centered.

1 files changed, 50 insertions, 159 deletions

diff --git a/js/codeq/comms.js b/js/codeq/comms.js
index f32b4db..de6f918 100644
--- a/js/codeq/comms.js
+++ b/js/codeq/comms.js
@@ -1,157 +1,3 @@
-/*(function () {
-
-    var send = function (service, json) {
-        if (json instanceof Object) json = codeq.jsonize(json);
-        return Q.Promise(function (resolve, reject, notify) {
-            $.ajax({
-                'type': 'POST',
-                'url': codeq.urlPrefix + service,
-                'accepts': 'application/json',
-                'contentType': 'application/json; charset=UTF-8', // type of our request
-                'data': json,
-                'processData': false, // don't process outgoing data
-                'dataType': 'json', // expected type of the response
-                'timeout': 60000, // one minute
-                'error': function sendErrorHandler(jqXHR, textStatus, errorThrown) {
-                    reject(new Error(errorThrown || textStatus));
-                },
-                'success': function sendSuccessHandler(data, textStatus, jqXHR) {
-                    resolve(data);
-                }
-            });
-        });
-    };
-
-    var activities = {}, // keyed by problem_id: activity info waiting to be sent to the server
-        activityKeys = [], // the keys to activities dictionary
-        resolveActivity = function (promiseResolvers) {
-            var i;
-            // signal everyone that the queue is flushed
-            for (i = 0; i < promiseResolvers.length; i++) {
-                try {
-                    promiseResolvers[i][0]();
-                }
-                catch (e) {}
-            }
-            promiseResolvers.length = 0;
-        },
-        sendActivityInternal = function () {
-            var activityKey, activityDescriptor, trace, sendCount;
-            // send max. 100 activities, do not be excessive
-            if (activityKeys.length == 0) return;
-            activityKey = activityKeys[0];
-            activityDescriptor = activities[activityKey];
-            trace = activityDescriptor.trace;
-            if (trace.length > 100) {
-                sendCount = 100;
-                trace = trace.slice(0, 100);
-            }
-            else {
-                sendCount = trace.length;
-            }
-            send('activity', {'trace': trace, 'solution': activityDescriptor.solution, 'problem_id': activityDescriptor.problem_id, 'sid': codeq.sid}).then(
-                function sendActivitySuccess() {
-                    activityDescriptor.trace.splice(0, sendCount);
-                    if (activityDescriptor.trace.length > 0) sendActivityInternal();
-                    else {
-                        delete activities[activityKey];
-                        activityKeys.shift();
-                        resolveActivity(activityDescriptor.promiseResolvers);
-                    }
-                },
-                function sendActivityFailure() {
-                    Q.delay(500).then(sendActivityInternal).done();
-                }
-            ).done();
-        };
-
-    codeq.comms = {
-        sendActivity: function commsSendActivity (trace, solution, problem_id) {
-            return Q.Promise(function (resolve, reject, notify) {
-                var triggerSending = activityKeys.length == 0,
-                    activityDescriptor = activities[problem_id],
-                    problemTrace, promiseResolvers, i;
-                if (!activityDescriptor) {
-                    problemTrace = [];
-                    promiseResolvers = [];
-                    activityDescriptor = {
-                        'problem_id': problem_id,
-                        'trace': problemTrace,
-                        'solution': solution,
-                        'promiseResolvers': promiseResolvers
-                    };
-                    activities[problem_id] = activityDescriptor;
-                    activityKeys.push(problem_id);
-                }
-                else {
-                    problemTrace = activityDescriptor.trace;
-                    promiseResolvers = activityDescriptor.promiseResolvers;
-                    if (solution) activityDescriptor.solution = solution;
-                }
-                if (trace instanceof Array) {
-                    for (i = 0; i < trace.length; i++) {
-                        problemTrace.push(trace[i]);
-                    }
-                }
-                else {
-                    problemTrace.push(trace);
-                }
-                promiseResolvers.push([resolve, reject]);
-                if (triggerSending) {
-                    setTimeout(sendActivityInternal, 0); // async trigger: see if you can collect some more payload
-                }
-            });
-        },
-
-        sendQuery: function commsSendQuery (query, problem_id) {
-            var existingActivity = activities[problem_id],
-                tmp;
-            query['sid'] = codeq.sid;
-            if (existingActivity) {
-                tmp = query['trace'];
-                if (tmp) {
-                    // the trace will be sent separately, so it will be in the proper order
-                    tmp.splice(0, 0, existingActivity.trace.length, 0); // add two parameters in front, they will form the first two parameters to the following splice() invocation
-                    existingActivity.trace.splice.apply(existingActivity.trace, tmp);
-                    delete query['trace'];
-                }
-                tmp = query['program'];
-                if (tmp) existingActivity.solution = tmp;
-            }
-            return send('query', query);
-        },
-
-        sendPush: function commsSendPush (json) {
-            json['sid'] = codeq.sid;
-            return send('python_push', json);
-        },
-
-        sendPull: function commsSendPull (json) {
-            json['sid'] = codeq.sid;
-            return send('python_pull', json);
-        },
-
-        sendHint: function commsSendHint (json) {
-            json['sid'] = codeq.sid;
-            return send('hint', json);
-        },
-
-        sendTest: function commsSendTest (json) {
-            json['sid'] = codeq.sid;
-            return send('test', json);
-        },
-
-        getProblem: function commsGetProblem (language, problem_group, problem) {
-            return send('get_problem', {
-                'sid': codeq.sid,
-                'language': language,
-                'problem_group': problem_group,
-                'problem': problem
-            });
-        }
-    };
-})();*/
-
 (function () {
     var BinaryMessageError = function (message) {
         var e = new Error(message);
@@ -182,10 +28,10 @@
         reconnectTimer = null,
         login_username = null,
         login_password = null,
-
         waiters = {}, // keyed by TID: {packet, created, promise}
         connected = false,
         connectPromise = null,
+        requestHandlers = {}, // handlers for requests (events) from the server, keyed by event ID, value is an array of handlers
         handleIncomingMessageError = function (error, data) {
             if (error instanceof BinaryMessageError) {
                 codeq.log.error('Incoming message is not a string, attempting reconnect');
@@ -215,7 +61,7 @@
             }
         },
         onMessage = function (data) {
-            var m, waiter;
+            var m, waiter, event, handlers, i, N;
 
             try {
                 m = parseData(data);
@@ -237,11 +83,25 @@
                     codeq.log.debug('There is noone waiting for the incoming message, TID=' + m.tid);
                 }
             }
-            else {
-                codeq.log.debug('Incoming message without a TID, handing it off to handlers');
+
+            event = m.event;
+            if (typeof event !== 'string') {
+                codeq.log.warn('Incoming message without a TID and with no event name, dropping it on the floor: ' + data);
+                return;
             }
 
-            // TODO handle message delivery
+            handlers = requestHandlers[event];
+            if (!handlers) {
+                codeq.log.warn('Incoming event message cannot be handled: no handler registered for ' + event);
+                return;
+            }
+
+            N = handlers.length;
+            for (i = 0; i < N; i++) {
+                setTimeout((function (handler) {return function () {
+                    handler(m);
+                }})(handlers[i]), 0);
+            }
         },
         onConnect = function () {
             var tid, sortedWaiters = [], i;
@@ -417,6 +277,37 @@
                 'problem_group': problem_group,
                 'problem': problem
             });
+        },
+
+        'on': function (event, handler) {
+            var handlers = requestHandlers[event],
+                N, i;
+            if (!handlers) {
+                handlers = [handler];
+                requestHandlers[event] = handlers;
+                return;
+            }
+            N = handlers.length;
+            for (i = 0; i < N; i++) {
+                if (handlers[i] === handler) return; // already registered
+            }
+            handlers.push(handler);
+        },
+
+        'off': function (event, handler) {
+            var handlers = requestHandlers[event],
+                N, i;
+            if (!handlers) return; // none registered
+            N = handlers.length;
+            for (i = 0; i < N; i++) {
+                if (handlers[i] === handler) {
+                    handlers.splice(i, 1);
+                    if (handlers.length === 0) {
+                        delete requestHandlers[event];
+                    }
+                    return;
+                }
+            }
         }
     };
 })();