SignalR Performance Counters

One of the hidden gems in the SignalR framework is a utility called signalr.exe (in the Microsoft.AspNet.SignalR.Hosting.Utils package) that you can use to do a few things.

• Install/Uninstall SignalR performance counters
• Generate a static js file for the magic ~/signalr/hubs url.

After installing the Microsoft.AspNet.SignalR.Hosting.Utils NuGet package, you’ll find a SignalR executable in the package folder(under \packages\Microsoft.AspNet.SignalR.Hosting.Utils.1.0.0-alpha2\tools)

• Open a command prompt(run as Administrator).
• Browse to the tools folder containing the SignalR.exe file.
• Run signalr ipc to install the Performance Counters. These performance counters give you more detailed information about your SignalR applications.

• Remark: To use these on full IIS you need to add the app pool user for your application to the Performance Monitor Users group.
• Run signalr ghp /path:<path to binaries> to generate a static JavaScript file containing the hub code. This file(server.js) is generated inside the same tools folder.

• If we open up the file we see the magic that SignalR creates for us when calling the ~/signalr/hubs url:

/*!
 * ASP.NET SignalR JavaScript Library v1.0.0
 * http://signalr.net/
 *
 * Copyright Microsoft Open Technologies, Inc. All rights reserved.
 * Licensed under the Apache 2.0
 * https://github.com/SignalR/SignalR/blob/master/LICENSE.md
 *
 */

/// <reference path="..\..\SignalR.Client.JS\Scripts\jquery-1.6.2.js" />
/// <reference path="jquery.signalR.js" />
(function ($, window) {
    /// <param name="$" type="jQuery" />
    "use strict";

    if (typeof ($.signalR) !== "function") {
        throw new Error("SignalR: SignalR is not loaded. Please ensure jquery.signalR-x.js is referenced before ~/signalr/hubs.");
    }

    var signalR = $.signalR;

    function makeProxyCallback(hub, callback) {
        return function () {
            // Call the client hub method
            callback.apply(hub, $.makeArray(arguments));
        };
    }

    function registerHubProxies(instance, shouldSubscribe) {
        var key, hub, memberKey, memberValue, subscriptionMethod;

        for (key in instance) {
            if (instance.hasOwnProperty(key)) {
                hub = instance[key];

                if (!(hub.hubName)) {
                    // Not a client hub
                    continue;
                }

                if (shouldSubscribe) {
                    // We want to subscribe to the hub events
                    subscriptionMethod = hub.on;
                }
                else {
                    // We want to unsubscribe from the hub events
                    subscriptionMethod = hub.off;
                }

                // Loop through all members on the hub and find client hub functions to subscribe/unsubscribe
                for (memberKey in hub.client) {
                    if (hub.client.hasOwnProperty(memberKey)) {
                        memberValue = hub.client[memberKey];

                        if (!$.isFunction(memberValue)) {
                            // Not a client hub function
                            continue;
                        }

                        subscriptionMethod.call(hub, memberKey, makeProxyCallback(hub, memberValue));
                    }
                }
            }
        }
    }

    signalR.hub = $.hubConnection("/signalr", { useDefaultPath: false })
        .starting(function () {
            // Register the hub proxies as subscribed
            // (instance, shouldSubscribe)
            registerHubProxies(signalR, true);

            this._registerSubscribedHubs();
        }).disconnected(function () {
            // Unsubscribe all hub proxies when we "disconnect".  This is to ensure that we do not re-add functional call backs.
            // (instance, shouldSubscribe)
            registerHubProxies(signalR, false);
        });

    signalR.testHub = signalR.hub.createHubProxy('testHub'); 
    signalR.testHub.client = { };
    signalR.testHub.server = {
        test: function () {
            /// <summary>Calls the Test method on the server-side TestHub hub.&#10;Returns a jQuery.Deferred() promise.</summary>
            return signalR.testHub.invoke.apply(signalR.testHub, $.merge(["Test"], $.makeArray(arguments)));
         }
    };

}(window.jQuery, window));