How to minify SignalR

Question

I have the following in my Index.cshtml :

    @Scripts.Render("/signalr/hubs")

In my BundleConfig.cs , I have the following:

    .Include("~/Scripts/jquery.signalR-{version}.min.js")

With EnableOptimizations on, I get a nicely bundled vendor? package. But in my Sources , I see:

Why is this raw unminified JS getting loaded? How do I bundle/minify it?

Answer 1

SignalR's proxy scripts are dynamically generated at runtime at /signalr/hubs by default. They're typically small, on the order of a couple of kilobytes or smaller, so minifying them will not yield any performance benefits (perhaps zero benefit at all if they already fit into an entire Ethernet frame).

Additionally, the hubs themselves cannot have their internal symbols/identifiers minified because it exposes a "public API" that your code consumes - see how dynamic (or interfaced) "client method" calls inside your Hub class are transferred over the pipe, so those names must be preserved for the system to work.

Finally, IIS is usually configured to HTTP gzip-compress certain dynamically-generated content anyway, this includes the SignalR proxy scripts - further minification can be counterproductive (as the entropy of minified scripts can be higher than uncompressed scripts).

But if you believe you can safely compress them, or if you want to bundle them, and you're certain you don't need the benefit of dynamically-generated proxies to handle rapidly changing developer requirements, then you can generate them offline:

https://docs.microsoft.com/en-us/aspnet/signalr/overview/guide-to-the-api/hubs-api-guide-javascript-client

How to create a physical file for the SignalR generated proxy

As an alternative to the dynamically generated proxy, you can create a physical file that has the proxy code and reference that file. You might want to do that for control over caching or bundling behavior, or to get IntelliSense when you are coding calls to server methods.

1. Install the Microsoft.AspNet.SignalR.Utils NuGet package.
2. Open a command prompt and browse to the tools folder that contains the SignalR.exe file. The tools folder is at the following location: packages\\Microsoft.AspNet.SignalR.Utils.2.1.0\\tools
3. signalr ghp /path:[path to the .dll that contains your Hub class] - This command creates a file named server.js in the same folder as signalr.exe.
4. Put the server.js file in an appropriate folder in your project, rename it as appropriate for your application, and add a reference to it in place of the "signalr/hubs" reference.