Fusillade: An opinionated HTTP library for Mobile Development

Fusillade helps you to write more efficient code in mobile and desktop applications written in C#. Its design goals and feature set are inspired by Volley as well as Picasso.

What even does this do for me?

Fusillade is a set of HttpMessageHandlers (i.e. "drivers" for HttpClient) that make your mobile applications more efficient and responsive:

• Auto-deduplication of requests - if every instance of your TweetView class requests the same avatar image, Fusillade will only do one request and give the result to every instance.

• Request Limiting - Requests are always dispatched 4 at a time (the Volley default) - issue lots of requests without overwhelming the network connection.

• Request Prioritization - background requests should run at a lower priority than requests initiated by the user, but actually implementing this is quite difficult. With a few changes to your app, you can hint to Fusillade which requests should skip to the front of the queue.

• Speculative requests - On page load, many apps will try to speculatively cache data (i.e. try to pre-download data that the user might click on). Marking requests as speculative will allow requests until a certain data limit is reached, then cancel future requests (i.e. "Keep downloading data in the background until we've got 5MB of cached data")

How do I use it?

The easiest way to interact with Fusillade is via a class called NetCache, which has a number of built-in scenarios:

public static class NetCache
{
    // Use to fetch data into a cache when a page loads. Expect that
    // these requests will only get so far then give up and start failing
    public static HttpMessageHandler Speculative { get; set; }

    // Use for network requests that are running in the background
    public static HttpMessageHandler Background { get; set; }

    // Use for network requests that are fetching data that the user is
    // waiting on *right now*
    public static HttpMessageHandler UserInitiated { get; set; }
}

To use them, just create an HttpClient with the given handler:

var client = new HttpClient(NetCache.UserInitiated);
var response = await client.GetAsync("http://httpbin.org/get");
var str = await client.Content.ReadAsStringAsync();

Console.WriteLine(str);

Where does it work?

Everywhere! Fusillade is a Portable Library, it works on:

• Xamarin.Android
• Xamarin.iOS
• Xamarin.Mac
• Windows Desktop apps
• WinRT / Windows Phone 8.1 apps
• Windows Phone 8

More on speculative requests

Generally, on a mobile app, you'll want to reset the Speculative limit every time the app resumes from standby. How you do this depends on the platform, but in that callback, you need to call:

NetCache.Speculative.ResetLimit(1048576 * 5/*MB*/);

How do I use this with ModernHttpClient?

Add this line to a static constructor of your app's startup class:

using Splat;

Locator.CurrentMutable.RegisterConstant(new NativeMessageHandler(), typeof(HttpMessageHandler));

Statics? That sucks! I like $OTHER_THING! Your priorities suck, I want to come up with my own scheme!

NetCache is just a nice pre-canned default, the interesting code is in a class called RateLimitedHttpMessageHandler. You can create it explicitly and configure it as-needed.

What's with the name?

The word 'Fusillade' is a synonym for Volley :)