Welcome to a collection of Fusion samples!

All project updates are published on its Discord Server; it's also the best place for Q/A.

Fusion-style HelloWorld shows how to create simple dependency chains and react to invalidation events. Its Program.cs is just about 40 lines long.

HelloBlazorServer is a default Blazor Server App modified to reveal some Fusion powers. Contrary to the original app:

• It displays changes made to a global counter in real-time
• Similarly, it updates weather forecasts in real-time
• A new "Simple Chat" sample shows a bit more complex update scenario and features a simple chat bot.

If you're curious how big is the difference between the code of these samples and a similar code without any real-time features, check out this part of Fusion README.md.

It's a dual-mode Blazor SPA hosted by ASP.NET Core website, which also serves its API. The application includes:

• "Server Time" and "Server Screen" pages showing the simplest timeout-based invalidation
• "Chat" – a tiny chat relying on event-based invalidation
• "Composition" shows how Fusion tracks and updates a complex state built from the output of Compute Services (local producers) and Replica Services (remote producers)
• "Authentication" – a GitHub authentication sample with Google-style real-time session tracking, "Kick", and "Sign-out everywhere" actions.

Check out a 7-min. video walk-through for this sample - the animations below show just some of its features.

Note that "Composition" sample shown in a separate window in the bottom-right corner also properly updates everything. It shows Fusion's ability to use both local IComputed<T> instances and client-side replicas of similar server-side instances to compute a new value that properly tracks all these dependencies and updates accordingly:

• First panel's UI model is composed on the server-side; its client-side replica is bound to the component displaying the panel
• And the second panel uses an UI model composed completely on the client by combining server-side replicas of all the values used there.
• The surprising part: two above files are almost identical!

The sample supports both (!) Server-Side Blazor and Blazor WebAssembly modes – you can switch the mode on its "Home" page.

Moreover, it also exposes a regular RESTful API – try invoking any of endpoints there right from embedded Swagger console.

It's a console app running the benchmark (Client) + ASP.NET Core API Server. Its output on Ryzen Threadripper 3960X:

Local services:
Fusion's Compute Service [-> EF Core -> SQL Server]:
  Reads         : 27.55M operations/s
Regular Service [-> EF Core -> SQL Server]:
  Reads         : 25.05K operations/s

Remote services:
Fusion's Replica Client [-> HTTP+WebSocket -> ASP.NET Core -> Compute Service -> EF Core -> SQL Server]:
  Reads         : 20.29M operations/s
RestEase Client [-> HTTP -> ASP.NET Core -> Compute Service -> EF Core -> SQL Server]:
  Reads         : 127.96K operations/s
RestEase Client [-> HTTP -> ASP.NET Core -> Regular Service -> EF Core -> SQL Server]:
  Reads         : 20.46K operations/s

What's interesting in this output?

• Fusion-backed API endpoint serving relatively small amount of cacheable data scales to ~ 130,000 RPS while running the test on the same machine (that's a disadvantage).
• Identical EF Core-based API endpoint scales to just 20K RPS.

So there is a ~ 6.5x difference for an extremely simple EF Core service hitting a tiny DB running in simple recovery mode. In other words, use of Fusion on server-side only brings ~ an order of magnitude performance boost even when there is almost nothing to speed up!

Besides that, the test shows Replica Services scale ~ almost as local Compute Services, i.e. to ~ 20 million "RPS". These aren't true RPS, of course - Replica Service simply kills any RPC for cached values that are known to be consistent. But nevertheless, it's still a pretty unique feature Fusion brings to the table – and that's exactly what allows it Blazor samples to share the same code for both WASM and SSB modes. So even though Replica Service is just a client for remote Compute Service, its performance is very similar!

It's interactive – you can simply browse it, but to modify and run the C# code presented there, you need Try .NET or Docker.

Build & run locally with .NET 5.0 SDK:

Build & run with Docker + Docker Compose:

# Run this command first
docker-compose build

• Check out Fusion repository on GitHub
• Go to Documentation Home
• Join our Discord Server or Gitter to ask questions and track project updates.

P.S. If you've already spent some time learning about Fusion, please help us to make it better by completing Fusion Feedback Form (1…3 min).