A lightweight and extensible Server-Sent Events (SSE) library for .NET
ServerSentEvents is a C# library that simplifies working with Server-Sent Events (SSE) in .NET applications. It provides a structured way to consume, process, and manage SSE connections efficiently.
✅ Abstractions for SSE – Define and implement SSE consumers and processors with ease.
✅ Event Processing – Handle real-time events efficiently using the provided processor.
✅ Flexible & Extensible – Customize components to fit your application's needs.
✅ Blazor & ASP.NET Core Support – Seamlessly integrate with Blazor Server, ASP.NET Core APIs, and other real-time applications.
This repository contains a set of C# libraries for working with Server-Sent Events (SSE). The library is split into three NuGet packages, each serving a distinct purpose:
| Package Name | Description | NuGet Link |
|---|---|---|
| ServerSentEvents.Abstractions | Core interfaces and abstractions for SSE | https://www.nuget.org/packages/ServerSentEvents.Abstractions |
| ServerSentEvents.Consumer | For consuming SSE streams within Blazor WASM project | https://www.nuget.org/packages/ServerSentEvents.Consumer |
| ServerSentEvents.Processor | Processing logic for SSE data within Blazor ASP.NET Hosted project | https://www.nuget.org/packages/ServerSentEvents.Processor |
These packages are designed to work together seamlessly, sharing a common foundation while allowing flexibility for specific use cases.
This package is ideal for:
- Real-time updates – Stock prices, live dashboards, and monitoring systems.
- Live notifications – Chat applications, system alerts, and event-driven workflows.
- Streaming data – Logs, metrics, and continuous data streams.
🔗 GitHub Repository: https://github.com/dotnetnoobie/ServerSentEvents
🔗 Server-sent events: https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events
🔗 Using server-sent events: https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events
🔗 HTML Server-Sent Events API: https://www.w3schools.com/html/html5_serversentevents.asp
📖 Documentation: [Coming Soon]
In Visual Studio Create a Blazor Web App
| Option | Description |
|---|---|
| Framework | .NET 9.0 |
| Interactivite render mode | WebAssembly |
| Interactivity location | Global |
Add a .NET 9.0 class library called Models to your solution
| Project | Description |
|---|---|
| BlazorApp.Models | C# class library shared between the host and client apps which contains message objects |
| BlazorApp | ASP.NET app to host the Blazor WASM client app |
| BlazorApp.Client | Blazor WASM client app |
You can install the package via NuGet Package Manager or the .NET CLI. Below are the commands for each package:
dotnet add package ServerSentEvents.AbstractionsIn a shared project add message objects, example of some simple messages, message objects must implement the IServerSentEvent interface from the ServerSentEvents.Abstractions NuGet package
Concepually message objects are DTO type objects for transporting data
using ServerSentEvents.Abstractions;
namespace BlazorApp.Models;
public record ClearItems() : IServerSentEvent;
public record DemoEvent(DateTime Date) : IServerSentEvent;
public record SportScore(int Team1Score, int Team2Score) : IServerSentEvent;
public record WeatherForecast(DateOnly Date, int TemperatureC, string? Summary) : IServerSentEvent;To use ServerSentEvents.Processor, follow this example:
You can install the package via NuGet Package Manager or the .NET CLI. Below are the commands for each package:
dotnet add package ServerSentEvents.ProcessorAdd to the program.cs file
using ServerSentEvents.Processor;builder.Services.AddHttpClient();
builder.Services.AddServerSentEvents();app.UseServerSentEvents();To use ServerSentEvents.Consumer, follow this example:
You can install the package via NuGet Package Manager or the .NET CLI. Below are the commands for each package:
dotnet add package ServerSentEvents.ConsumerAdd to the program.cs file
builder.AddServerSentEventsConsumer([typeof(ClearItems), typeof(SportScore), typeof(WeatherForecast), typeof(DemoEvent)]);AddServerSentEventsConsumer([]) takes an array of types that implement IServerSentEvent these are the messages that the BlazorApp.Client WASM app will be listerning for from the BlazorApp host project
Add to the MainLayout.razor file
@code {
[Inject] public IServerSentEventConsumer ServerSentEventClient { get; set; } = default!;
}By adding this to the MainLayout.razor file it will automatically connect and listen to the BlazorApp host project for any Server Sent Events