Add template for Server Sent Events (SSE)

README.md

@@ -23,6 +23,7 @@ To use one of the templates below, create a new folder and run `dotnet new <temp
 | `genhttp-webservice-minimal`     | A project that will host a new [REST web service](https://genhttp.org/documentation/content/frameworks/functional/) in a single file.                   |
 | `genhttp-webservice-controllers` | A project that will host a new REST web service using [controllers](https://genhttp.org/documentation/content/frameworks/controllers/).                 |
 | `genhttp-websocket`              | A project providing a web socket endpoint using the [websocket](https://genhttp.org/documentation/content/frameworks/websockets/) framework.            |
+| `genhttp-sse`                    | A project providing a SSE event source using the [Server Sent Events](https://genhttp.org/documentation/content/handlers/server-sent-events/) handler.  |
 | `genhttp-website-static`         | Project to serve a [static website](https://genhttp.org/documentation/content/frameworks/static-websites/) from the file system.                        |
 | `genhttp-spa`                    | Project to serve the distribution files of a [Single Page Application](https://genhttp.org/documentation/content/frameworks/single-page-applications/). |
 

Templates/ServerSentEvents/$safeprojectname$.Tests/$safeprojectname$.Tests.csproj

@@ -0,0 +1,28 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+
+    <TargetFramework>net9.0</TargetFramework>
+
+    <Nullable>enable</Nullable>
+    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <ImplicitUsings>true</ImplicitUsings>
+
+    <IsPackable>false</IsPackable>
+
+  </PropertyGroup>
+
+  <ItemGroup>
+
+	<PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+
+	<PackageReference Include="MSTest.TestAdapter" Version="3.6.4" />
+	<PackageReference Include="MSTest.TestFramework" Version="3.6.4" />
+
+    <PackageReference Include="GenHTTP.Testing" Version="9.4.0" />
+
+    <ProjectReference Include="..\$safeprojectname$\$safeprojectname$.csproj" />
+
+  </ItemGroup>
+
+</Project>

Templates/ServerSentEvents/$safeprojectname$.Tests/EventStreamTest.cs

@@ -0,0 +1,23 @@
+using System.Net;
+
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+using GenHTTP.Testing;
+
+namespace $safeprojectname$.Tests;
+
+[TestClass]
+public class EventStreamTests
+{
+
+    [TestMethod]
+    public async Task TestIndexServed()
+    {
+        await using var runner = await TestHost.RunAsync(Project.Setup());
+
+        using var response = await runner.GetResponseAsync();
+
+        Assert.AreEqual(HttpStatusCode.OK, response.StatusCode);
+    }
+
+}

Templates/ServerSentEvents/$safeprojectname$/$safeprojectname$.csproj

@@ -0,0 +1,34 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net9.0</TargetFramework>
+
+    <Nullable>enable</Nullable>
+    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <ImplicitUsings>true</ImplicitUsings>
+
+    <AssemblyVersion>0.1.0.0</AssemblyVersion>
+    <FileVersion>0.1.0.0</FileVersion>
+    <Version>0.1.0</Version>
+
+	<ServerGarbageCollection>true</ServerGarbageCollection>
+
+  </PropertyGroup>
+
+  <ItemGroup>
+
+    <PackageReference Include="GenHTTP.Core" Version="9.4.0" />
+
+    <PackageReference Include="GenHTTP.Modules.ServerSentEvents" Version="9.4.0" />
+
+  </ItemGroup>
+
+  <ItemGroup>
+
+    <EmbeddedResource Include="Resources\client.html" />
+
+  </ItemGroup>
+
+</Project>

Templates/ServerSentEvents/$safeprojectname$/Program.cs

@@ -0,0 +1,31 @@
+using GenHTTP.Engine.Internal;
+
+using GenHTTP.Modules.Practices;
+
+using $safeprojectname$;
+
+//
+// GenHTTP Server Sent Events Template
+//
+// URLs:
+//   http://localhost:8080/
+//
+// Handler documentation:
+//   https://genhttp.org/documentation/content/handlers/server-sent-events/
+//
+// Additional features:
+//   https://genhttp.org/documentation/content/
+//
+
+var project = Project.Setup();
+
+return await Host.Create()
+                 .Handler(project)
+                 .Defaults()
+                 .Console()
+//-:cnd:noEmit
+#if DEBUG
+                 .Development()
+#endif
+//+:cnd:noEmit
+                 .RunAsync();

Templates/ServerSentEvents/$safeprojectname$/Project.cs

@@ -0,0 +1,43 @@
+using GenHTTP.Api.Content;
+
+using GenHTTP.Modules.IO;
+using GenHTTP.Modules.Layouting;
+using GenHTTP.Modules.ServerSentEvents;
+
+namespace $safeprojectname$;
+
+public static class Project
+{
+
+    public static IHandlerBuilder Setup()
+    {
+        var client = Content.From(Resource.FromAssembly("client.html"));
+
+        var stocks = EventSource.Create()
+                                .Generator(GenerateStock);
+
+        return Layout.Create()
+                     .Add("stock", stocks)
+                     .Index(client);
+    }
+
+    private static async ValueTask GenerateStock(IEventConnection connection)
+    {
+        var rand = new Random();
+
+        var stockSymbols = new List<string> { "AAPL", "GOOGL", "MSFT" };
+
+        await connection.CommentAsync("Sending stock data");
+
+        while (connection.Connected)
+        {
+            var symbol = stockSymbols[rand.Next(0, 3)];
+
+            await connection.DataAsync(rand.Next(100, 1000), symbol);
+
+            await Task.Delay(1000);
+        }
+
+    }
+
+}

Templates/ServerSentEvents/$safeprojectname$/Resources/client.html

@@ -0,0 +1,68 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Stock Tracker</title>
+    <style>
+        body {
+            font-family: Arial, sans-serif;
+        }
+        #stocks {
+            display: flex;
+            flex-direction: column;
+            gap: 10px;
+            margin-top: 20px;
+        }
+        .stock {
+            padding: 10px;
+            border: 1px solid #ddd;
+            border-radius: 5px;
+            background-color: #f9f9f9;
+        }
+    </style>
+</head>
+<body>
+<h1>Stock Tracker</h1>
+<div id="stocks"></div>
+
+<script>
+    // Establish a connection to the server using Server-Sent Events
+    const eventSource = new EventSource('http://localhost:8080/stock/');
+
+    // Function to display stock updates
+    function updateStock(symbol, value) {
+        let stockElement = document.getElementById(symbol);
+
+        if (!stockElement) {
+            // Create a new element for the stock symbol if it doesn't exist
+            stockElement = document.createElement('div');
+            stockElement.id = symbol;
+            stockElement.className = 'stock';
+            document.getElementById('stocks').appendChild(stockElement);
+        }
+
+        // Update stock value
+        stockElement.innerHTML = `<strong>${symbol}:</strong> ${value}`;
+    }
+
+    // Event listener for general updates
+    eventSource.onmessage = function(event) {
+        updateStock(event.type, event.data);
+    };
+
+    // Event listeners for specific stock symbols
+    const symbols = ['AAPL', 'GOOGL', 'MSFT']; // Example stocks
+    symbols.forEach(symbol => {
+        eventSource.addEventListener(symbol, event => {
+            updateStock(symbol, event.data);
+        });
+    });
+
+    // Error handling
+    eventSource.onerror = function() {
+        console.error('Connection to the server lost.');
+    };
+</script>
+</body>
+</html>

Templates/ServerSentEvents/.template.config/template.json

@@ -0,0 +1,14 @@
+{
+  "$schema": "http://json.schemastore.org/template",
+  "author": "genhttp.org",
+  "classifications": [ "GenHTTP", "Server Sent Events", "SSE" ],
+  "identity": "GenHTTP.Templates.ServerSentEvents",
+  "name": "GenHTTP: Server Sent Events",
+  "shortName": "genhttp-sse",
+  "sourceName": "$safeprojectname$",
+  "description": "A project template to serve a SSE event stream using the GenHTTP webserver framework",
+  "tags": {
+    "language": "C#",
+    "type": "project"
+  }
+}

Templates/ServerSentEvents/Dockerfile.linux-arm32

@@ -0,0 +1,19 @@
+FROM mcr.microsoft.com/dotnet/sdk:9.0 AS build
+WORKDIR /source
+
+# copy csproj and restore as distinct layers
+COPY $safeprojectname$/*.csproj .
+RUN dotnet restore -r linux-arm
+
+# copy and publish app and libraries
+COPY $safeprojectname$/ .
+RUN dotnet publish -c release -o /app -r linux-arm --no-restore /p:PublishTrimmed=true /p:TrimMode=Link
+
+# final stage/image
+FROM mcr.microsoft.com/dotnet/runtime-deps:9.0-alpine-arm32v7
+WORKDIR /app
+COPY --from=build /app .
+
+ENTRYPOINT ["./$safeprojectname$"]
+
+EXPOSE 8080

Templates/ServerSentEvents/Dockerfile.linux-arm64

@@ -0,0 +1,19 @@
+FROM mcr.microsoft.com/dotnet/sdk:9.0 AS build
+WORKDIR /source
+
+# copy csproj and restore as distinct layers
+COPY $safeprojectname$/*.csproj .
+RUN dotnet restore -r linux-arm64
+
+# copy and publish app and libraries
+COPY $safeprojectname$/ .
+RUN dotnet publish -c release -o /app -r linux-arm64 --no-restore /p:PublishTrimmed=true /p:TrimMode=Link
+
+# final stage/image
+FROM mcr.microsoft.com/dotnet/runtime-deps:9.0-alpine-arm64v8
+WORKDIR /app
+COPY --from=build /app .
+
+ENTRYPOINT ["./$safeprojectname$"]
+
+EXPOSE 8080

Templates/ServerSentEvents/Dockerfile.linux-x64

@@ -0,0 +1,19 @@
+FROM mcr.microsoft.com/dotnet/sdk:9.0-alpine AS build
+WORKDIR /source
+
+# copy csproj and restore as distinct layers
+COPY $safeprojectname$/*.csproj .
+RUN dotnet restore -r linux-musl-x64
+
+# copy and publish app and libraries
+COPY $safeprojectname$/ .
+RUN dotnet publish -c release -o /app -r linux-musl-x64 --no-restore /p:PublishTrimmed=true /p:TrimMode=Link
+
+# final stage/image
+FROM mcr.microsoft.com/dotnet/runtime-deps:9.0-alpine
+WORKDIR /app
+COPY --from=build /app .
+
+ENTRYPOINT ["./$safeprojectname$"]
+
+EXPOSE 8080

Templates/ServerSentEvents/README.md

@@ -0,0 +1,33 @@
+# $safeprojectname$
+
+*Add your project description here.*
+
+## Development
+
+To build this project from source, checkout this repository and execute
+the following commands in your terminal. This requires the
+[.NET SDK](https://dotnet.microsoft.com/download) to be installed.
+
+```
+cd $safeprojectname$
+dotnet run
+```
+
+This will make the service available at http://localhost:8080/.
+
+## Deployment
+
+To run this project with [Docker](https://www.docker.com/), run the 
+following commands in your terminal (and adjust the first line
+depending on your platform).
+
+```
+docker build -f Dockerfile.linux-x64 -t $safeprojectname$ .
+
+docker run -p 8080:8080 $safeprojectname$
+```
+
+## About
+
+This project uses the [GenHTTP webserver](https://genhttp.org/) to
+implement its functionality.