tonysneed / Demo.HelloSignalRCore

Hello SignalR Core

Hello SignalR Core

SignalR Core Demo

First we'll create a standard 'Hello World' Web API with a Values controller.
Then we'll add SignalR for duplex communication, so that actions in the Values controller 'push' results to the client after a specific time interval.
This will enable asynchonicity, for example, using queues.

Create Web API

1. Create Server Web API

   cd server
   dotnet new webapi
   

2. Install Code Generation Tools
   • Edit server.csproj file by adding the following item group:

   <ItemGroup>
     <DotNetCliToolReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Tools" Version="2.1.0-preview1-final" />
   </ItemGroup>

   • Add the following package reference:

   <PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="2.1.1" />

   • Restore dependencies: dotnet restore
   • Build the server project: dotnet build
   • Add Customizable razor templates

   dotnet new -i "AspNetCore.WebApi.Templates::*"
   dotnet new webapi-templates
   

3. Update ValuesController
   • Add new ValuesController

   dotnet aspnet-codegenerator controller -name Values -api -actions -outDir Controllers -f
   

4. Run the Web API

   dotnet run
   

   • Browse to https://localhost:5001/api/values

Add SignalR Core

1. Update ConfigureServices method in the Startup class

   services.AddSignalR();

2. Update Configure method.

   app.UseSignalR((options) => {
       options.MapHub<ValuesHub>("/Hubs/Values");
   });

3. Create Hubs folder and add IValuesClient.cs

   public interface IValuesClient
   {
       Task Get(string message);
   }

4. Add ValuesHub.cs to Hubs folder

   public class ValuesHub : Hub<IValuesClient>
   {
       public async Task Get(string message)
       {
           await Clients.Caller.Get(message);
       }
   }

5. Remove all methods accept second Get method, then refactor Get method to accept a message parameter from the URI.

   // GET: api/Values/message
   [HttpGet("{message}")]
   public IActionResult Get(string message)
   {
       return Ok(message);
   }