Implement start of WebSocket support

src/Universalis.Application/Controllers/V2/WebSocketController.cs

@@ -0,0 +1,66 @@
+using Microsoft.AspNetCore.Mvc;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
+using Universalis.Application.Realtime;
+using Universalis.Application.Swagger;
+using Universalis.Application.Views.V2.Realtime;
+
+namespace Universalis.Application.Controllers.V2;
+
+[ApiController]
+[ApiVersion("1")]
+[ApiVersion("2")]
+[Route("api")]
+public class WebSocketController : ControllerBase
+{
+    private readonly ISocketProcessor _socketProcessor;
+
+    public WebSocketController(ISocketProcessor socketProcessor)
+    {
+        _socketProcessor = socketProcessor;
+    }
+
+    /// <summary>
+    /// Connect to the WebSocket endpoint of the API. Requires a valid WebSocket client.
+    /// </summary>
+    [HttpGet]
+    [MapToApiVersion("1")]
+    [Route("ws")]
+    [ApiTag("WebSocket")]
+    public Task<IActionResult> Get(CancellationToken cancellationToken = default)
+    {
+        return GetV2(cancellationToken);
+    }
+
+    /// <summary>
+    /// Connect to the WebSocket endpoint of the API. Requires a valid WebSocket client.
+    /// </summary>
+    [HttpGet]
+    [MapToApiVersion("2")]
+    [Route("v{version:apiVersion}/ws")]
+    [ApiTag("WebSocket")]
+    public async Task<IActionResult> GetV2(CancellationToken cancellationToken = default)
+    {
+        if (HttpContext.WebSockets.IsWebSocketRequest)
+        {
+            using var webSocket = await HttpContext.WebSockets.AcceptWebSocketAsync(
+                new WebSocketAcceptContext { DangerousEnableCompression = true });
+            var socketFinished = new TaskCompletionSource<WebSocketCompletionResult>();
+
+            _ = _socketProcessor.AddSocket(webSocket, socketFinished);
+
+            var result = await socketFinished.Task;
+
+            return Ok(new WebSocketCompletionView
+            {
+                Error = result.Error,
+                Reason = result.Reason,
+            });
+        }
+        else
+        {
+            return BadRequest();
+        }
+    }
+}

src/Universalis.Application/Realtime/ISocketProcessor.cs

@@ -0,0 +1,9 @@
+using System.Net.WebSockets;
+using System.Threading.Tasks;
+
+namespace Universalis.Application.Realtime;
+
+public interface ISocketProcessor
+{
+    Task AddSocket(WebSocket ws, TaskCompletionSource<WebSocketCompletionResult> cs);
+}

src/Universalis.Application/Realtime/SocketProcessor.cs

@@ -0,0 +1,18 @@
+using System.Net.WebSockets;
+using System.Threading.Tasks;
+
+namespace Universalis.Application.Realtime;
+
+public class SocketProcessor : ISocketProcessor
+{
+    public Task AddSocket(WebSocket ws, TaskCompletionSource<WebSocketCompletionResult> cs)
+    {
+        cs.SetResult(new WebSocketCompletionResult
+        {
+            Error = false,
+            Reason = "",
+        });
+
+        return Task.CompletedTask;
+    }
+}

src/Universalis.Application/Realtime/WebSocketCompletionResult.cs

@@ -0,0 +1,8 @@
+namespace Universalis.Application.Realtime;
+
+public class WebSocketCompletionResult
+{
+    public bool Error { get; init; }
+
+    public string Reason { get; init; }
+}

src/Universalis.Application/Startup.cs

@@ -14,12 +14,10 @@
 using System.Linq;
 using System.Reflection;
 using System.Xml.XPath;
-using Microsoft.AspNetCore.Hosting.StaticWebAssets;
-using Microsoft.AspNetCore.StaticFiles.Infrastructure;
-using Microsoft.Extensions.FileProviders;
 using Universalis.Alerts;
 using Universalis.Application.Caching;
 using Universalis.Application.ExceptionFilters;
+using Universalis.Application.Realtime;
 using Universalis.Application.Swagger;
 using Universalis.Application.Uploads.Behaviors;
 using Universalis.Application.Views.V1;
@@ -28,7 +26,6 @@
 using Universalis.GameData;
 using Universalis.Mogboard;
 using Universalis.Mogboard.WebUI;
-using Universalis.Mogboard.WebUI.Pages;
 
 namespace Universalis.Application;
 
@@ -53,6 +50,8 @@ public void ConfigureServices(IServiceCollection services)
         var cacheSize = int.Parse(Configuration["MarketCurrentDataCacheSize"]);
         services.AddSingleton<ICache<CurrentlyShownQuery, CurrentlyShownView>>(new MemoryCache<CurrentlyShownQuery, CurrentlyShownView>(cacheSize));
 
+        services.AddSingleton<ISocketProcessor, SocketProcessor>();
+
         services
             .AddAuthentication(NegotiateDefaults.AuthenticationScheme)
             .AddNegotiate();
@@ -172,7 +171,12 @@ public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
 
             options.DocumentTitle = "Universalis Documentation";
         });
-
+
+        app.UseWebSockets(new WebSocketOptions
+        {
+            KeepAliveInterval = TimeSpan.FromMinutes(2),
+        });
+
         app.UseStaticFiles();
 
         app.UseRouting();

src/Universalis.Application/Universalis.Application.csproj

@@ -39,8 +39,4 @@
     <ProjectReference Include="..\Universalis.Mogboard\Universalis.Mogboard.csproj" />
   </ItemGroup>
 
-  <ItemGroup>
-    <Folder Include="Views\V1\" />
-  </ItemGroup>
-
 </Project>

src/Universalis.Application/Views/V2/Realtime/WebSocketCompletionView.cs

@@ -0,0 +1,18 @@
+using System.Text.Json.Serialization;
+
+namespace Universalis.Application.Views.V2.Realtime;
+
+public class WebSocketCompletionView
+{
+    /// <summary>
+    /// Whether or not the WebSocket completed in an error state.
+    /// </summary>
+    [JsonPropertyName("error")]
+    public bool Error { get; set; }
+
+    /// <summary>
+    /// The reason for the WebSocket completion.
+    /// </summary>
+    [JsonPropertyName("reason")]
+    public string Reason { get; set; }
+}