initial copy

s8n-runtime/WorkflowEditApiChannel.cs

@@ -0,0 +1,57 @@
+using System.Net.ServerSentEvents;
+using System.Text.Json.Serialization;
+using System.Threading.Channels;
+
+namespace s8n_runtime;
+
+public class WorkflowEditApiChannel : WorkflowRuntimeNodeBase, IWorkflowNodeRunnable
+{
+    private WebApplication? _app;
+    public static Channel<LogServerEvent>? LogServerChannel;
+    public ushort Port { get; set; } = 3080;
+
+    public async Task OnStart(WorkflowRuntime runtime, CancellationToken cancellation)
+    {
+        var builder = WebApplication.CreateBuilder();
+        builder.WebHost.UseUrls($"http://localhost:{Port}");
+        builder.Services.AddOpenApi().ConfigureHttpJsonOptions(options =>
+        {
+            var opts = options.SerializerOptions;
+            opts.IncludeFields = true;
+            opts.DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull;
+            opts.Converters.Add(new JsonStringEnumConverter());
+        }).AddCors();
+        builder.Services.AddSingleton(LogServerChannel = Channel.CreateBounded<LogServerEvent>(new BoundedChannelOptions(10000)
+        {
+            FullMode = BoundedChannelFullMode.DropOldest
+        }));
+        _app = builder.Build();
+
+        _app.MapOpenApi();
+        _app.UseCors(policy => policy.AllowAnyOrigin());
+        _app.MapGet("/api/runtime", () => runtime);
+        _app.MapGet("/api/log", (Channel<LogServerEvent> channel) =>
+        {
+            return TypedResults.ServerSentEvents(GetEvents());
+            async IAsyncEnumerable<SseItem<LogServerEvent>> GetEvents()
+            {
+                if (channel == null) yield break;
+
+                var reader = channel.Reader;
+                while (await reader.WaitToReadAsync())
+                {
+                    if (reader.TryRead(out var message))
+                    {
+                        yield return new SseItem<LogServerEvent>(message);
+                    }
+                }
+            }
+        });
+        await _app.StartAsync(cancellation);
+    }
+
+    public async Task OnStop()
+    {
+        if (_app != null) await _app.DisposeAsync();
+    }
+}