Merge pull request #73 from decocms/fix/sse-bun-serve

fix bun serve

Author: tlgimenes

bun.lock

@@ -341,6 +341,7 @@
       "version": "1.0.0",
       "devDependencies": {
         "@decocms/runtime": "0.25.1",
+        "@types/bun": "^1.2.14",
         "vite": "7.2.0",
         "zod": "^3.24.3",
       },

mcp-studio/server/main.ts

@@ -6,6 +6,7 @@
  */
 
 import { type DefaultEnv, withRuntime } from "@decocms/runtime";
+import { serve } from "@decocms/mcps-shared/serve";
 import {
   type Env as DecoEnv,
   Scopes,
@@ -65,4 +66,4 @@ const runtime = withRuntime<Env, typeof StateSchema>({
   ],
 });
 
-export default runtime;
+serve(runtime.fetch);

meta-ads/server/main.ts

@@ -12,6 +12,7 @@
  */
 import { readFileSync } from "fs";
 import { type DefaultEnv, withRuntime } from "@decocms/runtime";
+import { serve } from "@decocms/mcps-shared/serve";
 
 import { tools } from "./tools/index.ts";
 import { META_API_VERSION, META_ADS_SCOPES, META_APP_ID } from "./constants.ts";
@@ -216,4 +217,4 @@ const runtime = withRuntime<Env>({
   tools,
 });
 
-export default runtime;
+serve(runtime.fetch);

openrouter/server/main.ts

@@ -8,6 +8,7 @@
  * with built-in fallback mechanisms, cost optimization, and provider routing.
  */
 import { type DefaultEnv, withRuntime } from "@decocms/runtime";
+import { serve } from "@decocms/mcps-shared/serve";
 
 import { tools } from "./tools/index.ts";
 
@@ -60,4 +61,4 @@ const runtime = withRuntime<Env>({
   tools,
 });
 
-export default runtime;
+serve(runtime.fetch);

registry/server/main.ts

@@ -5,6 +5,7 @@
  */
 
 import { type DefaultEnv, withRuntime } from "@decocms/runtime";
+import { serve } from "@decocms/mcps-shared/serve";
 import {
   type Env as DecoEnv,
   StateSchema as BaseStateSchema,
@@ -81,13 +82,9 @@ const runtime = withRuntime<Env, typeof StateSchema>({
   },
 });
 
-const server = {
-  fetch: (req: Request) => {
-    if (new URL(req.url).pathname === "/_healthcheck") {
-      return new Response("OK", { status: 200 });
-    }
-    return runtime.fetch(req, { ...process.env } as Env, {});
-  },
-};
-
-export default server;
+serve((req: Request) => {
+  if (new URL(req.url).pathname === "/_healthcheck") {
+    return new Response("OK", { status: 200 });
+  }
+  return runtime.fetch(req, { ...process.env } as Env, {});
+});

shared/package.json

@@ -16,9 +16,11 @@
         "./video-generators": "./video-generators/index.ts",
         "./audio-transcribers": "./audio-transcribers/index.ts",
         "./storage": "./storage/index.ts",
-        "./search-ai": "./search-ai/index.ts"
+        "./search-ai": "./search-ai/index.ts",
+        "./serve": "./serve.ts"
     },
     "devDependencies": {
+        "@types/bun": "^1.2.14",
         "vite": "7.2.0",
         "@decocms/runtime": "0.25.1",
         "zod": "^3.24.3"

shared/serve.ts

@@ -0,0 +1,35 @@
+/// <reference types="bun" />
+
+/**
+ * Shared Bun.serve utility for MCP servers
+ *
+ * This utility provides a consistent way to serve MCP applications
+ * with the correct configuration for SSE endpoints and K8s compatibility.
+ */
+
+// Using 'any' for additional args to support both simple fetch handlers
+// and runtime.fetch which expects (req, env, ctx)
+// biome-ignore lint/suspicious/noExplicitAny: Required for compatibility with runtime.fetch signature
+type Fetcher = (req: Request, ...args: any[]) => Response | Promise<Response>;
+
+/**
+ * Starts a Bun server with the provided fetch handler.
+ *
+ * Configures the server with:
+ * - idleTimeout: 0 (required for SSE endpoints like notifications)
+ * - hostname: 0.0.0.0 (required for K8s)
+ * - port: process.env.PORT or 8001
+ * - development mode based on NODE_ENV
+ *
+ * @param fetcher - The fetch handler function
+ */
+export function serve(fetcher: Fetcher) {
+  Bun.serve({
+    // This was necessary because MCP has SSE endpoints (like notification) that disconnects after 10 seconds (default bun idle timeout)
+    idleTimeout: 0,
+    port: process.env.PORT || 8001,
+    hostname: "0.0.0.0", // Listen on all network interfaces (required for K8s)
+    fetch: fetcher,
+    development: process.env.NODE_ENV !== "production",
+  });
+}