Convert MCP server to be a stdio server for demo simplicity

Author: mikesir87

package-lock.json

@@ -14,7 +14,6 @@
   "description": "",
   "dependencies": {
     "@modelcontextprotocol/sdk": "^1.17.5",
-    "express": "^5.1.0",
     "node-fetch": "^3.3.2"
   },
   "devDependencies": {

package.json

@@ -2,11 +2,20 @@
   "$schema": "https://static.modelcontextprotocol.io/schemas/2025-07-09/server.schema.json",
   "name": "io.github.dockersamples/mcp-docker-release-information", 
   "description": "MCP server providing Docker Desktop release notes and security information.",
+  "status": "active",
+  "repository": {
+    "source": "github",
+    "url": "https://github.com/dockersamples/mcp-docker-release-information"
+  },
+  "version": "1.0.0",
   "packages": [
     {
       "registry_type": "oci",
       "identifier": "dockersamples/mcp-docker-release-information",
-      "version": "1.0.0"
+      "version": "1.0.0",
+      "transport": {
+        "type": "stdio"
+      }
     }
   ]
 }

server.json

@@ -1,180 +1,78 @@
-import express from "express";
 import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
 import { z } from "zod";
 import { parseReleases, parseSecurityAnnouncements } from "./util.js";
 import fetch from "node-fetch";
-import { SSEServerTransport } from "@modelcontextprotocol/sdk/server/sse.js";
+import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
 
-function getServer() {
-  const server = new McpServer({
-    name: "demo-server",
-    version: "1.0.0",
-  });
-
-  server.registerTool(
-    "get-desktop-releases",
-    {
-      title: "Get Docker Desktop Release Notes",
-      description: "Get information about the latest Docker Desktop releases",
-      inputSchema: {
-        limit: z
-          .number()
-          .min(1)
-          .max(10)
-          .default(6)
-          .optional()
-          .describe("Number of releases to return"),
-      },
-    },
-    async ({ limit = 6 }) => {
-      const data = (
-        await fetch("https://docs.docker.com/desktop/release-notes/index.md")
-      ).text();
-
-      return {
-        content: [
-          {
-            type: "text",
-            text: parseReleases(await data, limit),
-          },
-        ],
-      };
-    },
-  );
+const server = new McpServer({
+  name: "demo-server",
+  version: "1.0.0",
+});
 
-  server.registerTool(
-    "get-security-details",
-    {
-      title: "Get Docker Desktop Security Details",
-      description:
-        "Get information about the latest Docker Desktop security updates",
-      inputSchema: {
-        limit: z
-          .number()
-          .min(1)
-          .max(10)
-          .default(6)
-          .optional()
-          .describe("Number of security updates to return"),
-      },
+server.registerTool(
+  "get-desktop-releases",
+  {
+    title: "Get Docker Desktop Release Notes",
+    description: "Get information about the latest Docker Desktop releases",
+    inputSchema: {
+      limit: z
+        .number()
+        .min(1)
+        .max(10)
+        .default(6)
+        .optional()
+        .describe("Number of releases to return"),
     },
-    async ({ limit = 6 }) => {
-      const data = (
-        await fetch(
-          "https://docs.docker.com/security/security-announcements/index.md",
-        )
-      ).text();
-
-      return {
-        content: [
-          {
-            type: "text",
-            text: parseSecurityAnnouncements(await data, limit),
-          },
-        ],
-      };
+  },
+  async ({ limit = 6 }) => {
+    const data = (
+      await fetch("https://docs.docker.com/desktop/release-notes/index.md")
+    ).text();
+
+    return {
+      content: [
+        {
+          type: "text",
+          text: parseReleases(await data, limit),
+        },
+      ],
+    };
+  },
+);
+
+server.registerTool(
+  "get-security-details",
+  {
+    title: "Get Docker Desktop Security Details",
+    description:
+      "Get information about the latest Docker Desktop security updates",
+    inputSchema: {
+      limit: z
+        .number()
+        .min(1)
+        .max(10)
+        .default(6)
+        .optional()
+        .describe("Number of security updates to return"),
     },
-  );
-
-  return server;
-}
-
-const app = express();
-app.use(express.json());
-
-// Store transports by session ID
-const transports = {};
-
-// SSE endpoint for establishing the stream
-app.get("/mcp", async (req, res) => {
-  console.log("Received GET request to /sse (establishing SSE stream)");
-
-  try {
-    // Create a new SSE transport for the client
-    // The endpoint for POST messages is '/messages'
-    const transport = new SSEServerTransport("/messages", res);
-
-    // Store the transport by session ID
-    const sessionId = transport.sessionId;
-    transports[sessionId] = transport;
-
-    // Set up onclose handler to clean up transport when closed
-    transport.onclose = () => {
-      console.log(`SSE transport closed for session ${sessionId}`);
-      delete transports[sessionId];
+  },
+  async ({ limit = 6 }) => {
+    const data = (
+      await fetch(
+        "https://docs.docker.com/security/security-announcements/index.md",
+      )
+    ).text();
+
+    return {
+      content: [
+        {
+          type: "text",
+          text: parseSecurityAnnouncements(await data, limit),
+        },
+      ],
     };
+  },
+);
 
-    // Connect the transport to the MCP server
-    const server = getServer();
-    await server.connect(transport);
-
-    console.log(`Established SSE stream with session ID: ${sessionId}`);
-  } catch (error) {
-    console.error("Error establishing SSE stream:", error);
-    if (!res.headersSent) {
-      res.status(500).send("Error establishing SSE stream");
-    }
-  }
-});
-
-// Messages endpoint for receiving client JSON-RPC requests
-app.post("/messages", async (req, res) => {
-  console.log("Received POST request to /messages");
-
-  // Extract session ID from URL query parameter
-  // In the SSE protocol, this is added by the client based on the endpoint event
-  const sessionId = req.query.sessionId;
-
-  if (!sessionId) {
-    console.error("No session ID provided in request URL");
-    res.status(400).send("Missing sessionId parameter");
-    return;
-  }
-
-  const transport = transports[sessionId];
-  if (!transport) {
-    console.error(`No active transport found for session ID: ${sessionId}`);
-    res.status(404).send("Session not found");
-    return;
-  }
-
-  try {
-    // Handle the POST message with the transport
-    await transport.handlePostMessage(req, res, req.body);
-  } catch (error) {
-    console.error("Error handling request:", error);
-    if (!res.headersSent) {
-      res.status(500).send("Error handling request");
-    }
-  }
-});
-
-// Start the server
-const PORT = 3000;
-app.listen(PORT, (error) => {
-  if (error) {
-    console.error("Failed to start server:", error);
-    process.exit(1);
-  }
-  console.log(
-    `Simple SSE Server (deprecated protocol version 2024-11-05) listening on port ${PORT}`,
-  );
-});
-
-// Handle server shutdown
-process.on("SIGINT", async () => {
-  console.log("Shutting down server...");
-
-  // Close all active transports to properly clean up resources
-  for (const sessionId in transports) {
-    try {
-      console.log(`Closing transport for session ${sessionId}`);
-      await transports[sessionId].close();
-      delete transports[sessionId];
-    } catch (error) {
-      console.error(`Error closing transport for session ${sessionId}:`, error);
-    }
-  }
-  console.log("Server shutdown complete");
-  process.exit(0);
-});
+const transport = new StdioServerTransport();
+await server.connect(transport);