init server

Author: ashwin-ant

server/package.json

@@ -6,18 +6,19 @@
   "scripts": {
     "build": "tsc",
     "start": "node build/index.js",
-    "dev": "tsx watch --clear-screen=false src/index.ts",
-    "update:mcp": "git subtree pull --prefix=packages/mcp-typescript https://github.com/modelcontextprotocol/typescript-sdk.git main --squash"
+    "dev": "tsx watch --clear-screen=false src/index.ts"
   },
   "devDependencies": {
     "@types/eventsource": "^1.1.15",
     "@types/express": "^4.17.21",
+    "@types/ws": "^8.5.12",
     "eventsource": "^2.0.2",
     "tsx": "^4.19.0",
     "typescript": "^5.6.2"
   },
   "dependencies": {
-    "express": "^4.20.0",
-    "mcp-typescript": "file:packages/mcp-typescript"
+    "express": "^4.21.0",
+    "mcp-typescript": "file:../packages/mcp-typescript",
+    "ws": "^8.18.0"
   }
 }

server/src/client.ts

@@ -0,0 +1,74 @@
+import { Client } from "mcp-typescript/client/index.js";
+import { SSEClientTransport } from "mcp-typescript/client/sse.js";
+import { StdioClientTransport } from "mcp-typescript/client/stdio.js";
+import {
+  ListResourcesResult,
+  ReadResourceResult,
+  ListResourcesResultSchema,
+  ReadResourceResultSchema,
+} from "mcp-typescript/types.js";
+
+export class McpClient {
+  private client: Client;
+  private transport?: SSEClientTransport | StdioClientTransport;
+
+  constructor(name: string, version: string) {
+    this.client = new Client({
+      name,
+      version,
+    });
+  }
+
+  async connect(url: string | URL) {
+    const urlObj = typeof url === "string" ? new URL(url) : url;
+
+    if (urlObj.protocol === "http:" || urlObj.protocol === "https:") {
+      this.transport = new SSEClientTransport();
+    } else {
+      throw new Error(`Unsupported protocol: ${urlObj.protocol}`);
+    }
+
+    await this.transport.connect(urlObj);
+    await this.client.connect(this.transport);
+  }
+
+  async connectStdio(command: string, args: string[] = []) {
+    this.transport = new StdioClientTransport();
+    await this.transport.spawn({ command, args });
+    await this.client.connect(this.transport);
+  }
+
+  async close() {
+    await this.client.close();
+  }
+
+  // Resource Operations
+  async listResources(): Promise<ListResourcesResult> {
+    return await this.client.request(
+      {
+        method: "resources/list",
+      },
+      ListResourcesResultSchema,
+    );
+  }
+
+  async readResource(uri: string): Promise<ReadResourceResult> {
+    return await this.client.request(
+      {
+        method: "resources/read",
+        params: { uri },
+      },
+      ReadResourceResultSchema,
+    );
+  }
+
+  getServerCapabilities() {
+    return this.client.getServerCapabilities();
+  }
+
+  getServerVersion() {
+    return this.client.getServerVersion();
+  }
+}
+
+export default McpClient;

server/src/index.ts

@@ -0,0 +1,45 @@
+import McpClient from "./client.js";
+import express from "express";
+import http from "http";
+import { WebSocket, WebSocketServer } from "ws";
+
+const app = express();
+const server = http.createServer(app);
+const wss = new WebSocketServer({ server });
+
+// Create and connect the MCP client
+const mcpClient = new McpClient("MyApp", "1.0.0");
+await mcpClient.connectStdio(
+  "/Users/ashwin/.nvm/versions/node/v18.20.4/bin/node",
+  ["/Users/ashwin/code/example-servers/build/everything/index.js"],
+);
+
+wss.on("connection", (ws: WebSocket) => {
+  ws.on("message", async (message: string) => {
+    try {
+      const command = JSON.parse(message);
+
+      if (command.type === "listResources") {
+        const resources = await mcpClient.listResources();
+        ws.send(JSON.stringify({ type: "resources", data: resources }));
+      } else if (command.type === "readResource" && command.uri) {
+        const resource = await mcpClient.readResource(command.uri);
+        ws.send(JSON.stringify({ type: "resource", data: resource }));
+      }
+    } catch (error) {
+      console.error("Error:", error);
+      ws.send(JSON.stringify({ type: "error", message: String(error) }));
+    }
+  });
+});
+
+const PORT = process.env.PORT || 3000;
+server.listen(PORT, () => {
+  console.log(`Server is running on port ${PORT}`);
+});
+
+// Close the client when the server is shutting down
+process.on("SIGINT", async () => {
+  await mcpClient.close();
+  process.exit();
+});

server/tsconfig.json

@@ -0,0 +1,16 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "Node16",
+    "moduleResolution": "Node16",
+    "outDir": "./build",
+    "rootDir": "./src",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "resolveJsonModule": true
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "packages", "**/*.spec.ts"]
+}