MCP server at POST /mcp (official SDK, stateless Streamable HTTP) (#11)

src/mesh/mcp.controller.spec.ts

@@ -0,0 +1,263 @@
+import { Client } from '@modelcontextprotocol/sdk/client/index.js';
+import { InMemoryTransport } from '@modelcontextprotocol/sdk/inMemory.js';
+import type * as net from 'node:net';
+import { describe, expect, it } from 'vitest';
+import { BROADCAST_ADDR } from './codec.js';
+import {
+  KAMIL_NUM,
+  kamilNodeInfo,
+  nodeInfoFrame,
+  startBridge,
+  waitFor,
+} from './fake-bridge.js';
+import { createMeshMcpServer } from './mcp.controller.js';
+import { MeshService } from './mesh.service.js';
+
+// callTool returns CallToolResult | a legacy compatibility shape; we only ever get the former
+type ToolOutcome = { content: { type: string; text?: string }[] };
+
+function toolText(r: Awaited<ReturnType<Client['callTool']>>): string {
+  const c = (r as ToolOutcome).content[0];
+  if (!c || c.type !== 'text') throw new Error('expected a text content block');
+  return c.text ?? '';
+}
+
+async function connectedService(): Promise<{
+  svc: MeshService;
+  sockets: net.Socket[];
+  close: () => void;
+}> {
+  const bridge = await startBridge();
+  process.env.MESH_HOST = '127.0.0.1';
+  process.env.MESH_PORT = String(bridge.port);
+  const svc = new MeshService();
+  svc.onModuleInit();
+  await waitFor(() => bridge.sockets.length === 1 && svc.status().connected);
+  return {
+    svc,
+    sockets: bridge.sockets,
+    close: () => {
+      svc.onModuleDestroy();
+      bridge.close();
+    },
+  };
+}
+
+// Drive the MCP server over an in-memory transport pair (no HTTP involved)
+async function connectMcp(svc: MeshService): Promise<{
+  client: Client;
+  close: () => Promise<void>;
+}> {
+  const [clientTransport, serverTransport] =
+    InMemoryTransport.createLinkedPair();
+  const server = createMeshMcpServer(svc);
+  await server.connect(serverTransport);
+  const client = new Client({ name: 'mesh-bot-test', version: '0.0.0' });
+  await client.connect(clientTransport);
+  return {
+    client,
+    close: async () => {
+      await client.close();
+      await server.close();
+    },
+  };
+}
+
+describe('MCP server tools', () => {
+  it('lists all six tools with descriptions and input schemas', async () => {
+    const env = await connectedService();
+    try {
+      const mcp = await connectMcp(env.svc);
+      try {
+        const { tools } = await mcp.client.listTools();
+        expect(tools.map((t) => t.name).sort()).toEqual([
+          'get_messages',
+          'get_node',
+          'list_channels',
+          'list_nodes',
+          'mesh_status',
+          'send_message',
+        ]);
+        for (const t of tools) expect(t.description?.length).toBeGreaterThan(0);
+
+        const send = tools.find((t) => t.name === 'send_message')!;
+        expect(send.inputSchema.required).toEqual(['text']);
+        expect(Object.keys(send.inputSchema.properties ?? {})).toEqual([
+          'text',
+          'to',
+        ]);
+      } finally {
+        await mcp.close();
+      }
+    } finally {
+      env.close();
+    }
+  });
+
+  it('mesh_status returns the bridge connection state', async () => {
+    const env = await connectedService();
+    try {
+      const mcp = await connectMcp(env.svc);
+      try {
+        const r = await mcp.client.callTool({
+          name: 'mesh_status',
+          arguments: {},
+        });
+        expect(r.isError).not.toBe(true);
+        expect(JSON.parse(toolText(r))).toEqual({
+          connected: true,
+          myNodeNum: null,
+          host: '127.0.0.1',
+          port: Number(process.env.MESH_PORT),
+        });
+      } finally {
+        await mcp.close();
+      }
+    } finally {
+      env.close();
+    }
+  });
+
+  it('send_message broadcasts by default and resolves names to node numbers', async () => {
+    const env = await connectedService();
+    try {
+      env.sockets[0].write(nodeInfoFrame(KAMIL_NUM, kamilNodeInfo()));
+      await waitFor(async () => (await env.svc.nodes()).length === 1);
+
+      const mcp = await connectMcp(env.svc);
+      try {
+        const r1 = await mcp.client.callTool({
+          name: 'send_message',
+          arguments: { text: 'hello' },
+        });
+        expect(r1.isError).not.toBe(true);
+        const bcast = JSON.parse(toolText(r1)) as { id: number };
+        expect(bcast.id).toBeGreaterThan(0);
+        expect(env.svc.messages()[0]).toMatchObject({
+          dir: 'tx',
+          to: BROADCAST_ADDR,
+        });
+
+        // name lookup via the node DB (unique substring)
+        const r2 = await mcp.client.callTool({
+          name: 'send_message',
+          arguments: { text: 'dm', to: 'kamil' },
+        });
+        expect(r2.isError).not.toBe(true);
+        expect(env.svc.messages()[0]).toMatchObject({
+          dir: 'tx',
+          to: KAMIL_NUM,
+        });
+      } finally {
+        await mcp.close();
+      }
+    } finally {
+      env.close();
+    }
+  });
+
+  it('send_message surfaces resolution errors as tool errors with the REST messages', async () => {
+    const env = await connectedService();
+    try {
+      const mcp = await connectMcp(env.svc);
+      try {
+        const r1 = await mcp.client.callTool({
+          name: 'send_message',
+          arguments: { text: 'x', to: 'zzz-nope' },
+        });
+        expect(r1.isError).toBe(true);
+        expect(toolText(r1)).toContain("no node matching 'zzz-nope'");
+
+        const r2 = await mcp.client.callTool({
+          name: 'send_message',
+          arguments: { text: 'x', to: '0' },
+        });
+        expect(r2.isError).toBe(true);
+        expect(toolText(r2)).toContain('invalid node number');
+      } finally {
+        await mcp.close();
+      }
+    } finally {
+      env.close();
+    }
+  });
+
+  it('get_node resolves by name and errors when missing', async () => {
+    const env = await connectedService();
+    try {
+      env.sockets[0].write(nodeInfoFrame(KAMIL_NUM, kamilNodeInfo()));
+      await waitFor(async () => (await env.svc.nodes()).length === 1);
+
+      const mcp = await connectMcp(env.svc);
+      try {
+        const r1 = await mcp.client.callTool({
+          name: 'get_node',
+          arguments: { id: 'kamil' },
+        });
+        expect(r1.isError).not.toBe(true);
+        expect(JSON.parse(toolText(r1))).toMatchObject({
+          num: KAMIL_NUM,
+          longName: 'Kamil SP8MK/P',
+          shortName: 'KK',
+        });
+
+        const r2 = await mcp.client.callTool({
+          name: 'get_node',
+          arguments: { id: 'zzz' },
+        });
+        expect(r2.isError).toBe(true);
+        expect(toolText(r2)).toContain("no node matching 'zzz'");
+      } finally {
+        await mcp.close();
+      }
+    } finally {
+      env.close();
+    }
+  });
+
+  it('list_channels, list_nodes and get_messages return the service data', async () => {
+    const env = await connectedService();
+    try {
+      env.sockets[0].write(nodeInfoFrame(KAMIL_NUM, kamilNodeInfo()));
+      await waitFor(async () => (await env.svc.nodes()).length === 1);
+
+      const mcp = await connectMcp(env.svc);
+      try {
+        expect(
+          JSON.parse(
+            toolText(
+              await mcp.client.callTool({
+                name: 'list_channels',
+                arguments: {},
+              }),
+            ),
+          ),
+        ).toEqual([]); // no channel frames fed yet
+
+        const nodes = JSON.parse(
+          toolText(
+            await mcp.client.callTool({ name: 'list_nodes', arguments: {} }),
+          ),
+        ) as { num: number; longName?: string }[];
+        expect(nodes).toHaveLength(1);
+        expect(nodes[0].num).toBe(KAMIL_NUM);
+        expect(nodes[0].longName).toBe('Kamil SP8MK/P');
+
+        await mcp.client.callTool({
+          name: 'send_message',
+          arguments: { text: 'hi' },
+        });
+        const msgs = JSON.parse(
+          toolText(
+            await mcp.client.callTool({ name: 'get_messages', arguments: {} }),
+          ),
+        ) as { dir: string; to?: number }[];
+        expect(msgs[0]).toMatchObject({ dir: 'tx', to: BROADCAST_ADDR }); // newest first
+      } finally {
+        await mcp.close();
+      }
+    } finally {
+      env.close();
+    }
+  });
+});