feat(gateway): add optional bonjour/mdns discovery

src/gateway/server.discovery.test.ts

@@ -0,0 +1,76 @@
+import { describe, it, expect, beforeAll, beforeEach, vi } from 'vitest';
+
+const startDiscoveryMock = vi.fn();
+const stopDiscoveryMock = vi.fn();
+
+vi.mock('./discovery.js', () => ({
+  startGatewayDiscovery: startDiscoveryMock,
+}));
+
+describe('GatewayServer discovery lifecycle', () => {
+  let GatewayServer: typeof import('./server.js').GatewayServer;
+  let server: import('./server.js').GatewayServer;
+
+  const baseConfig = {
+    port: 18910,
+    host: '0.0.0.0',
+    sessionManager: {
+      getSession: () => ({ id: 's1', addMessage: () => {}, getHistory: () => [], clear: () => {}, setHistory: () => {}, replaceHistory: () => {} }),
+      listSessions: () => [],
+    } as unknown as import('./server.js').GatewayServerConfig['sessionManager'],
+    modelClient: { chat: async () => ({ content: 'ok', usage: { inputTokens: 0, outputTokens: 0 }, stopReason: 'end_turn' }) },
+    systemPrompt: 'test',
+    toolRegistry: {
+      list: () => [],
+      get: () => undefined,
+    } as unknown as import('./server.js').GatewayServerConfig['toolRegistry'],
+    toolExecutor: { execute: async () => ({ success: true, output: '' }) } as unknown as import('./server.js').GatewayServerConfig['toolExecutor'],
+    version: '0.1.0-test',
+  } as const;
+
+  beforeAll(async () => {
+    ({ GatewayServer } = await import('./server.js'));
+  });
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    startDiscoveryMock.mockResolvedValue({
+      stop: stopDiscoveryMock,
+    });
+    server = new GatewayServer({
+      ...baseConfig,
+      discovery: {
+        enabled: true,
+        serviceName: 'flynn-test',
+        serviceType: '_flynn._tcp',
+        txtRecord: { env: 'test' },
+      },
+    });
+  });
+
+  it('starts and stops discovery when enabled', async () => {
+    const typedServer = server as unknown as { startDiscovery: (host: string, port: number) => Promise<void> };
+    await typedServer.startDiscovery('0.0.0.0', 18910);
+    await server.stop();
+
+    expect(startDiscoveryMock).toHaveBeenCalledOnce();
+    const [callConfig] = startDiscoveryMock.mock.calls[0] as [Record<string, unknown>];
+    expect(callConfig.serviceName).toBe('flynn-test');
+    expect(callConfig.serviceType).toBe('_flynn._tcp');
+    expect(callConfig.port).toBe(18910);
+    expect(callConfig.txtRecord).toMatchObject({
+      env: 'test',
+      version: '0.1.0-test',
+    });
+    expect(stopDiscoveryMock).toHaveBeenCalledOnce();
+  });
+
+  it('does not advertise when host is loopback', async () => {
+    const typedServer = server as unknown as { startDiscovery: (host: string, port: number) => Promise<void> };
+    await typedServer.startDiscovery('127.0.0.1', 18911);
+    await server.stop();
+
+    expect(startDiscoveryMock).not.toHaveBeenCalled();
+    expect(stopDiscoveryMock).not.toHaveBeenCalled();
+  });
+});