typescript-sdk/test/server/sse.test.ts
Valentin Beggi 97ab379e45
feat: add url property to RequestInfo interface (#1353)
Co-authored-by: Matt <77928207+mattzcarey@users.noreply.github.com>
2026-02-15 14:57:53 +02:00

740 lines
32 KiB
TypeScript

import http from 'node:http';
import { type Mocked } from 'vitest';
import { SSEServerTransport } from '../../src/server/sse.js';
import { McpServer } from '../../src/server/mcp.js';
import { createServer, type Server } from 'node:http';
import { CallToolResult, JSONRPCMessage } from '../../src/types.js';
import { zodTestMatrix, type ZodMatrixEntry } from '../../src/__fixtures__/zodTestMatrix.js';
import { listenOnRandomPort } from '../helpers/http.js';
const createMockResponse = () => {
const res = {
writeHead: vi.fn<http.ServerResponse['writeHead']>().mockReturnThis(),
write: vi.fn<http.ServerResponse['write']>().mockReturnThis(),
on: vi.fn<http.ServerResponse['on']>().mockReturnThis(),
end: vi.fn<http.ServerResponse['end']>().mockReturnThis()
};
return res as unknown as Mocked<http.ServerResponse>;
};
const createMockRequest = ({
headers = {},
body,
url = '/messages'
}: { headers?: Record<string, string>; body?: string; url?: string } = {}) => {
const mockReq = {
headers,
body: body ? body : undefined,
url,
auth: {
token: 'test-token'
},
on: vi.fn<http.IncomingMessage['on']>().mockImplementation((event, listener) => {
const mockListener = listener as unknown as (...args: unknown[]) => void;
if (event === 'data') {
mockListener(Buffer.from(body || '') as unknown as Error);
}
if (event === 'error') {
mockListener(new Error('test'));
}
if (event === 'end') {
mockListener();
}
if (event === 'close') {
setTimeout(listener, 100);
}
return mockReq;
}),
listeners: vi.fn<http.IncomingMessage['listeners']>(),
removeListener: vi.fn<http.IncomingMessage['removeListener']>()
} as unknown as http.IncomingMessage;
return mockReq;
};
async function readAllSSEEvents(response: Response): Promise<string[]> {
const reader = response.body?.getReader();
if (!reader) throw new Error('No readable stream');
const events: string[] = [];
const decoder = new TextDecoder();
try {
while (true) {
const { done, value } = await reader.read();
if (done) break;
if (value) {
events.push(decoder.decode(value));
}
}
} finally {
reader.releaseLock();
}
return events;
}
/**
* Helper to send JSON-RPC request
*/
async function sendSsePostRequest(
baseUrl: URL,
message: JSONRPCMessage | JSONRPCMessage[],
sessionId?: string,
extraHeaders?: Record<string, string>
): Promise<Response> {
const headers: Record<string, string> = {
'Content-Type': 'application/json',
Accept: 'application/json, text/event-stream',
...extraHeaders
};
if (sessionId) {
baseUrl.searchParams.set('sessionId', sessionId);
}
return fetch(baseUrl, {
method: 'POST',
headers,
body: JSON.stringify(message)
});
}
describe.each(zodTestMatrix)('$zodVersionLabel', (entry: ZodMatrixEntry) => {
const { z } = entry;
/**
* Helper to create and start test HTTP server with MCP setup
*/
async function createTestServerWithSse(args: { mockRes: http.ServerResponse }): Promise<{
server: Server;
transport: SSEServerTransport;
mcpServer: McpServer;
baseUrl: URL;
sessionId: string;
serverPort: number;
}> {
const mcpServer = new McpServer({ name: 'test-server', version: '1.0.0' }, { capabilities: { logging: {} } });
mcpServer.tool(
'greet',
'A simple greeting tool',
{ name: z.string().describe('Name to greet') },
async ({ name }): Promise<CallToolResult> => {
return { content: [{ type: 'text', text: `Hello, ${name}!` }] };
}
);
const endpoint = '/messages';
const transport = new SSEServerTransport(endpoint, args.mockRes);
const sessionId = transport.sessionId;
await mcpServer.connect(transport);
const server = createServer(async (req, res) => {
try {
await transport.handlePostMessage(req, res);
} catch (error) {
console.error('Error handling request:', error);
if (!res.headersSent) res.writeHead(500).end();
}
});
const baseUrl = await listenOnRandomPort(server);
const addr = server.address();
const port = typeof addr === 'string' ? new URL(baseUrl).port : (addr as any).port;
return { server, transport, mcpServer, baseUrl, sessionId, serverPort: Number(port) };
}
describe('SSEServerTransport', () => {
async function initializeServer(baseUrl: URL): Promise<void> {
const response = await sendSsePostRequest(baseUrl, {
jsonrpc: '2.0',
method: 'initialize',
params: {
clientInfo: { name: 'test-client', version: '1.0' },
protocolVersion: '2025-03-26',
capabilities: {}
},
id: 'init-1'
} as JSONRPCMessage);
expect(response.status).toBe(202);
const text = await readAllSSEEvents(response);
expect(text).toHaveLength(1);
expect(text[0]).toBe('Accepted');
}
describe('start method', () => {
it('should correctly append sessionId to a simple relative endpoint', async () => {
const mockRes = createMockResponse();
const endpoint = '/messages';
const transport = new SSEServerTransport(endpoint, mockRes);
const expectedSessionId = transport.sessionId;
await transport.start();
expect(mockRes.writeHead).toHaveBeenCalledWith(200, expect.any(Object));
expect(mockRes.write).toHaveBeenCalledTimes(1);
expect(mockRes.write).toHaveBeenCalledWith(`event: endpoint\ndata: /messages?sessionId=${expectedSessionId}\n\n`);
});
it('should correctly append sessionId to an endpoint with existing query parameters', async () => {
const mockRes = createMockResponse();
const endpoint = '/messages?foo=bar&baz=qux';
const transport = new SSEServerTransport(endpoint, mockRes);
const expectedSessionId = transport.sessionId;
await transport.start();
expect(mockRes.writeHead).toHaveBeenCalledWith(200, expect.any(Object));
expect(mockRes.write).toHaveBeenCalledTimes(1);
expect(mockRes.write).toHaveBeenCalledWith(
`event: endpoint\ndata: /messages?foo=bar&baz=qux&sessionId=${expectedSessionId}\n\n`
);
});
it('should correctly append sessionId to an endpoint with a hash fragment', async () => {
const mockRes = createMockResponse();
const endpoint = '/messages#section1';
const transport = new SSEServerTransport(endpoint, mockRes);
const expectedSessionId = transport.sessionId;
await transport.start();
expect(mockRes.writeHead).toHaveBeenCalledWith(200, expect.any(Object));
expect(mockRes.write).toHaveBeenCalledTimes(1);
expect(mockRes.write).toHaveBeenCalledWith(`event: endpoint\ndata: /messages?sessionId=${expectedSessionId}#section1\n\n`);
});
it('should correctly append sessionId to an endpoint with query parameters and a hash fragment', async () => {
const mockRes = createMockResponse();
const endpoint = '/messages?key=value#section2';
const transport = new SSEServerTransport(endpoint, mockRes);
const expectedSessionId = transport.sessionId;
await transport.start();
expect(mockRes.writeHead).toHaveBeenCalledWith(200, expect.any(Object));
expect(mockRes.write).toHaveBeenCalledTimes(1);
expect(mockRes.write).toHaveBeenCalledWith(
`event: endpoint\ndata: /messages?key=value&sessionId=${expectedSessionId}#section2\n\n`
);
});
it('should correctly handle the root path endpoint "/"', async () => {
const mockRes = createMockResponse();
const endpoint = '/';
const transport = new SSEServerTransport(endpoint, mockRes);
const expectedSessionId = transport.sessionId;
await transport.start();
expect(mockRes.writeHead).toHaveBeenCalledWith(200, expect.any(Object));
expect(mockRes.write).toHaveBeenCalledTimes(1);
expect(mockRes.write).toHaveBeenCalledWith(`event: endpoint\ndata: /?sessionId=${expectedSessionId}\n\n`);
});
it('should correctly handle an empty string endpoint ""', async () => {
const mockRes = createMockResponse();
const endpoint = '';
const transport = new SSEServerTransport(endpoint, mockRes);
const expectedSessionId = transport.sessionId;
await transport.start();
expect(mockRes.writeHead).toHaveBeenCalledWith(200, expect.any(Object));
expect(mockRes.write).toHaveBeenCalledTimes(1);
expect(mockRes.write).toHaveBeenCalledWith(`event: endpoint\ndata: /?sessionId=${expectedSessionId}\n\n`);
});
/**
* Test: Tool With Request Info
*/
it('should pass request info to tool callback', async () => {
const mockRes = createMockResponse();
const { mcpServer, baseUrl, sessionId, serverPort } = await createTestServerWithSse({ mockRes });
await initializeServer(baseUrl);
mcpServer.tool(
'test-request-info',
'A simple test tool with request info',
{ name: z.string().describe('Name to greet') },
async ({ name }, { requestInfo }): Promise<CallToolResult> => {
return {
content: [
{ type: 'text', text: `Hello, ${name}!` },
{ type: 'text', text: `${JSON.stringify(requestInfo)}` }
]
};
}
);
const toolCallMessage: JSONRPCMessage = {
jsonrpc: '2.0',
method: 'tools/call',
params: {
name: 'test-request-info',
arguments: {
name: 'Test User'
}
},
id: 'call-1'
};
const response = await sendSsePostRequest(baseUrl, toolCallMessage, sessionId);
expect(response.status).toBe(202);
expect(mockRes.write).toHaveBeenCalledWith(`event: endpoint\ndata: /messages?sessionId=${sessionId}\n\n`);
const expectedMessage = {
result: {
content: [
{
type: 'text',
text: 'Hello, Test User!'
},
{
type: 'text',
text: JSON.stringify({
headers: {
host: `127.0.0.1:${serverPort}`,
connection: 'keep-alive',
'content-type': 'application/json',
accept: 'application/json, text/event-stream',
'accept-language': '*',
'sec-fetch-mode': 'cors',
'user-agent': 'node',
'accept-encoding': 'gzip, deflate',
'content-length': '124'
},
url: `http://127.0.0.1:${serverPort}/?sessionId=${sessionId}`
})
}
]
},
jsonrpc: '2.0',
id: 'call-1'
};
expect(mockRes.write).toHaveBeenCalledWith(`event: message\ndata: ${JSON.stringify(expectedMessage)}\n\n`);
});
});
describe('handlePostMessage method', () => {
it('should return 500 if server has not started', async () => {
const mockReq = createMockRequest();
const mockRes = createMockResponse();
const endpoint = '/messages';
const transport = new SSEServerTransport(endpoint, mockRes);
const error = 'SSE connection not established';
await expect(transport.handlePostMessage(mockReq, mockRes)).rejects.toThrow(error);
expect(mockRes.writeHead).toHaveBeenCalledWith(500);
expect(mockRes.end).toHaveBeenCalledWith(error);
});
it('should return 400 if content-type is not application/json', async () => {
const mockReq = createMockRequest({ headers: { 'content-type': 'text/plain' } });
const mockRes = createMockResponse();
const endpoint = '/messages';
const transport = new SSEServerTransport(endpoint, mockRes);
await transport.start();
transport.onerror = vi.fn();
const error = 'Unsupported content-type: text/plain';
await expect(transport.handlePostMessage(mockReq, mockRes)).resolves.toBe(undefined);
expect(mockRes.writeHead).toHaveBeenCalledWith(400);
expect(mockRes.end).toHaveBeenCalledWith(expect.stringContaining(error));
expect(transport.onerror).toHaveBeenCalledWith(new Error(error));
});
it('should return 400 if message has not a valid schema', async () => {
const invalidMessage = JSON.stringify({
// missing jsonrpc field
method: 'call',
params: [1, 2, 3],
id: 1
});
const mockReq = createMockRequest({
headers: { 'content-type': 'application/json' },
body: invalidMessage
});
const mockRes = createMockResponse();
const endpoint = '/messages';
const transport = new SSEServerTransport(endpoint, mockRes);
await transport.start();
transport.onmessage = vi.fn();
await transport.handlePostMessage(mockReq, mockRes);
expect(mockRes.writeHead).toHaveBeenCalledWith(400);
expect(transport.onmessage).not.toHaveBeenCalled();
expect(mockRes.end).toHaveBeenCalledWith(`Invalid message: ${invalidMessage}`);
});
it('should return 202 if message has a valid schema', async () => {
const validMessage = JSON.stringify({
jsonrpc: '2.0',
method: 'call',
params: {
a: 1,
b: 2,
c: 3
},
id: 1
});
const mockReq = createMockRequest({
headers: { host: 'localhost', 'content-type': 'application/json' },
body: validMessage
});
const mockRes = createMockResponse();
const endpoint = '/messages';
const transport = new SSEServerTransport(endpoint, mockRes);
await transport.start();
transport.onmessage = vi.fn();
await transport.handlePostMessage(mockReq, mockRes);
expect(mockRes.writeHead).toHaveBeenCalledWith(202);
expect(mockRes.end).toHaveBeenCalledWith('Accepted');
expect(transport.onmessage).toHaveBeenCalledWith(
{
jsonrpc: '2.0',
method: 'call',
params: {
a: 1,
b: 2,
c: 3
},
id: 1
},
{
authInfo: {
token: 'test-token'
},
requestInfo: {
headers: {
host: 'localhost',
'content-type': 'application/json'
},
url: new URL('http://localhost/messages')
}
}
);
});
});
describe('close method', () => {
it('should call onclose', async () => {
const mockRes = createMockResponse();
const endpoint = '/messages';
const transport = new SSEServerTransport(endpoint, mockRes);
await transport.start();
transport.onclose = vi.fn();
await transport.close();
expect(transport.onclose).toHaveBeenCalled();
});
});
describe('send method', () => {
it('should call onsend', async () => {
const mockRes = createMockResponse();
const endpoint = '/messages';
const transport = new SSEServerTransport(endpoint, mockRes);
await transport.start();
expect(mockRes.write).toHaveBeenCalledTimes(1);
expect(mockRes.write).toHaveBeenCalledWith(expect.stringContaining('event: endpoint'));
expect(mockRes.write).toHaveBeenCalledWith(expect.stringContaining(`data: /messages?sessionId=${transport.sessionId}`));
});
});
describe('DNS rebinding protection', () => {
beforeEach(() => {
vi.clearAllMocks();
});
describe('Host header validation', () => {
it('should accept requests with allowed host headers', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes, {
allowedHosts: ['localhost:3000', 'example.com'],
enableDnsRebindingProtection: true
});
await transport.start();
const mockReq = createMockRequest({
headers: {
host: 'localhost:3000',
'content-type': 'application/json'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(202);
expect(mockHandleRes.end).toHaveBeenCalledWith('Accepted');
});
it('should reject requests with disallowed host headers', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes, {
allowedHosts: ['localhost:3000'],
enableDnsRebindingProtection: true
});
await transport.start();
const mockReq = createMockRequest({
headers: {
host: 'evil.com',
'content-type': 'application/json'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(403);
expect(mockHandleRes.end).toHaveBeenCalledWith('Invalid Host header: evil.com');
});
it('should reject requests without host header when allowedHosts is configured', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes, {
allowedHosts: ['localhost:3000'],
enableDnsRebindingProtection: true
});
await transport.start();
const mockReq = createMockRequest({
headers: {
'content-type': 'application/json'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(403);
expect(mockHandleRes.end).toHaveBeenCalledWith('Invalid Host header: undefined');
});
});
describe('Origin header validation', () => {
it('should accept requests with allowed origin headers', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes, {
allowedOrigins: ['http://localhost:3000', 'https://example.com'],
enableDnsRebindingProtection: true
});
await transport.start();
const mockReq = createMockRequest({
headers: {
origin: 'http://localhost:3000',
'content-type': 'application/json'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(202);
expect(mockHandleRes.end).toHaveBeenCalledWith('Accepted');
});
it('should accept requests without origin headers', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes, {
allowedOrigins: ['http://localhost:3000', 'https://example.com'],
enableDnsRebindingProtection: true
});
await transport.start();
const mockReq = createMockRequest({
headers: {
'content-type': 'application/json'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(202);
expect(mockHandleRes.end).toHaveBeenCalledWith('Accepted');
});
it('should reject requests with disallowed origin headers', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes, {
allowedOrigins: ['http://localhost:3000'],
enableDnsRebindingProtection: true
});
await transport.start();
const mockReq = createMockRequest({
headers: {
origin: 'http://evil.com',
'content-type': 'application/json'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(403);
expect(mockHandleRes.end).toHaveBeenCalledWith('Invalid Origin header: http://evil.com');
});
});
describe('Content-Type validation', () => {
it('should accept requests with application/json content-type', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes);
await transport.start();
const mockReq = createMockRequest({
headers: {
'content-type': 'application/json'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(202);
expect(mockHandleRes.end).toHaveBeenCalledWith('Accepted');
});
it('should accept requests with application/json with charset', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes);
await transport.start();
const mockReq = createMockRequest({
headers: {
'content-type': 'application/json; charset=utf-8'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(202);
expect(mockHandleRes.end).toHaveBeenCalledWith('Accepted');
});
it('should reject requests with non-application/json content-type when protection is enabled', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes);
await transport.start();
const mockReq = createMockRequest({
headers: {
'content-type': 'text/plain'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(400);
expect(mockHandleRes.end).toHaveBeenCalledWith('Error: Unsupported content-type: text/plain');
});
});
describe('enableDnsRebindingProtection option', () => {
it('should skip all validations when enableDnsRebindingProtection is false', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes, {
allowedHosts: ['localhost:3000'],
allowedOrigins: ['http://localhost:3000'],
enableDnsRebindingProtection: false
});
await transport.start();
const mockReq = createMockRequest({
headers: {
host: 'evil.com',
origin: 'http://evil.com',
'content-type': 'text/plain'
}
});
const mockHandleRes = createMockResponse();
await transport.handlePostMessage(mockReq, mockHandleRes, { jsonrpc: '2.0', method: 'test' });
// Should pass even with invalid headers because protection is disabled
expect(mockHandleRes.writeHead).toHaveBeenCalledWith(400);
// The error should be from content-type parsing, not DNS rebinding protection
expect(mockHandleRes.end).toHaveBeenCalledWith('Error: Unsupported content-type: text/plain');
});
});
describe('Combined validations', () => {
it('should validate both host and origin when both are configured', async () => {
const mockRes = createMockResponse();
const transport = new SSEServerTransport('/messages', mockRes, {
allowedHosts: ['localhost:3000'],
allowedOrigins: ['http://localhost:3000'],
enableDnsRebindingProtection: true
});
await transport.start();
// Valid host, invalid origin
const mockReq1 = createMockRequest({
headers: {
host: 'localhost:3000',
origin: 'http://evil.com',
'content-type': 'application/json'
}
});
const mockHandleRes1 = createMockResponse();
await transport.handlePostMessage(mockReq1, mockHandleRes1, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes1.writeHead).toHaveBeenCalledWith(403);
expect(mockHandleRes1.end).toHaveBeenCalledWith('Invalid Origin header: http://evil.com');
// Invalid host, valid origin
const mockReq2 = createMockRequest({
headers: {
host: 'evil.com',
origin: 'http://localhost:3000',
'content-type': 'application/json'
}
});
const mockHandleRes2 = createMockResponse();
await transport.handlePostMessage(mockReq2, mockHandleRes2, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes2.writeHead).toHaveBeenCalledWith(403);
expect(mockHandleRes2.end).toHaveBeenCalledWith('Invalid Host header: evil.com');
// Both valid
const mockReq3 = createMockRequest({
headers: {
host: 'localhost:3000',
origin: 'http://localhost:3000',
'content-type': 'application/json'
}
});
const mockHandleRes3 = createMockResponse();
await transport.handlePostMessage(mockReq3, mockHandleRes3, { jsonrpc: '2.0', method: 'test' });
expect(mockHandleRes3.writeHead).toHaveBeenCalledWith(202);
expect(mockHandleRes3.end).toHaveBeenCalledWith('Accepted');
});
});
});
});
});