simpleOAuthClient.ts•12.4 kB
#!/usr/bin/env node
import { createServer } from 'node:http';
import { createInterface } from 'node:readline';
import { URL } from 'node:url';
import { exec } from 'node:child_process';
import { Client } from '../../client/index.js';
import { StreamableHTTPClientTransport } from '../../client/streamableHttp.js';
import { OAuthClientInformation, OAuthClientInformationFull, OAuthClientMetadata, OAuthTokens } from '../../shared/auth.js';
import {
CallToolRequest,
ListToolsRequest,
CallToolResultSchema,
ListToolsResultSchema
} from '../../types.js';
import { OAuthClientProvider, UnauthorizedError } from '../../client/auth.js';
// Configuration
const DEFAULT_SERVER_URL = 'http://localhost:3000/mcp';
const CALLBACK_PORT = 8090; // Use different port than auth server (3001)
const CALLBACK_URL = `http://localhost:${CALLBACK_PORT}/callback`;
/**
* In-memory OAuth client provider for demonstration purposes
* In production, you should persist tokens securely
*/
class InMemoryOAuthClientProvider implements OAuthClientProvider {
private _clientInformation?: OAuthClientInformationFull;
private _tokens?: OAuthTokens;
private _codeVerifier?: string;
constructor(
private readonly _redirectUrl: string | URL,
private readonly _clientMetadata: OAuthClientMetadata,
onRedirect?: (url: URL) => void
) {
this._onRedirect = onRedirect || ((url) => {
console.log(`Redirect to: ${url.toString()}`);
});
}
private _onRedirect: (url: URL) => void;
get redirectUrl(): string | URL {
return this._redirectUrl;
}
get clientMetadata(): OAuthClientMetadata {
return this._clientMetadata;
}
clientInformation(): OAuthClientInformation | undefined {
return this._clientInformation;
}
saveClientInformation(clientInformation: OAuthClientInformationFull): void {
this._clientInformation = clientInformation;
}
tokens(): OAuthTokens | undefined {
return this._tokens;
}
saveTokens(tokens: OAuthTokens): void {
this._tokens = tokens;
}
redirectToAuthorization(authorizationUrl: URL): void {
this._onRedirect(authorizationUrl);
}
saveCodeVerifier(codeVerifier: string): void {
this._codeVerifier = codeVerifier;
}
codeVerifier(): string {
if (!this._codeVerifier) {
throw new Error('No code verifier saved');
}
return this._codeVerifier;
}
}
/**
* Interactive MCP client with OAuth authentication
* Demonstrates the complete OAuth flow with browser-based authorization
*/
class InteractiveOAuthClient {
private client: Client | null = null;
private readonly rl = createInterface({
input: process.stdin,
output: process.stdout,
});
constructor(private serverUrl: string) { }
/**
* Prompts user for input via readline
*/
private async question(query: string): Promise<string> {
return new Promise((resolve) => {
this.rl.question(query, resolve);
});
}
/**
* Opens the authorization URL in the user's default browser
*/
private async openBrowser(url: string): Promise<void> {
console.log(`🌐 Opening browser for authorization: ${url}`);
const command = `open "${url}"`;
exec(command, (error) => {
if (error) {
console.error(`Failed to open browser: ${error.message}`);
console.log(`Please manually open: ${url}`);
}
});
}
/**
* Example OAuth callback handler - in production, use a more robust approach
* for handling callbacks and storing tokens
*/
/**
* Starts a temporary HTTP server to receive the OAuth callback
*/
private async waitForOAuthCallback(): Promise<string> {
return new Promise<string>((resolve, reject) => {
const server = createServer((req, res) => {
// Ignore favicon requests
if (req.url === '/favicon.ico') {
res.writeHead(404);
res.end();
return;
}
console.log(`📥 Received callback: ${req.url}`);
const parsedUrl = new URL(req.url || '', 'http://localhost');
const code = parsedUrl.searchParams.get('code');
const error = parsedUrl.searchParams.get('error');
if (code) {
console.log(`✅ Authorization code received: ${code?.substring(0, 10)}...`);
res.writeHead(200, { 'Content-Type': 'text/html' });
res.end(`
<html>
<body>
<h1>Authorization Successful!</h1>
<p>You can close this window and return to the terminal.</p>
<script>setTimeout(() => window.close(), 2000);</script>
</body>
</html>
`);
resolve(code);
setTimeout(() => server.close(), 3000);
} else if (error) {
console.log(`❌ Authorization error: ${error}`);
res.writeHead(400, { 'Content-Type': 'text/html' });
res.end(`
<html>
<body>
<h1>Authorization Failed</h1>
<p>Error: ${error}</p>
</body>
</html>
`);
reject(new Error(`OAuth authorization failed: ${error}`));
} else {
console.log(`❌ No authorization code or error in callback`);
res.writeHead(400);
res.end('Bad request');
reject(new Error('No authorization code provided'));
}
});
server.listen(CALLBACK_PORT, () => {
console.log(`OAuth callback server started on http://localhost:${CALLBACK_PORT}`);
});
});
}
private async attemptConnection(oauthProvider: InMemoryOAuthClientProvider): Promise<void> {
console.log('🚢 Creating transport with OAuth provider...');
const baseUrl = new URL(this.serverUrl);
const transport = new StreamableHTTPClientTransport(baseUrl, {
authProvider: oauthProvider
});
console.log('🚢 Transport created');
try {
console.log('🔌 Attempting connection (this will trigger OAuth redirect)...');
await this.client!.connect(transport);
console.log('✅ Connected successfully');
} catch (error) {
if (error instanceof UnauthorizedError) {
console.log('🔐 OAuth required - waiting for authorization...');
const callbackPromise = this.waitForOAuthCallback();
const authCode = await callbackPromise;
await transport.finishAuth(authCode);
console.log('🔐 Authorization code received:', authCode);
console.log('🔌 Reconnecting with authenticated transport...');
await this.attemptConnection(oauthProvider);
} else {
console.error('❌ Connection failed with non-auth error:', error);
throw error;
}
}
}
/**
* Establishes connection to the MCP server with OAuth authentication
*/
async connect(): Promise<void> {
console.log(`🔗 Attempting to connect to ${this.serverUrl}...`);
const clientMetadata: OAuthClientMetadata = {
client_name: 'Simple OAuth MCP Client',
redirect_uris: [CALLBACK_URL],
grant_types: ['authorization_code', 'refresh_token'],
response_types: ['code'],
token_endpoint_auth_method: 'client_secret_post',
scope: 'mcp:tools'
};
console.log('🔐 Creating OAuth provider...');
const oauthProvider = new InMemoryOAuthClientProvider(
CALLBACK_URL,
clientMetadata,
(redirectUrl: URL) => {
console.log(`📌 OAuth redirect handler called - opening browser`);
console.log(`Opening browser to: ${redirectUrl.toString()}`);
this.openBrowser(redirectUrl.toString());
}
);
console.log('🔐 OAuth provider created');
console.log('👤 Creating MCP client...');
this.client = new Client({
name: 'simple-oauth-client',
version: '1.0.0',
}, { capabilities: {} });
console.log('👤 Client created');
console.log('🔐 Starting OAuth flow...');
await this.attemptConnection(oauthProvider);
// Start interactive loop
await this.interactiveLoop();
}
/**
* Main interactive loop for user commands
*/
async interactiveLoop(): Promise<void> {
console.log('\n🎯 Interactive MCP Client with OAuth');
console.log('Commands:');
console.log(' list - List available tools');
console.log(' call <tool_name> [args] - Call a tool');
console.log(' quit - Exit the client');
console.log();
while (true) {
try {
const command = await this.question('mcp> ');
if (!command.trim()) {
continue;
}
if (command === 'quit') {
break;
} else if (command === 'list') {
await this.listTools();
} else if (command.startsWith('call ')) {
await this.handleCallTool(command);
} else {
console.log('❌ Unknown command. Try \'list\', \'call <tool_name>\', or \'quit\'');
}
} catch (error) {
if (error instanceof Error && error.message === 'SIGINT') {
console.log('\n\n👋 Goodbye!');
break;
}
console.error('❌ Error:', error);
}
}
}
private async listTools(): Promise<void> {
if (!this.client) {
console.log('❌ Not connected to server');
return;
}
try {
const request: ListToolsRequest = {
method: 'tools/list',
params: {},
};
const result = await this.client.request(request, ListToolsResultSchema);
if (result.tools && result.tools.length > 0) {
console.log('\n📋 Available tools:');
result.tools.forEach((tool, index) => {
console.log(`${index + 1}. ${tool.name}`);
if (tool.description) {
console.log(` Description: ${tool.description}`);
}
console.log();
});
} else {
console.log('No tools available');
}
} catch (error) {
console.error('❌ Failed to list tools:', error);
}
}
private async handleCallTool(command: string): Promise<void> {
const parts = command.split(/\s+/);
const toolName = parts[1];
if (!toolName) {
console.log('❌ Please specify a tool name');
return;
}
// Parse arguments (simple JSON-like format)
let toolArgs: Record<string, unknown> = {};
if (parts.length > 2) {
const argsString = parts.slice(2).join(' ');
try {
toolArgs = JSON.parse(argsString);
} catch {
console.log('❌ Invalid arguments format (expected JSON)');
return;
}
}
await this.callTool(toolName, toolArgs);
}
private async callTool(toolName: string, toolArgs: Record<string, unknown>): Promise<void> {
if (!this.client) {
console.log('❌ Not connected to server');
return;
}
try {
const request: CallToolRequest = {
method: 'tools/call',
params: {
name: toolName,
arguments: toolArgs,
},
};
const result = await this.client.request(request, CallToolResultSchema);
console.log(`\n🔧 Tool '${toolName}' result:`);
if (result.content) {
result.content.forEach((content) => {
if (content.type === 'text') {
console.log(content.text);
} else {
console.log(content);
}
});
} else {
console.log(result);
}
} catch (error) {
console.error(`❌ Failed to call tool '${toolName}':`, error);
}
}
close(): void {
this.rl.close();
if (this.client) {
// Note: Client doesn't have a close method in the current implementation
// This would typically close the transport connection
}
}
}
/**
* Main entry point
*/
async function main(): Promise<void> {
const serverUrl = process.env.MCP_SERVER_URL || DEFAULT_SERVER_URL;
console.log('🚀 Simple MCP OAuth Client');
console.log(`Connecting to: ${serverUrl}`);
console.log();
const client = new InteractiveOAuthClient(serverUrl);
// Handle graceful shutdown
process.on('SIGINT', () => {
console.log('\n\n👋 Goodbye!');
client.close();
process.exit(0);
});
try {
await client.connect();
} catch (error) {
console.error('Failed to start client:', error);
process.exit(1);
} finally {
client.close();
}
}
// Run if this file is executed directly
main().catch((error) => {
console.error('Unhandled error:', error);
process.exit(1);
});