mcp-http-client.js•3.36 kB
#!/usr/bin/env node
/**
* Minimal MCP HTTP Client for Node.js v16 compatibility
* This bypasses mcp-remote and its TransformStream dependency
*/
const http = require('http');
const https = require('https');
const readline = require('readline');
// Get configuration from command line arguments
const url = process.argv[2];
const authToken = process.env.MCP_AUTH_TOKEN;
if (!url) {
console.error('Usage: node mcp-http-client.js <server-url>');
process.exit(1);
}
if (!authToken) {
console.error('Error: MCP_AUTH_TOKEN environment variable is required');
process.exit(1);
}
// Parse URL
const parsedUrl = new URL(url);
const isHttps = parsedUrl.protocol === 'https:';
const httpModule = isHttps ? https : http;
// Create readline interface for stdio
const rl = readline.createInterface({
input: process.stdin,
output: process.stdout,
terminal: false
});
// Buffer for incomplete JSON messages
let buffer = '';
// Function to send JSON-RPC request
function sendRequest(request) {
const requestBody = JSON.stringify(request);
const options = {
hostname: parsedUrl.hostname,
port: parsedUrl.port || (isHttps ? 443 : 80),
path: parsedUrl.pathname,
method: 'POST',
headers: {
'Content-Type': 'application/json',
'Content-Length': Buffer.byteLength(requestBody),
'Authorization': `Bearer ${authToken}`
}
};
const req = httpModule.request(options, (res) => {
let responseData = '';
res.on('data', (chunk) => {
responseData += chunk;
});
res.on('end', () => {
try {
const response = JSON.parse(responseData);
// Ensure the response has the correct structure
if (response.jsonrpc && (response.result !== undefined || response.error !== undefined)) {
console.log(JSON.stringify(response));
} else {
// Wrap non-JSON-RPC responses
console.log(JSON.stringify({
jsonrpc: '2.0',
id: request.id || null,
error: {
code: -32603,
message: 'Internal error',
data: response
}
}));
}
} catch (err) {
console.log(JSON.stringify({
jsonrpc: '2.0',
id: request.id || null,
error: {
code: -32700,
message: 'Parse error',
data: err.message
}
}));
}
});
});
req.on('error', (err) => {
console.log(JSON.stringify({
jsonrpc: '2.0',
id: request.id || null,
error: {
code: -32000,
message: 'Transport error',
data: err.message
}
}));
});
req.write(requestBody);
req.end();
}
// Process incoming JSON-RPC messages from stdin
rl.on('line', (line) => {
// Try to parse each line as a complete JSON-RPC message
try {
const request = JSON.parse(line);
// Forward the request to the HTTP server
sendRequest(request);
} catch (err) {
// Log parse errors to stdout in JSON-RPC format
console.log(JSON.stringify({
jsonrpc: '2.0',
id: null,
error: {
code: -32700,
message: 'Parse error',
data: err.message
}
}));
}
});
// Handle process termination
process.on('SIGINT', () => {
process.exit(0);
});
process.on('SIGTERM', () => {
process.exit(0);
});