Webflow

import net from "net"; /** * Checks if a given port is free (not currently in use). * @param port - The port number to check. * @returns A Promise that resolves to `true` if the port is free, `false` if it's in use. */ export function isPortFree(port: number): Promise<boolean> { return new Promise((resolve) => { const tester = net .createServer() .once("error", (err: NodeJS.ErrnoException) => { if (err.code === "EADDRINUSE") { resolve(false); // Port is in use } else { resolve(false); // Unexpected error } }) .once("listening", () => { tester.close(() => resolve(true)); // Port is free }) .listen(port); }); } /** * Finds the first available port in the given range. * @param startPort - The starting port number to check. * @param endPort - The ending port number to check. * @returns A Promise that resolves to the first free port number. * @throws Error if no free port is found in the range. */ export async function getFreePort( startPort: number, endPort: number ): Promise<number> { if (startPort > endPort) { throw new Error( `Invalid port range: startPort (${startPort}) must be <= endPort (${endPort})` ); } if (startPort < 1 || endPort > 65535) { throw new Error( `Port numbers must be between 1 and 65535` ); } for (let port = startPort; port <= endPort; port++) { if (await isPortFree(port)) { return port; } } throw new Error( `No free port found in range ${startPort}-${endPort}` ); }