Method connectToHost

src/utils/ssh-tunnel.ts:171–233

* Connect to a single SSH host.

(
    hostInfo: { host: string; port: number; username: string },
    password: string | undefined,
    privateKey: Buffer | undefined,
    passphrase: string | undefined,
    sock: Duplex | undefined,
    label: string | undefined,
    keepaliveInterval?: number,
    keepaliveCountMax?: number
  )

   * Connect to a single SSH host.
   */
  private connectToHost(
    hostInfo: { host: string; port: number; username: string },
    password: string | undefined,
    privateKey: Buffer | undefined,
    passphrase: string | undefined,
    sock: Duplex | undefined,
    label: string | undefined,
    keepaliveInterval?: number,
    keepaliveCountMax?: number
  ): Promise<Client> {
    return new Promise((resolve, reject) => {
      const client = new Client();

      const sshConfig: ConnectConfig = {
        host: hostInfo.host,
        port: hostInfo.port,
        username: hostInfo.username,
      };

      if (password) {
        sshConfig.password = password;
      }
      if (privateKey) {
        sshConfig.privateKey = privateKey;
        if (passphrase) {
          sshConfig.passphrase = passphrase;
        }
      }
      if (sock) {
        sshConfig.sock = sock;
      }
      if (keepaliveInterval !== undefined) {
        if (Number.isNaN(keepaliveInterval) || keepaliveInterval < 0) {
          const desc = label || `${hostInfo.host}:${hostInfo.port}`;
          console.warn(
            `Invalid SSH keepaliveInterval (${keepaliveInterval}) for ${desc}; ` +
            'keepalive configuration will be ignored.'
          );
        } else if (keepaliveInterval > 0) {
          sshConfig.keepaliveInterval = keepaliveInterval * 1000; // Convert seconds to milliseconds
          sshConfig.keepaliveCountMax = keepaliveCountMax ?? 3;
        }
      }

      const onError = (err: Error) => {
        client.removeListener('ready', onReady);
        client.destroy();
        reject(new Error(`SSH connection error${label ? ` (${label})` : ''}: ${err.message}`));
      };

      const onReady = () => {
        client.removeListener('error', onError);
        const desc = label || `${hostInfo.host}:${hostInfo.port}`;
        console.error(`SSH connection established: ${desc}`);
        resolve(client);
      };

      client.on('error', onError);