code: function readCertificateDataFromFile ({ keyFile, certFile, caFile }) {
    let key, cert, ca;
  
    if (keyFile) {
      key = fs.readFileSync(keyFile);
    }
  
    if (certFile) {
      cert = fs.readFileSync(certFile);
    }
  
    if (caFile) {
      ca = fs.readFileSync(caFile);
    }
  
    return { key, cert, ca };
  }
docs: Parse endpoint URL if single URL is provided. Extend proxy options by allowing and parsing keyFile, certFile and caFile.