code: function readSync() {
      const TLS_CERT = process.env.TLS_CERT;
      const TLS_KEY = process.env.TLS_KEY;
      const TLS_CA = process.env.TLS_CA;
      const tls_cert = readOpt("--tls-cert");
      const tls_key = readOpt("--tls-key");
      const tls_ca = readOpt("--tls-ca");
      const result = {
          secureOptions: constants.SSL_OP_NO_TLSv1
      };    
  
      if (tls_cert) {
          if (tls_key) {
              result.cert = fs.readFileSync(tls_cert);
              result.key = fs.readFileSync(tls_key);
  
              if (tls_ca) {
                  result.ca = fs.readFileSync(tls_ca);
              }
          } else {
              result.pfx = fs.readFileSync(tls_cert);
          }
      } else if (TLS_CERT) {
          if (TLS_KEY) {
              result.cert = fs.readFileSync(TLS_CERT);
              result.key = fs.readFileSync(TLS_KEY);
  
              if (TLS_CA) {
                  result.ca = fs.readFileSync(TLS_CA);
              }
          } else {
              result.pfx = fs.readFileSync(TLS_CERT);
          }
      }
  
      return result;
  }
docs: Read TLS options from filesystem synchronously.  Paths are read from CLI
  options or environment variables.
  @returns {object}