HowTo: Integrate Google reCAPTCHA with AWS Cognito

handler.js

const axios = require('axios');

// Please replace the property values
const config = {
  recaptcha: {
    secretKey: '<Your reCAPTCHA secret key>',
  },
};

exports.handler = async (event) => {
  if (!event.request.validationData) {
    throw new Error('Missing validation data');
  }

  try {
    const payload = {
      secret: config.recaptcha.secretKey,
      response: event.request.validationData.recaptchaToken,
      remoteip: undefined, // Optional. The user's IP address.
    };

    const verifyResponse = await axios({
      method: 'post',
      url: 'https://www.google.com/recaptcha/api/siteverify',
      params: payload,
    });

    console.log(JSON.stringify(verifyResponse.data));

    if (verifyResponse.data.success) {
      event.response.autoConfirmUser = true;
      return event;
    } else {
      throw new Error('Recaptcha verification failed');
    }
  } catch (error) {
    console.error(error);
    throw error;
  }
};