handler.js

const aws = require("aws-sdk");
const ses = new aws.SES();
const mainEmail = process.env.MAIN_EMAIL;
const secondaryEmail = process.env.SECONDARY_EMAIL;
const myDomain = process.env.DOMAIN;

function generateResponse(code, payload) {
  return {
    statusCode: code,
    headers: {
      "Access-Control-Allow-Origin": myDomain,
      "Access-Control-Allow-Headers": "x-requested-with",
      "Access-Control-Allow-Credentials": true
    },
    body: JSON.stringify(payload)
  };
}

function generateError(code, err) {
  console.log(err);
  return {
    statusCode: code,
    headers: {
      "Access-Control-Allow-Origin": myDomain,
      "Access-Control-Allow-Headers": "x-requested-with",
      "Access-Control-Allow-Credentials": true
    },
    body: JSON.stringify(err.message)
  };
}

function generateEmailParams(body) {
  const { email, name, subject, message } = JSON.parse(body);
  console.log(email, name, subject, message);
  if (!(email && name && subject && message)) {
    throw new Error("Missing parameters! Make sure to add parameters \'email\', \'name\', \'subject\', \'message\'.");
  }

  return {
    Source: secondaryEmail,
    Destination: { ToAddresses: [mainEmail] },
    ReplyToAddresses: [email],
    Message: {
      Body: {
        Text: {
          Charset: "UTF-8",
          Data: `Message sent from email ${email} by ${name}\nSubject: ${subject}\nMessage: ${message}`
        }
      },
      Subject: {
        Charset: "UTF-8",
        Data: `You received a message from ${myDomain}!`
      }
    }
  };
}

module.exports.send = async (event) => {
  try {
    const emailParams = generateEmailParams(event.body);
    const data = await ses.sendEmail(emailParams).promise();
    return generateResponse(200, data);
  } catch (err) {
    return generateError(500, err);
  }
};