Netlify lambda functions not firing first time

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1

Hi,

I have a simple email function that fires inside a netlify lambda function. It uses the AWS SES service.

Sitename: bleachlondon-develop.netlify.app,

The user enters their email, it sends the email address to the function endpoint and we validate and send an email with a magic link in it, code below:

const { v4: uuid } = require("uuid")
const AWS = require("aws-sdk")
AWS.config.update({
  accessKeyId: process.env.VUE_APP_AWS_ACCESS_KEY_ID,
  secretAccessKey: process.env.VUE_APP_AWS_SECRET_ACCESS_KEY,
  region: "eu-west-2"
})

const cognito = new AWS.CognitoIdentityServiceProvider()
const ses = new AWS.SES({
  region: "eu-west-2"
})

/**
 * Returns just type and subtype from Content-Type HTTP header value.
 *
 * @param {string|undefined} headerValue
 * @return {string}
 */
function parseContentType(headerValue) {
  return (headerValue || "").split(/;\s+/, 2)[0]
}

// module.exports.handler = async (event, context, callback)

exports.handler = async function(event) {
  if (event["httpMethod"] !== "POST") {
    return {
      statusCode: 200, // <-- Important!
      headers: {
        "Access-Control-Allow-Origin": "*",
        "Content-Type": "application/json"
      },
      body: "This was not a POST request!"
    }
  }
  if (
    parseContentType(event["headers"]["content-type"]) !==
    "application/json;charset=UTF-8"
  ) {
    return {
      statusCode: 200, // <-- Important!
      headers: {
        "Access-Control-Allow-Origin": "*",
        "Content-Type": "application/json"
      },
      body: `Unexpected content type "${event["headers"]["content-type"]}"`
    }
  }

  try {
    const { email } = JSON.parse(event.body)
    const poolId = process.env.VUE_APP_AWS_USER_POOLS_ID

    // Store challenge as a custom attribute in Cognito
    const authChallenge = uuid()
    await cognito
      .adminUpdateUserAttributes({
        UserAttributes: [
          {
            Name: "custom:authChallenge",
            Value: `${authChallenge},${Math.round(new Date().valueOf() / 1000)}`
          }
        ],
        UserPoolId: poolId,
        Username: email
      })
      .promise()

    const errs = []
    if (!email) errs.push("no-email")
    if (errs.length > 0) {
      return {
        statusCode: 400,
        headers: {
          "Access-Control-Allow-Origin": "*",
          "Content-Type": "application/json"
        },
        body: JSON.stringify({
          error: "Sorry, there is an issue with your account",
          errorDetail: errs
        })
      }
    }

    const link = `${process.env.VUE_APP_BASE_URL_SERVERLESS}/login?validation=${authChallenge}&email=${email}`

    sendEmail(email, link)

    return {
      statusCode: 200,
      headers: {
        "Access-Control-Allow-Origin": "*",
        "Content-Type": "application/json"
      },
      body: JSON.stringify({
        message: "email sent",
        data: link
      })
    }
  } catch (e) {
    return {
      statusCode: 400,
      headers: {
        "Access-Control-Allow-Origin": "*",
        "Content-Type": "application/json"
      },
      body: JSON.stringify({
        error: "Sorry, we could not find your account.",
        errorDetail: e.message
      })
    }
  }

  /**
   * Sends email via AWS SES API.
   *
   * @param {string} replyTo
   * @param {string} text
   * @param {!NetlifyCallback} callback
   */
  function sendEmail(email, url) {
    ses.sendEmail(
      {
        Source: "no-reply@***********",
        Destination: {
          ToAddresses: [email]
        },
        Message: {
          Subject: {
            Charset: "UTF-8",
            Data: "Your Sign In link"
          },
          Body: {
            Html: {
              Charset: "UTF-8",
              Data: `<html><body><p>This is your magic link:</p>
                       <h3>See below</h3><br>${url}</body></html>`
            },
            Text: {
              Charset: "UTF-8",
              Data: `Your Sign in link`
            }
          }
        }
      },
      (err, data) => {
        if (err) {
          console.error("Error while sending email via AWS SES:", err)
          return {
            statusCode: 400, // <-- Important!
            headers: {
              "Access-Control-Allow-Origin": "*",
              "Content-Type": "application/json"
            },
            body: err
          }
        }
        emailData = data
      }
    )
  }
}

This is taken from a function inside my front-end code that posts to the endpoint like so:

try {
            const { data } = axios.post(
              `${process.env.VUE_APP_SERVERLESS_FUNCTION_URL}/login`,
              {
                email
              },
              {
                headers: {
                  "Access-Control-Allow-Origin": "*",
                  Accept: "application/json;charset=UTF-8"
                }
              }
            )
            return data
          } catch (e) {
            console.log("Request failed", e)
            console.log(e.response.data)
          }

There are no errors that come through, I get successful return but the error is in the delivery of the email. The functionality works fine locally but not in build but I cannot find why?

Can anyone help?