AWS Lambda read file using NodeJS

Question

I try to create a lambda function for sending the email. The problem is I cannot get the email template path on Lambda. The error I received is:

"errorMessage": "ENOENT: no such file or directory, open '/var/task/email_template.ejs'"

Here are my project structure and my code:

service.js:

export const generateEmail = async (subject, text, email) => {
  try {
    const pathName = process.env.LAMBDA_TASK_ROOT
      ? path.resolve(process.env.LAMBDA_TASK_ROOT, 'email_template.ejs')
      : path.resolve(__dirname, 'email_template.ejs')

    const data = await ejs.renderFile(pathName, {
      name: 'John Doe'
    })

    return {
      from: '"Service" <[email protected]>',
      to: email,
      subject: subject,
      text: text,
      html: data
    }
  } catch (err) {
    throw err
  }
}

sendMail.js

exports.handler = async (event, context, callback) => {
  if (event.httpMethod === 'POST' && event.body) {
    const req = JSON.parse(event.body)
    const { name, email } = req

    if (!email.match(/^[^@]+@[^@]+$/)) {
      console.log('Not sending: invalid email address', body.email)
      return callback(null, {
        statusCode: 400,
        body: JSON.stringify({
          error_code: 'invalid_email',
          message: 'Cannot send. Your email is invalid'
        })
      })
    }

    const config = {
      accessKeyId: process.env.ACCESS_KEY,
      secretAccessKey: process.env.SECRET_KEY
    }

    const transporter = nodemailer.createTransport(ses(config))
    const mailOptions = await generateEmail('Hello ✔', 'Hello world', email)

    try {
      await transporter.sendMail(mailOptions)
      return callback(null, {
        statusCode: 204
      })
    } catch (err) {
      return callback(null, {
        statusCode: 400,
        body: JSON.stringify({
          error_code: 'general_error',
          message: 'Please try again later',
          full_error: err
        })
      })
    }
  }

  return callback(null, {
    statusCode: 400,
    body: JSON.stringify({
      error_code: 'missing_parameters',
      message: 'Please provide your name and email'
    })
  })
}

The generateEmail function works perfectly on locally but it did not work on lambda function.

Any help would be appreciated, thanks!

Your template is probably in path.resolve(process.env.LAMBDA_TASK_ROOT, 'src/email_template.ejs') — Paul
Thanks Paulpro, I also tried this, but it did not work either — M.Tae
I think it could be the case where my email_template.ejs file was not built by webpack and deployed. — M.Tae

M.Tae M.Tae · Accepted Answer · 2019-07-02T15:57:18

I finally found the answer by myself. The reason because when webpack build, it ignores my email_template.ejs file.

So I add this line to my webpack.config.js to make it exist on my zip output and It works perfectly.

  (...),
  plugins: [
    new CopyWebpackPlugin([{ from: './src/email_template.ejs', to: './src' }])
  ]

AWS Lambda read file using NodeJS

1 Answers