Google Cloud Function for sending an email via SendGrid, triggered by a document being added to Firestore

index.js

const functions = require('firebase-functions')

const admin = require('firebase-admin')
admin.initializeApp(functions.config().firebase)

const SENDGRID_API_KEY = functions.config().sendgrid.key

const sendGridEmail = require('@sendgrid/mail')
sendGridEmail.setApiKey(SENDGRID_API_KEY)

exports.inviteStudentEmail = functions.firestore
  .document('emailtest/{emailtestId}')
  .onCreate((event) => {
    const emailTestData = event.data()
    const msg = {
      to: emailTestData.emailAddress,
      from: 'noreply@juniortechbots.com',
      subject: 'My subject',
      templateId: '<enter your template id here>',
      dynamic_template_data: {
        clubname: emailTestData.clubname
      }
    }

    return sendGridEmail
      .send(msg)
      .then(() => console.log('email sent'))
      .catch((error) => console.error(error.toString()))
  })