Sendgrid helper

import { Meteor } from 'meteor/meteor';
import Sendgrid from 'sendgrid';
import * as helper from 'sendgrid/lib/helpers/mail/mail';
import _ from 'lodash';

// Article
// https://medium.com/@jamielob/sending-branded-emails-from-node-js-66ffa9c5a6c6#.kddhj4go6

export const sendTemplateEmail = ({
  templateId,
  subject,
  to,
  substitutions,
}) => {
  const {
    SENDGRID_KEY,
  } = Meteor.settings;

  const mailer = Sendgrid(SENDGRID_KEY);

  const email = new helper.Mail();

  const fromEmail = new helper.Email('[email protected]');
  email.setFrom(fromEmail);

  email.setSubject(subject);

  const content = new helper.Content('text/html', 'Template');
  email.addContent(content);

  const personalization = new helper.Personalization();

  const toEmail = new helper.Email(to);
  personalization.addTo(toEmail);

  _.each(substitutions, ([variable, value]) => {
    const sub = new helper.Substitution(variable, value);
    personalization.addSubstitution(sub);
  });

  email.addPersonalization(personalization);

  email.setTemplateId(templateId);

  const request = mailer.emptyRequest({
    method: 'POST',
    path: '/v3/mail/send',
    body: email.toJSON(),
  });

  mailer.API(request, (e, response) => {
    if (e) {
      throw new Error(e.message);
    }
    return response;
  });
};

// sendTemplateEmail({
//   templateId: '88f55776-d556-42cd-a668-dd55c925e342',
//   subject: 'Welcome!',
//   to: '[email protected]',
//   substitutions: [
//     ['%firstName%', 'Jamie'],
//   ],
// });