handler.js

'use strict';

const _ = require('underscore');
const fs = require('fs');
const YAML = require('js-yaml');
const AWS = require('aws-sdk');
const mongodb = require('mongodb');
const postmark = require('postmark');
const moment = require('moment');

let mailClient;
let prod = false;
let sentEmails = 0;
const driveStart = 'kpccPlusDriveStart';
const driveEnd = 'kpccPlusDriveEnd';
const secretPath = './secrets';
const kms = new AWS.KMS({ region: 'us-west-2' });
const encryptedSecret = fs.readFileSync(secretPath);
const MongoClient = mongodb.MongoClient;

const kmsParams = {
  CiphertextBlob: encryptedSecret,
};
const emailSubject = 'Welcome to KPCC Plus!';
const startingTime = new Date().getTime();


function driveTimePromise(db) {
  const collection = db.collection('iPhoneSettings');
  return new Promise((resolve) => {
    collection.find({ settingName: { $in: [driveStart, driveEnd] } }).toArray((err, results) => {
      let driveStartTimestamp;
      let driveEndTimestamp;
      _.each(results, (setting) => {
        if (setting.settingName === driveStart) {
          driveStartTimestamp = setting.settingValue;
        } else if (setting.settingName === driveEnd) {
          driveEndTimestamp = setting.settingValue;
        }
      });
      resolve(driveStartTimestamp && driveEndTimestamp
        && moment(driveStartTimestamp).isBefore(startingTime)
        && moment(driveEndTimestamp).isAfter(startingTime));
    });
  });
}

function sendIndividualEmail(userObject, callback) {
  let name = userObject.firstName || userObject.name
  if (!name) {
    name = '';
  }

  const emailBody = `Dear ${name},<br />
<p>Congratulations! You can now stream KPCC on your computer or mobile device 
during our member drives - without any fundraising interruptions.</p>
<p>The fundraising-free stream KPCC Plus is easy to access. Click or paste this link to listen on your 
desktop or mobile web browser:<br />
http://www.scpr.org/listen_live/pledge-free?pledgeToken=${userObject.pledgeToken}<br /></p>
<p>
To access KPCC Plus via the Android app, tap the antenna icon in the orange navigation bar at the top of the screen.
Choose the "KPCC Plus" stream, and type in ${userObject.pledgeToken}
</p>
<p>
To access KPCC Plus on your iPhone or iPad using our iOS app, tap the Settings button (with the gear icon) on 
the top-right corner of the screen. Choose the "KPCC Standard" option under the Live Stream section, and type 
in ${userObject.pledgeToken}
</p>
<p>
Thanks again for your generous support! Your contribution will go right back into the balanced coverage and inspiring stories you love.
</p>
<p>
Sincerely,<br />
Rob Risko
</p>
<p>
P.S. Having trouble accessing KPCC Plus? Call us at 626-583-5121 or visit our FAQ page: http://www.kpcc.org/plus
</p>`

  const email = prod ? userObject.email : 'louise.yang@scpr.org';
  mailClient.sendEmail({
    To: email,
    From: 'Rob Risko <membership@kpcc.org>',
    Subject: emailSubject,
    HtmlBody: emailBody,
  }, (error) => {
    if (error) {
      console.error(error.message);
      callback.error('Failed to send an email');
      return;
    }
    console.log(`Email sent to ${email}`);
    sentEmails += sentEmails + 1;
    callback.success(true);
  });
}

function findMembersToEmail(db) {
  const collection = db.collection('PfsUser');
  collection.find({ emailSent: { $eq: false } }).toArray((err, results) => {
    if (err) {
      console.log(err);
    } else if (results.length) {
      const handleResult = _.after(results.length, () => {
        const elapsedTime = new Date().getTime() - startingTime;
        console.log(`Attempted to send ${results.length} emails in ${elapsedTime}ms`);
        console.log(`Successfully sent ${sentEmails} emails`);
        db.close();
      });

      _.each(results, (result) => {
        const sendIndividualEmailCallback = {
          success: () => {
            if (prod) {
              collection.updateOne(
                { _id: result._id },
                { $set: { emailSent: true } }
              );
            }
            handleResult();
          },
          error: (error) => {
            console.log(error);
            handleResult();
          },
        };
        sendIndividualEmail(result, sendIndividualEmailCallback);
      });
    } else {
      console.log('No users to email');
      db.close();
    }
  });
}

function sendEmails() {
  console.log(`Running sendEmails (in production? ${prod})`);
  new Promise((resolve, reject) => {
    kms.decrypt(kmsParams, (err, data) => {
      if (err) {
        reject(err);
      } else {
        resolve(data);
      }
    });
  }).then((data) => {
    const secrets = YAML.safeLoad(data.Plaintext.toString());
    mailClient = new postmark.Client(secrets.postmarkKey);

    return new Promise((resolve, reject) => {
      MongoClient.connect(secrets.mongoDbUri, (err, db) => {
        if (err) {
          reject(err);
        } else {
          resolve(db);
        }
      });
    });
  })
  .then((db) => {
    driveTimePromise(db).then((driveTime) => {
      if (!driveTime) {
        console.log('Not drive time. Not emailing anyone');
        db.close();
        return;
      }
      findMembersToEmail(db);
    });
  })
  .catch((err) => {
    console.log(err);
  });
}

module.exports.sendEmails_prod = () => {
  prod = true;
  sendEmails();
};

module.exports.sendEmails_dev = () => {
  prod = false;
  sendEmails();
};