handler.js

'use strict';

const { tickerGenerator } = require('./functions/ticker');
const { generate } = require('./functions/cmc-data-generator');
const AWS = require('aws-sdk'); // eslint-disable-line import/no-extraneous-dependencies
const _ = require('lodash');
const Logger = require('./functions/utils/logger');

const s3 = new AWS.S3();
const LOG_FILE = 'v1/log.txt';

module.exports.ticker = (event, context, callback) => {
    tickerGenerator()
        .then(({files, log}) => updateLog(log).then(() => files))
        .then((files) => putFiles(files))
        .then(() => generate())
        .then((files) => putFiles(files))
        .then(v => callback(null, v), callback);
};

function putFiles(files) {
    return Promise.all(_.map(files, (contents, filename) => {
        return s3.putObject({
            Bucket: process.env.BUCKET,
            Key: filename,
            Body: contents,
            ContentType: 'application/json',
            ACL: 'public-read',
            CacheControl: 'public, max-age=50',
        }).promise()
    }));
}

function updateLog(log) {
    return s3.getObject({
        Bucket: process.env.BUCKET,
        Key: LOG_FILE
    }).promise()
      .then((data) => Logger.prepareLog(data.Body.toString('ascii') || ''))
      .catch(() => '')
      .then((currentLog) =>  s3.putObject({
          Bucket: process.env.BUCKET,
          Key: LOG_FILE,
          Body: `${log}\n\n\n${currentLog}`.trim(),
          ContentType: 'text/plain',
          ACL: 'public-read',
          CacheControl: 'public, max-age=50',
      }).promise())
      .catch()
}