How to Make a Web Scraper with AWS Lambda and the Serverless Framework?

    
     const request = require('axios');
 const AWS = require('aws-sdk');
 const dynamo = new AWS.DynamoDB.DocumentClient();
 const { differenceWith, isEqual } = require('lodash');
 const { extractListingsFromHTML } = require('./helpers');
 

 module.exports.getdonkeyjobs = (event, context, callback) => {
   let newJobs, allJobs;
 

   request('https://www.thedonkeysanctuary.org.uk/vacancies')
     .then(({ data }) => {
       allJobs = extractListingsFromHTML(data);
 

       // Retrieve yesterday's jobs
       return dynamo.scan({
         TableName: 'donkeyjobs'
       }).promise();
     })
     .then(response => {
       // Figure out which jobs are new
       let yesterdaysJobs = response.Items[0] ? response.Items[0].jobs : [];
 

       newJobs = differenceWith(allJobs, yesterdaysJobs, isEqual);
 

       // Get the ID of yesterday's jobs which can now be deleted
       const jobsToDelete = response.Items[0] ? response.Items[0].listingId : null;
 

       // Delete old jobs
       if (jobsToDelete) {
         return dynamo.delete({
           TableName: 'donkeyjobs',
           Key: {
             listingId: jobsToDelete
           }
         }).promise();
       } else return;
     })
     .then(() => {
       // Save the list of today's jobs
       return dynamo.put({
         TableName: 'donkeyjobs',
         Item: {
           listingId: new Date().toString(),
           jobs: allJobs
         }
       }).promise();
     })
     .then(() => {
       callback(null, { jobs: newJobs });
     })
     .catch(callback);
 };