Serverless lambda function which uses middleware to handle warmup, validation, JSON Parsing and error handling.

fetch.js

'use strict';

import ExampleObject from './../objects/ExampleObject';

const schema = {
  "properties": {
    "primaryID": {
      "type": "string",
      "format": "uuid"
    }
  },
  "required": ["primaryID"]
};

const middy = require('middy');

const {
  jsonBodyParser,
  validator,
  warmup,
  httpErrorHandler
} = require('middy/middlewares');

// Our Business Logic
const fetchEndpoint = async(event, context, callback) => {
  let exampleObject = new ExampleObject(event);
  return exampleObject.fetch();
};

const fetchHandler = middy(fetchEndpoint)
  .use(warmup())
  .use(jsonBodyParser())
  .use(validator({
    inputSchema: schema
  }))
  .use(httpErrorHandler());

module.exports.fetch = fetchHandler;