Braintree Node Server Lambda

BraintreeLambda.js

/***********************************************************************************
AWS Lambda boilerplate for API functions
This boilerplate is designed to be used with AWS API gateway and to return information
to a client
***********************************************************************************/

const util = require("util");

// - provide access to aws-sdk
//const AWS = require('aws-sdk');

// - provide access to mysql databases
// const mysql = require('mysql');

// - unmarshal a DynamodDB item to standard JSON
// const parse = AWS.DynamoDB.Converter.output;

// - used to create unique IDs. requires installation of uuid npm package
// const uuidv1 = require('uuid/v1');

// - set up a docClient to use with dynamoDB store
/* let docClient = new AWS
    .DynamoDB
    .DocumentClient(); */

// - access an environmental variable
// let host = process.env.dbHost;

// create a Braintree gateway
var braintree = require("braintree");
var gateway = braintree.connect({
  environment: braintree.Environment.Sandbox, // either Sandbox or Production
  merchantId: process.env.merchantID, // these come from the Lambda's environmental variables
  publicKey: process.env.publicKey,
  privateKey: process.env.privateKey
});

exports.handler = (event, context, callback) => {
  const done = (err, response) => {
    // return the required callback function
    callback(null, {
      headers: {
        "Access-Control-Allow-Origin": "*", // need if calling API from WebView which is just a browser
        "Content-Type": "application/json",
        "Access-Control-Allow-Headers":
          "Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token"
      },
      statusCode: err ? "400" : "200",
      body: err
        ? JSON.stringify({
            type: "error",
            err
          })
        : JSON.stringify({
            type: "success",
            response
          })
    });
  };

  /*************************************************
   * Braintree related functions based on documentation at
   * https://developers.braintreepayments.com/start/hello-server/node
   */
  /////////////////////////////////////
  // get a client token from Braintree and send it to the client
  /////////////////////////////////////
  const getClientToken = (options = {}) => {
    console.log("getting client token"); // console.logs will show up in AWS Cloudwatch

    let customerId = options && options.hasOwnProperty("customerID")
      ? options.customerID
      : null;

    let merchantAccountId = options && options.hasOwnProperty("merchantAccountID")
      ? options.merchantAccountID
      : null;


    gateway.clientToken
      .generate({
        customerId: customerId,
        merchantAccountId: merchantAccountId
      })
      .then(result => {
        if (!result.success) {
          done(result.message); // call the done function to return an error message to the client
        } else {
          // view the successful response
          console.log(
            "result: ",
            util.inspect(result, {
              showHidden: false,
              depth: null
            })
          );

          // pass the successful response to the client
          done(null, { result });
        }
      })
      .catch(function(err) {
        console.log("+++++++++++++++");
        console.error(err);
        done(err);
      });
  };

  /////////////////////////////////////
  // purchase an item using Braintree's transaction method
  /////////////////////////////////////
  const purchaseItem = purchaseInformation => {
    /* console.log(
      "purchaseInformation: ",
      util.inspect(purchaseInformation, { showHidden: false, depth: null })
    ); */
    gateway.transaction.sale(
      {
        amount: purchaseInformation.amount,
        paymentMethodNonce: purchaseInformation.nonce,
        options: {
          submitForSettlement: true
        }
      },
      function(err, response) {
        console.log(response);
        if (err) {
          console.log("*********");
          console.log({ err });
          done(err);
        } else {
          if (response.success === false) {
            console.log("#################");
            console.log(response.result);
            done({ msg: "Error validating payment server information" });
          } else {
            console.log("~~~~~~~~~~~");
            console.log(response.ErrorResponse);
            done(null, response);
          }
        }
      }
    );
  };

  /*************************************************
   * Enter here
   */
  // view the event that was received
  console.log(
    "event: ",
    util.inspect(event, {
      showHidden: false,
      depth: null
    })
  );

  // try to execute API calls
  try {
    switch (event.queryStringParameters.action) {
      case "get-client-token":
        // call getClientToken with the parsed version of optional body if present, otherwise call it with nothing
        getClientToken(
          event.hasOwnProperty("body") ? JSON.parse(event.body) : null
        );
        break;
      case "purchase-item":
        console.log("purchasing item");
        purchaseItem(JSON.parse(event.body));
        break;
      default:
        done("invalid query string");
        break;
    }
  } catch (error) {
    done(error);
  }
};