Simple Node script to push real price data into a MongoDB collection.

poll-prices.js

#!/usr/bin/env node
var request = require('request');
var MongoClient = require('mongodb').MongoClient;
var assert = require('assert');

const truefxURL = "http://webrates.truefx.com/rates/connect.html";
const pollFreq = 500;

const mongoURL = (process.argv.length == 3) ? process.argv[2] : 'mongodb://localhost/truefx';
const mongoCollectionName = "currencies";
var mongoCollection;

// Connect to Mongo, get the collection
MongoClient.connect(mongoURL, function(err, db) {
  assert.equal(null, err);
  console.info(`Connected succesfully to ${mongoURL}`);

  mongoCollection = db.collection(mongoCollectionName);
  setInterval(placeTrueFxRequest, pollFreq);
  console.info(`Polling ${truefxURL} every ${pollFreq}ms and populating ${mongoCollectionName}`);
});

function placeTrueFxRequest() {
	request({
		url: truefxURL,
		method: "GET",
		qs: {f: 'csv'}
		}, function(error, response, body){
		    if (!error && response.statusCode == 200) {
		        // Print out the response body
		    	processCurrencyPairs(body);
		    } else {
		    	console.error(`statusCode: ${response.statusCode}`)
		    }
		}
	);
}

function processCurrencyPairs(csvData) {
	const lines = csvData.trim().split("\n");
	var result = {};
	lines.forEach(function(line) {
		var parts = line.split(",");

		var pairName = parts.shift();
		var millis = parts.shift();

		var bidBig = parts.shift();
		var bidPoints = parts.shift();

		var offerBig = parts.shift();
		var offerPoints = parts.shift();

		var high = parts.shift();
		var low = parts.shift();
		var open = parts.shift();

		var document = {
			pairName: pairName,
			timestamp: millis,
			bid: {big: bidBig, points: bidPoints},
			offer: {big: offerBig, points: offerPoints},
			high: high,
			low: low,
			open: open
		}

		mongoCollection.update({pairName: pairName}, document, {upsert: true});
	});
	
}