CNBC Quote Server

Posted on Feb 24, 2022

Overview

I wanted a quick and dirty way to fetch price quotes from CNBC’s website, so I threw together a quick Go server that does this for equities and futures.

This was purely for educational purposes only, so keep in mind that it may be against their Terms of Service if you do end up actually using this for anything real.

Implementation

package main

import (
	"encoding/json"
	"fmt"
	"net/http"
	"strconv"

	"github.com/gocolly/colly/v2"
	"github.com/gorilla/mux"
	"strings"
)

type (
	Quote struct {
		Symbol string  `json:"symbol"`
		Price  float64 `json:"price"`
		Change float64 `json:"change"`
	}
)

func main() {
	r := mux.NewRouter()
	r.HandleFunc("/{symbol}", func(rw http.ResponseWriter, r *http.Request) {
		vars := mux.Vars(r)
		symbol := vars["symbol"]
		c := colly.NewCollector()

		c.OnHTML(".QuoteStrip-lastPriceStripContainer", func(e *colly.HTMLElement) {
			priceStr := e.ChildText(".QuoteStrip-lastPrice")
			priceStr = strings.Replace(priceStr, ",", "", -1)
			price, _ := strconv.ParseFloat(priceStr, 64)
			changeStr := e.ChildTexts(".QuoteStrip-changeDown span")[0]
			changeStr = strings.Replace(changeStr, ",", "", -1)
			change, _ := strconv.ParseFloat(changeStr, 64)

			quote := Quote{
				Symbol: symbol,
				Price:  price,
				Change: change,
			}

			response, _ := json.Marshal([]Quote{quote})
			rw.Write(response)
		})

		c.Visit(fmt.Sprintf("https://www.cnbc.com/quotes/%s", symbol))
	})
	http.Handle("/", r)
	http.ListenAndServe(":8080", r)
}

Usage

❯ curl localhost:8080/@SP.1,@VX.1
[{"symbol":"@SP.1","price":4258.25,"change":-25.75},{"symbol":"@VX.1","price":29.15,"change":0.6013}]