Golang async stock quote fetcher

go_async_stock_prices.go

package main

import (
	"encoding/json"
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
	"sync"
	"time"
)

var prf = fmt.Printf
var srf = fmt.Sprintf

var client = http.Client{
	Timeout: time.Second * 2,
}

var syms = []string{
	"AAPL",
	"AMZN",
	"FB",
	"GOOG",
	"LMT",
	"LULU",
	"NKE",
	"SBUX",
	"SNAP",
	"XOM",
	"YHOO",
}

type Symbol struct {
	Change           int     `json:"-"`
	ChangePercent    float64 `json:"ChangePercent"`
	ChangePercentYTD float64 `json:"ChangePercentYTD"`
	ChangeYTD        float64 `json:"ChangeYTD"`
	High             float64 `json:"High"`
	LastPrice        float64 `json:"LastPrice"`
	Low              float64 `json:"Low"`
	MSDate           int     `json:"-"`
	MarketCap        int     `json:"MarketCap"`
	Name             string  `json:"Name"`
	Open             float64 `json:"Open"`
	Status           string  `json:"Status"`
	Symbol           string  `json:"Symbol"`
	Timestamp        string  `json:"Timestamp"`
	Volume           int     `json:"Volume"`
}

func process(i int, s string, wg *sync.WaitGroup) {
	url := srf("http://dev.markitondemand.com/MODApis/Api/v2/Quote/json?symbol=%s", s)

	req, err := http.NewRequest(http.MethodGet, url, nil)
	if err != nil {
		log.Fatal(err)
	}

	req.Header.Set("User-Agent", "golang-local")

	res, getErr := client.Do(req)
	if getErr != nil {
		log.Fatal(getErr)
	}

	body, readErr := ioutil.ReadAll(res.Body)
	if readErr != nil {
		log.Fatal(readErr)
	}

	var symbol Symbol

	jsonErr := json.Unmarshal(body, &symbol)
	if jsonErr != nil {
		log.Fatal(jsonErr)
	}

	prf("worker.%-6d %-6s - open[%-10.6f], close[%-8.6f]\n", i, s, symbol.Open, symbol.LastPrice)

	wg.Done()
}

func main() {
	var wg sync.WaitGroup

	for i := 0; i < len(syms); i++ {
		wg.Add(1)

		go process(i, syms[i], &wg)
	}

	wg.Wait()
	fmt.Println("All go routines finished executing, stopping process.")
}