Retrieve images of products according to ean code

gistfile1.go

package main

import (
	"bytes"
	"encoding/json"
	"image"
	"image/color"
	"image/draw"
	"image/jpeg"
	"io/ioutil"
	"log"
	"net/http"
	"os"
	"strconv"
	"text/template"

	"github.com/nfnt/resize"
)

const SIDELENGTH int = 300

func handleImageFromLink(link string, ean string) int {
	if link == "" {
		return 400
	}

	resp, err := http.Get(link)
	if err != nil {
		log.Print(err)
		return 400
	}
	log.Print(link + " HTTP GET status code: " + strconv.Itoa(resp.StatusCode))

	if resp.StatusCode != 200 {
		return 400
	}

	var img image.Image
	img, err = jpeg.Decode(resp.Body)
	if err != nil {
		log.Print(err)
		return 400
	}

	file, err := os.Create("./img/" + ean + ".jpg")
	if err != nil {
		log.Print(err)
		return 400
	}

	bounds := img.Bounds()

	// resize img to the right size
	if bounds.Max.X < bounds.Max.Y {
		img = resize.Resize(0, uint(SIDELENGTH), img, resize.Bicubic)
	} else {
		img = resize.Resize(uint(SIDELENGTH), 0, img, resize.Bicubic)
	}

	// add white so that img becomes square
	bounds = img.Bounds()
	xd := (SIDELENGTH - bounds.Max.X) / 2
	yd := (SIDELENGTH - bounds.Max.Y) / 2

	// create image with sie 187 187
	timg := image.NewRGBA(image.Rect(0, 0, SIDELENGTH, SIDELENGTH))
	draw.Draw(timg, timg.Bounds(), &image.Uniform{color.White}, image.ZP, draw.Src)
	draw.Draw(timg, image.Rect(xd, yd, SIDELENGTH, SIDELENGTH), img, image.ZP, draw.Src)

	jpeg.Encode(file, timg, nil)
	return 200
}

type product struct {
	Ean    string
	Nimike string
}

func main() {
	products, err := ioutil.ReadFile("./products.json")
	if err != nil {
		log.Print(err)
	}
	var prods []product
	err = json.Unmarshal(products, &prods)
	if err != nil {
		log.Print(err)
	}

	marketImageURL, err := template.New("marketImage").Parse("https://www.k-ruokakauppa.fi/Image/products/{{.Ean}}.jpg")
	if err != nil {
		log.Print(err)
	}
	kesproImageURL, err := template.New("kesproImage").Parse("https://www.kespro.com/Image/products/{{.Ean}}.jpg")
	if err != nil {
		log.Print(err)
	}

	image.RegisterFormat("jpeg", "jpeg", jpeg.Decode, jpeg.DecodeConfig)

	var tempURL bytes.Buffer
	for _, prod := range prods {
		marketImageURL.Execute(&tempURL, prod)
		link := tempURL.String()
		code := handleImageFromLink(link, prod.Ean)
		tempURL.Reset()
		if code != 200 {
			kesproImageURL.Execute(&tempURL, prod)
			link := tempURL.String()
			code = handleImageFromLink(link, prod.Ean)
			tempURL.Reset()
		}
	}
}