To Download the latest Linux_64 chrome from https://console.cloud.google.com/storage/browser/chromium-browser-continuous/Linux_x64/?pli=1

chromeDownloader.go

package main

import (
	"context"
	"fmt"
	"io/ioutil"
	"strings"

	"cloud.google.com/go/storage"
	"github.com/golang/glog"
	"google.golang.org/api/option"
)

const (
	chromeBrowserBktName = "chromium-browser-continuous"
	prefixLinux64        = "Linux_x64"
	objLastChange        = "Linux_x64/LAST_CHANGE"
	chromeFilename       = "chrome-linux.zip"
)

// Notes:
// chromium-browser-continuous/Linux_x64/"LAST_CHANGE" file has the latest object name.
// Read that file and then, go to that object and then, to the latest object to download the chrome file.

// https://github.com/GoogleCloudPlatform/golang-samples/tree/master/storage
// https://console.cloud.google.com/storage/browser/chromium-browser-continuous/?pli=1

// Check the checksum after downloading the file.

func main() {
	ctx := context.Background()
	client, err := storage.NewClient(ctx, option.WithServiceAccountFile("/home/ravitezu/creds.json"))
	if err != nil {
		glog.Infof("Cannot create a storage client: %s", err)
	}
	chromeBkt := client.Bucket(chromeBrowserBktName)
	// Get the latest build version using objLAST_CHANGE object
	lastChange := chromeBkt.Object(objLastChange)
	rc, err := lastChange.NewReader(ctx)
	if err != nil {
		glog.Infof("Cannot get a reader for LAST_CHANGE: %s", err)
	}
	defer rc.Close()

	data, err := ioutil.ReadAll(rc)
	if err != nil {
		glog.Infof("Cannot read from LAST_CHANGE: %s", err)
	}
	latestChromeBuild := string(data)
	latestChromePackage := strings.Join([]string{prefixLinux64, latestChromeBuild, chromeFilename}, "/")
	latestObjHandler := chromeBkt.Object(latestChromePackage)
	chromeZip, err := latestObjHandler.NewReader(ctx)
	if err != nil {
		glog.Infof("Cannot get a reader for LAST_CHANGE: %s", err)
	}
	defer chromeZip.Close()

	fileData, err := ioutil.ReadAll(chromeZip)
	if err != nil {
		glog.Infof("Cannot get a reader for LAST_CHANGE: %s", err)
	}
	fmt.Println("Downloading the latest chrome version ... ")
	err = ioutil.WriteFile(chromeFilename, fileData, 0644)
	if err != nil {
		glog.Infof("Cannot write to file: %s", err)
	}
}