Use http proxy in golang gcs package

gcp_poxy.go

package main

import (
	"context"
	"crypto/tls"
	"io"
	"net/http"
	"net/url"

	"cloud.google.com/go/storage"
	"golang.org/x/oauth2"
	"golang.org/x/oauth2/google"
	"google.golang.org/api/option"
)

func main() {
	u, _ := url.Parse("http://127.0.0.1:8888")
	ctx := context.Background()
	cred, err := google.FindDefaultCredentials(ctx)
	if err != nil {
		panic(err)
	}
	client := http.Client{
		Transport: &oauth2.Transport{
			Base: &http.Transport{
				Proxy:           http.ProxyURL(u),
				TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
			},
			Source: cred.TokenSource,
		},
	}
	c, err := storage.NewClient(ctx, option.WithHTTPClient(&client))
	r, err := c.Bucket("bucket").Object("object").NewReader(ctx)
	if err != nil {
		panic(err)
	}
	defer r.Close()
	b, err := io.ReadAll(r)
	if err != nil {
		panic(err)
	}
	println("read", len(b), "bytes")
}