Send a request to an IP address but use a specific hostname

sni.go

package main

import (
	"crypto/tls"
	"log"
	"net/http"
)

func main() {
	client := &http.Client{
		Transport: &http.Transport{
			TLSClientConfig: &tls.Config{
				ServerName: "sendgrid.com",
			},
		},
	}

	req, err := http.NewRequest("GET", "https://167.89.118.65", nil)
	if err != nil {
		log.Fatal(err)
	}

	resp, err := client.Do(req)
	if err != nil {
		log.Fatal(err)
	}
	defer resp.Body.Close()

	log.Printf("statusCode=%d", resp.StatusCode)
}