From io.Reader to io.Writer

io_reader_to_writer.go

package main

import (
	"fmt"
	"io"
	"io/ioutil"
	"log"
	"net/http"
	"os"
)

func main() {
	response, err := http.Get("http://nanite.tistory.com")
	if err != nil {
		log.Fatal(err)
	}
	defer response.Body.Close()

	// 1_ io.Copy()
	// io.Reader -> io.Writer
	n, err := io.Copy(os.Stdout, response.Body)
	if err != nil {
		log.Fatal(err)
	}
	log.Println("Number of bytes copied to STDOUT:", n)

	// 2_ ioutil.ReadAll()
	// io.Reader -> []byte
	body, err := ioutil.ReadAll(response.Body)
	fmt.Println(string(body))
}