Proxy Video Server

ProxyVideoServer.go

package main

import (
	"fmt"
	"io"
	"net/http"
	"os"
	"path"
)

const Folder = "./example"
const ServerVideoAddr = "http://www.sample-videos.com/video/mp4/720"

func main() {
	var s = http.NewServeMux()
	var addr = ":3000"
	// var fs = http.FileServer(http.Dir(Folder))
	// s.Handle("/static/", http.StripPrefix("/static", fs))
	// s.Handle("/", http.FileServer(http.Dir(Folder)))
	s.HandleFunc("/", handleReadVideo)
	fmt.Println("Listen on %v", addr)
	if err := http.ListenAndServe(addr, s); err != nil {
		fmt.Println("Listen on %v error %v", addr, err.Error())
	}
}

func handleReadVideo(w http.ResponseWriter, r *http.Request) {
	// 1. Read file from file system
	var filename = r.URL.Path
	if _, err := os.Stat(path.Join(Folder, filename)); !os.IsNotExist(err) {
		fmt.Println("File ko ton tai")
		err = downloadFile(path.Join(Folder, filename), ServerVideoAddr+r.URL.Path)
		if err != nil {
			fmt.Printf("%v", err)
			http.Error(w, "Can not dowload file in server", http.StatusInternalServerError)
			return
		}
	}
	file, err := os.Open(path.Join(Folder, filename))
	if err != nil {
		fmt.Printf("%v", err)
		http.Error(w, "Can not open file", http.StatusInternalServerError)
		return
	}
	_, err = io.Copy(w, file)
	if err != nil {
		fmt.Printf("%v", err)
		http.Error(w, "File not found", http.StatusInternalServerError)
		return
	}
}

func downloadFile(filepath string, url string) error {
	fmt.Println("File path: ", filepath)
	fmt.Println("Url: ", url)
	out, err := os.Create(filepath)
	if err != nil {
		return err
	}
	defer out.Close()
	resp, err := http.Get(url)
	if err != nil {
		return err
	}

	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("%v", resp.Status)
	}
	_, err = io.Copy(out, resp.Body)
	if err != nil {
		return err
	}
	return nil
}