handle.go

package main

import (
	"crypto/hmac"
	"crypto/sha1"
	"fmt"
	"github.com/gorilla/mux"
	"io"
	"log"
	"net/http"
	"net/url"
)

func digestHandler(w http.ResponseWriter, req *http.Request) {

	path := mux.Vars(req)
	query, err := url.ParseQuery(req.URL.RawQuery)

	if err != nil {
		log.Fatal(err.Error())
	}

	if path["digest"] != "" && query["url"][0] != "" {

		destUrl, err := url.QueryUnescape(query["url"][0])
		if err != nil {
			log.Fatal(err.Error())
		}

		hmc := hmac.New(sha1.New, []byte(env.SharedKey))
		io.WriteString(hmc, destUrl)
		sum := fmt.Sprintf("%x", hmc.Sum(nil))

		if path["digest"] == sum {
			destUrl, err := url.Parse(destUrl)

			if err != nil {
				log.Fatal(err.Error())
			}

			proxyImageRequest(&w, destUrl, env.MaxRedirect)
		} else {
			w.WriteHeader(404)
			io.WriteString(w, "not found")
		}

	} else {
		w.WriteHeader(404)
		io.WriteString(w, "not found")
	}
}

func indexHandler(w http.ResponseWriter, _ *http.Request) {
	io.WriteString(w, "pong")
}

func statusHandler(w http.ResponseWriter, _ *http.Request) {
	io.WriteString(w, "status called")
}