auth.go

package main

import (
	"net/http"
	"strings"

	"github.com/golang-jwt/jwt"
	"github.com/miermontoto/url/storage"
)

func DatabaseAuth(storage storage.Storage) func(http.HandlerFunc) http.HandlerFunc {
	return func(next http.HandlerFunc) http.HandlerFunc {
		return func(w http.ResponseWriter, r *http.Request) {
			username, password, ok := r.BasicAuth()
			if !ok || !storage.AuthenticateUser(username, password) {
				w.Header().Set("WWW-Authenticate", `Basic realm="Restricted"`)
				http.Error(w, "Unauthorized", http.StatusUnauthorized)
				return
			}
			r.Header.Set("X-User", username)
			next.ServeHTTP(w, r)
		}
	}
}

func JWTAuth(next http.HandlerFunc) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		tokenString := r.Header.Get("Authorization")

		if tokenString == "" || !strings.HasPrefix(tokenString, "Bearer ") {
			http.Error(w, "Missing token", http.StatusUnauthorized)
			return
		}

		tokenString = tokenString[7:]
		claims := &jwt.StandardClaims{}
		token, err := jwt.ParseWithClaims(tokenString, claims, func(token *jwt.Token) (interface{}, error) {
			return jwtKey, nil
		})

		if err != nil || !token.Valid {
			http.Error(w, "Invalid token", http.StatusUnauthorized)
			return
		}

		r.Header.Set("X-User", claims.Subject)
		next.ServeHTTP(w, r)
	}
}