go-jwtserver/internal/jwtcontroller/jwt.go

82 lines
2.5 KiB
Go

package jwtcontroller
import (
"context"
"fmt"
"log"
"net/http"
"os"
"strings"
jwt "github.com/dgrijalva/jwt-go"
)
// JwtAuthentication is a Jwt Auth controller with postgres database
var JwtAuthentication = func(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
notAuth := []string{"/api/user/new", "/api/user/login"} //List of endpoints that doesn't require auth
requestPath := r.URL.Path //current request path
//check if request does not need authentication, serve the request if it doesn't need it
for _, value := range notAuth {
if value == requestPath {
next.ServeHTTP(w, r)
return
}
}
response := make(map[string]interface{})
tokenHeader := r.Header.Get("Authorization") //Grab the token from the header
if tokenHeader == "" { //Token is missing, returns with error code 403 Unauthorized
response = Message(false, "Missing auth token")
w.WriteHeader(http.StatusForbidden)
w.Header().Add("Content-Type", "application/json")
Respond(w, response)
return
}
splitted := strings.Split(tokenHeader, " ") //The token normally comes in format `Bearer {token-body}`, we check if the retrieved token matched this requirement
if len(splitted) != 2 {
response = Message(false, "Invalid/Malformed auth token")
w.WriteHeader(http.StatusForbidden)
w.Header().Add("Content-Type", "application/json")
Respond(w, response)
return
}
tokenPart := splitted[1] //Grab the token part, what we are truly interested in
tk := &Token{}
log.Println(splitted)
token, err := jwt.ParseWithClaims(tokenPart, tk, func(token *jwt.Token) (interface{}, error) {
return []byte(os.Getenv("token_password")), nil
})
if err != nil { //Malformed token, returns with http code 403 as usual
response = Message(false, "Malformed authentication token")
w.WriteHeader(http.StatusForbidden)
w.Header().Add("Content-Type", "application/json")
Respond(w, response)
return
}
if !token.Valid { //Token is invalid, maybe not signed on this server
response = Message(false, "Token is not valid.")
w.WriteHeader(http.StatusForbidden)
w.Header().Add("Content-Type", "application/json")
Respond(w, response)
return
}
//Everything went well, proceed with the request and set the caller to the user retrieved from the parsed token
fmt.Sprintf("User %", tk) //Useful for monitoring
ctx := context.WithValue(r.Context(), "user", tk.UserId)
r = r.WithContext(ctx)
next.ServeHTTP(w, r) //proceed in the middleware chain!
})
}