craban/server/api/auth.go

94 lines
2.3 KiB
Go

package api
import (
"context"
"errors"
"fmt"
"net/http"
"strconv"
"strings"
"git.ctrlz.es/mgdelacroix/craban/model"
"github.com/dgrijalva/jwt-go"
"github.com/rs/zerolog/log"
)
const userContextKey = "user"
func (a *API) Login(w http.ResponseWriter, r *http.Request) {
body := ParseBody(r)
username := body.String("username")
password := body.String("password")
token, err := a.App.Login(username, password)
if err != nil {
http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
return
}
if token == "" {
http.Error(w, http.StatusText(http.StatusForbidden), http.StatusForbidden)
return
}
w.Write([]byte(token))
}
func (a *API) getUserFromToken(tokenStr string) (*model.User, error) {
token, err := jwt.Parse(tokenStr, func(token *jwt.Token) (interface{}, error) {
// Validate the alg is what you expect:
if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, fmt.Errorf("Unexpected signing method: %v", token.Header["alg"])
}
return []byte(*a.App.Config.Secret), nil
})
if err != nil {
return nil, err
}
if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
userIDClaim, ok := claims["userID"].(string)
if !ok {
return nil, errors.New("userID claim is not set")
}
userID, err := strconv.Atoi(userIDClaim)
if err != nil {
return nil, err
}
return a.App.GetUserByID(userID)
} else {
return nil, errors.New("Malformed claims")
}
}
func (a *API) Secured(fn func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) {
return func(w http.ResponseWriter, r *http.Request) {
tokenStr := r.Header.Get("Authorization")
if tokenStr == "" {
http.Error(w, http.StatusText(http.StatusForbidden), http.StatusForbidden)
return
}
if strings.HasPrefix(tokenStr, "Bearer ") {
tokenStr = tokenStr[7:]
}
user, err := a.getUserFromToken(tokenStr)
if err != nil {
log.Debug().Err(err).Str("token", tokenStr).Msg("cannot get user from token")
http.Error(w, http.StatusText(http.StatusForbidden), http.StatusForbidden)
return
}
// get user
ctx := context.WithValue(r.Context(), userContextKey, user)
fn(w, r.Clone(ctx))
}
}
func UserFromRequest(r *http.Request) (*model.User, bool) {
user, ok := r.Context().Value(userContextKey).(*model.User)
return user, ok
}