JWT Implementation

go.work

 go 1.24.2
 
 use ./src/myaktion
+use ./src/genjwt

src/genjwt/go.mod

+module gitlab.reutlingen-university.de/petrinov/myaktion-go/src/genjwt
+
+go 1.24.2
+
+require github.com/golang-jwt/jwt v3.2.2+incompatible

src/genjwt/go.sum

+github.com/golang-jwt/jwt v3.2.2+incompatible h1:IfV12K8xAKAnZqdXVzCZ+TOjboZ2keLg81eXfW3O+oY=
+github.com/golang-jwt/jwt v3.2.2+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=

src/genjwt/main.go

+package main
+
+import (
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/golang-jwt/jwt"
+)
+
+var secretKey = []byte("myaktion-go-secret-key")
+
+func createToken(username string) (string, error) {
+	claims := jwt.NewWithClaims(jwt.SigningMethodHS256, jwt.MapClaims{
+		"sub": username,
+		"iss": "myaktion-go",
+		"aud": "organizer",
+		"exp": time.Now().Add(time.Hour).Unix(),
+		"iat": time.Now().Unix(),
+	})
+	fmt.Printf("Token claims added: %+v\n", claims)
+	tokenString, err := claims.SignedString(secretKey)
+	if err != nil {
+		return "", err
+	}
+	return tokenString, nil
+}
+
+func main() {
+	if len(os.Args) >= 2 {
+		organizerName := os.Args[1]
+		tokenString, err := createToken(organizerName)
+		if err != nil {
+			fmt.Printf("Unable to create token: %+v\n", err)
+		} else {
+			fmt.Printf("%+v\n", tokenString)
+		}
+	} else {
+		fmt.Println("Please pass a username as command-line argument")
+	}
+}

src/myaktion/go.mod

@@ -12,6 +12,7 @@ require (
 require (
 	filippo.io/edwards25519 v1.1.0 // indirect
 	github.com/go-sql-driver/mysql v1.9.2 // indirect
+	github.com/golang-jwt/jwt v3.2.2+incompatible // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
 	golang.org/x/sys v0.5.0 // indirect

src/myaktion/go.sum

@@ -6,6 +6,8 @@ github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/go-sql-driver/mysql v1.7.0/go.mod h1:OXbVy3sEdcQ2Doequ6Z5BW6fXNQTmx+9S1MCJN5yJMI=
 github.com/go-sql-driver/mysql v1.9.2 h1:4cNKDYQ1I84SXslGddlsrMhc8k4LeDVj6Ad6WRjiHuU=
 github.com/go-sql-driver/mysql v1.9.2/go.mod h1:qn46aNg1333BRMNU69Lq93t8du/dwxI64Gl8i5p1WMU=
+github.com/golang-jwt/jwt v3.2.2+incompatible h1:IfV12K8xAKAnZqdXVzCZ+TOjboZ2keLg81eXfW3O+oY=
+github.com/golang-jwt/jwt v3.2.2+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=
 github.com/gorilla/mux v1.8.1 h1:TuBL49tXwgrFYWhqrNgrUNEY92u81SPhu7sTdzQEiWY=
 github.com/gorilla/mux v1.8.1/go.mod h1:AKf9I4AEqPTmMytcMc0KkNouC66V3BtZ4qD5fmWSiMQ=
 github.com/jinzhu/inflection v1.0.0 h1:K317FqzuhWc8YvSVlFMCCUb36O/S9MCKRDI7QkRKD/E=

src/myaktion/handler/campaign.go

@@ -64,8 +64,8 @@ func GetCampaign(w http.ResponseWriter, r *http.Request) {
 	sendJson(w, campaign)
 }
 
-func GetCampaigns(w http.ResponseWriter, _ *http.Request) {
-	campaigns, err := service.GetCampaigns()
+func GetCampaigns(w http.ResponseWriter, r *http.Request) {
+	campaigns, err := service.GetCampaigns(getOrganizerName(r))
 	if err != nil {
 		log.Printf("Error calling service GetCampaigns: %v", err)
 		http.Error(w, err.Error(), http.StatusInternalServerError)
@@ -118,6 +118,7 @@ func getCampaign(r *http.Request) (*model.Campaign, error) {
 		log.Errorf("Can't serialize request body to campaign struct: %v", err)
 		return nil, err
 	}
+	campaign.OrganizerName = getOrganizerName(r)
 	return &campaign, nil
 }
 
@@ -159,3 +160,7 @@ func PatchCampaign(w http.ResponseWriter, r *http.Request) {
 	}*/
 
 }
+
+func getOrganizerName(r *http.Request) string {
+	return r.Context().Value("organizerName").(string)
+}

src/myaktion/main.go

 package main
 
 import (
+	"context"
+	"fmt"
 	"net/http"
 	"os"
+	"strings"
 
+	"github.com/golang-jwt/jwt"
 	"github.com/gorilla/mux"
 	log "github.com/sirupsen/logrus"
 	"gitlab.reutlingen-university.de/petrinov/myaktion-go/handler"
 )
 
+var secretKey = []byte("myaktion-go-secret-key")
+
+func authMW(next http.HandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		tokenString := r.Header.Get("Authorization")
+		if tokenString == "" {
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+		log.Info(tokenString)
+		tokenString = strings.Replace(tokenString, "Bearer ", "", 1)
+
+		token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
+			if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+				return nil, fmt.Errorf("unexpected signing method")
+			}
+			return []byte(secretKey), nil
+		})
+		if err != nil {
+			log.Errorf("Can' parse token string: %+v\n", err)
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+		if !token.Valid {
+			log.Errorf("Token is not valid: %+v\n", err)
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+		claims, ok := token.Claims.(jwt.MapClaims)
+		if !ok {
+			log.Errorf("Can' extract claims from token: %+v\n", err)
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+		organizerName, ok := claims["sub"].(string)
+		if !ok {
+			log.Errorf("Can' read organizerName from token: %+v\n", err)
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+		if organizerName == "" {
+			log.Errorf("OrganizerName is an empty string: %+v\n", err)
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+		ctx := context.WithValue(r.Context(), "organizerName", organizerName)
+		next(w, r.WithContext(ctx))
+	}
+}
+
 func init() {
 	log.SetFormatter(&log.TextFormatter{})
 	log.SetReportCaller(true)
@@ -25,9 +79,9 @@ func main() {
 	router := mux.NewRouter()
 	router.HandleFunc("/health", handler.Health).Methods("GET")
 
-	router.HandleFunc("/campaigns", handler.CreateCampaign).Methods("POST")
+	router.HandleFunc("/campaigns", authMW(handler.CreateCampaign)).Methods("POST")
 	router.HandleFunc("/campaigns/{id}", handler.UpdateCampaign).Methods("PUT")
-	router.HandleFunc("/campaigns/{id}", handler.GetCampaign).Methods("GET")
+	router.HandleFunc("/campaigns/{id}", authMW(handler.GetCampaign)).Methods("GET")
 	router.HandleFunc("/campaigns", handler.GetCampaigns).Methods("GET")
 	router.HandleFunc("/campaigns/{id}", handler.DeleteCampaign).Methods("DELETE")
 	router.HandleFunc("/campaigns/{id}", handler.PatchCampaign).Methods("PATCH")

src/myaktion/service/campaign.go

@@ -19,9 +19,9 @@ func CreateCampaign(campaign *model.Campaign) error {
 
 }
 
-func GetCampaigns() ([]model.Campaign, error) {
+func GetCampaigns(organizerName string) ([]model.Campaign, error) {
 	var campaigns []model.Campaign
-	result := db.DB.Preload("Donations").Find(&campaigns)
+	result := db.DB.Preload("Donations").Where("organizer_name = ?", organizerName).Find(&campaigns)
 
 	if result.Error != nil {
 		return nil, result.Error