Initial commit

middleware/middleware.go

@@ -0,0 +1,49 @@
+package middleware
+
+import (
+	"fmt"
+	"net/http"
+
+	"git.beisel.it/florian/hostname-service/config"
+	"github.com/dgrijalva/jwt-go"
+	"github.com/gin-gonic/gin"
+)
+
+func Authenticate() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		const Bearer_schema = "Bearer "
+		header := c.GetHeader("Authorization")
+		if header == "" {
+			c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "No token provided"})
+			return
+		}
+
+		tokenString := header[len(Bearer_schema):]
+		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 config.JwtKey, nil
+		})
+
+		if err != nil {
+			c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "Invalid token: " + err.Error()})
+			return
+		}
+
+		if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
+			// Extract the username from the MapClaims
+			if username, ok := claims["sub"].(string); ok {
+				c.Set("username", username)
+			} else {
+				c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "Invalid token claims"})
+				return
+			}
+		} else {
+			c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "Invalid token"})
+			return
+		}
+
+		c.Next()
+	}
+}