feat: auth middleware + /me endpoint

internal/api/routes/auth.go

@@ -33,4 +33,9 @@ func RegisterAuthRoutes(cfg *types.StereoConfig, api *gin.RouterGroup) {
 
 		c.String(http.StatusOK, jwt)
 	})
+
+	api.GET("/auth/me", auth.JwtMiddleware(cfg.JWTSecret), func(c *gin.Context) {
+        claims, _ := c.Get("claims")
+		c.JSON(http.StatusOK, claims)
+	})
 }

internal/auth/jwt.go

@@ -2,7 +2,10 @@ package auth
 
 import (
 	"fmt"
+	"net/http"
+	"strings"
 
+	"github.com/gin-gonic/gin"
 	"github.com/golang-jwt/jwt/v5"
 )
 
@@ -16,6 +19,33 @@ func GenerateJWT(key string, user User, expiryTimestamp uint64) (string, error)
 	return token.SignedString([]byte(key))
 }
 
+func invalidAuth(c *gin.Context) {
+    c.String(http.StatusUnauthorized, "Unauthorized.")
+    c.Abort()
+}
+
+func JwtMiddleware(secret string) gin.HandlerFunc {
+    return func(c *gin.Context) {
+        jwtSplit := strings.Split(c.GetHeader("Authorization"), " ")
+
+        if jwtSplit[0] != "Bearer" {
+            invalidAuth(c)
+            return
+        }
+
+        claims, err := ValidateJWT(jwtSplit[1], secret)
+
+        if err != nil {
+            invalidAuth(c)
+            return
+        }
+
+        c.Set("claims", claims)
+
+        c.Next()
+    }
+}
+
 func ValidateJWT(jwtString, key string) (jwt.MapClaims, error) {
 	token, err := jwt.Parse(jwtString, func(token *jwt.Token) (any, error) {
 		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {

internal/auth/types.go

@@ -11,11 +11,11 @@ type TokenResponse struct {
 }
 
 type User struct {
-	ID          string `json:"id" gorm:"primaryKey"`
-	Username    string `json:"username"`
-	Blacklisted bool
-	Email       string `json:"email"`
-	CreatedAt   time.Time
+	ID          string    `json:"id" gorm:"primaryKey"`
+	Username    string    `json:"username"`
+	Blacklisted bool      `json:"blacklisted"`
+	Email       string    `json:"email"`
+	CreatedAt   time.Time `json:"created_at"`
 }
 
 type AvatarDecorationData struct {