feat: add books APIs

internal/middleware/auth.go

@@ -0,0 +1,57 @@
+package middleware
+
+import (
+	"context"
+	"net/http"
+	"strings"
+
+	"github.com/prabhupadasays/spsays-bff/pkg/response"
+)
+
+type contextKey string
+
+const UserIDKey contextKey = "user_id"
+
+// Auth is a placeholder middleware for JWT authentication.
+// It extracts the Bearer token from the Authorization header,
+// validates it, and sets the user ID in the request context.
+func Auth(jwtSecret string) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			authHeader := r.Header.Get("Authorization")
+			if authHeader == "" {
+				response.Error(w, http.StatusUnauthorized, "missing authorization header")
+				return
+			}
+
+			parts := strings.SplitN(authHeader, " ", 2)
+			if len(parts) != 2 || strings.ToLower(parts[0]) != "bearer" {
+				response.Error(w, http.StatusUnauthorized, "invalid authorization format")
+				return
+			}
+
+			token := parts[1]
+
+			// TODO: validate JWT token and extract user ID
+			_ = token
+			_ = jwtSecret
+			userID := "" // placeholder
+
+			if userID == "" {
+				response.Error(w, http.StatusUnauthorized, "invalid or expired token")
+				return
+			}
+
+			ctx := context.WithValue(r.Context(), UserIDKey, userID)
+			next.ServeHTTP(w, r.WithContext(ctx))
+		})
+	}
+}
+
+// GetUserID extracts the user ID from the request context.
+func GetUserID(ctx context.Context) string {
+	if v, ok := ctx.Value(UserIDKey).(string); ok {
+		return v
+	}
+	return ""
+}