add installer alpha version

internal/httpapp/api_handlers.go

@@ -36,6 +36,10 @@ func (a *App) handleListPools(w http.ResponseWriter, r *http.Request) {
 		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
 		return
 	}
+	// Ensure we always return an array, not null
+	if pools == nil {
+		pools = []models.Pool{}
+	}
 	writeJSON(w, http.StatusOK, pools)
 }
 
@@ -215,6 +219,10 @@ func (a *App) handleListDatasets(w http.ResponseWriter, r *http.Request) {
 		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
 		return
 	}
+	// Ensure we always return an array, not null
+	if datasets == nil {
+		datasets = []models.Dataset{}
+	}
 	writeJSON(w, http.StatusOK, datasets)
 }
 
@@ -398,6 +406,10 @@ func (a *App) handleListSnapshots(w http.ResponseWriter, r *http.Request) {
 		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
 		return
 	}
+	// Ensure we always return an array, not null
+	if snapshots == nil {
+		snapshots = []models.Snapshot{}
+	}
 	writeJSON(w, http.StatusOK, snapshots)
 }
 
@@ -485,6 +497,10 @@ func (a *App) handleListSnapshotPolicies(w http.ResponseWriter, r *http.Request)
 	} else {
 		policies = a.snapshotPolicy.List()
 	}
+	// Ensure we always return an array, not null
+	if policies == nil {
+		policies = []models.SnapshotPolicy{}
+	}
 	writeJSON(w, http.StatusOK, policies)
 }
 
@@ -1322,6 +1338,10 @@ func (a *App) handleCreateUser(w http.ResponseWriter, r *http.Request) {
 		req.Role = models.RoleViewer // Default role
 	}
 
+	// Normalize role to lowercase for comparison
+	roleStr := strings.ToLower(string(req.Role))
+	req.Role = models.Role(roleStr)
+
 	// Validate role
 	if req.Role != models.RoleAdministrator && req.Role != models.RoleOperator && req.Role != models.RoleViewer {
 		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "invalid role"})
@@ -1376,6 +1396,12 @@ func (a *App) handleUpdateUser(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Normalize role to lowercase if provided
+	if req.Role != "" {
+		roleStr := strings.ToLower(string(req.Role))
+		req.Role = models.Role(roleStr)
+	}
+
 	// Validate role if provided
 	if req.Role != "" && req.Role != models.RoleAdministrator && req.Role != models.RoleOperator && req.Role != models.RoleViewer {
 		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "invalid role"})