fix(synkronus): return JSON content type for user list

synkronus-cli/pkg/client/user_test.go

@@ -0,0 +1,63 @@
+package client
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/OpenDataEnsemble/ode/synkronus-cli/pkg/client/generated"
+)
+
+func TestListUsersParsesSuccessfulJSONResponse(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet {
+			t.Errorf("expected GET request, got %s", r.Method)
+		}
+		if r.URL.Path != "/api/users" {
+			t.Errorf("expected /api/users path, got %s", r.URL.Path)
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+
+		if _, err := w.Write([]byte(`[
+			{
+				"username": "admin",
+				"role": "admin",
+				"created_at": "2026-10-24T12:00:00Z",
+				"updated_at": "2026-10-24T12:00:00Z"
+			}
+		]`)); err != nil {
+			t.Errorf("failed to write response: %v", err)
+		}
+	}))
+	defer server.Close()
+
+	api, err := generated.NewClientWithResponses(server.URL)
+	if err != nil {
+		t.Fatalf("failed to create generated client: %v", err)
+	}
+
+	c := &Client{
+		BaseURL:    server.URL,
+		APIVersion: "1.0",
+		api:        api,
+	}
+
+	users, err := c.ListUsers()
+	if err != nil {
+		t.Fatalf("ListUsers returned an error: %v", err)
+	}
+
+	if len(users) != 1 {
+		t.Fatalf("expected 1 user, got %d", len(users))
+	}
+
+	if users[0].Username != "admin" {
+		t.Errorf("expected username admin, got %s", users[0].Username)
+	}
+
+	if users[0].Role != generated.UserListItemRole("admin") {
+		t.Errorf("expected role admin, got %s", users[0].Role)
+	}
+}

synkronus/internal/handlers/user.go

@@ -109,9 +109,7 @@ func (h *Handler) ListUsersHandler(w http.ResponseWriter, r *http.Request) {
 		SendErrorResponse(w, http.StatusBadRequest, err, err.Error())
 		return
 	}
-	if err := json.NewEncoder(w).Encode(userList); err != nil {
-		h.log.Error("Failed to encode user list response", "error", err)
-	}
+	SendJSONResponse(w, http.StatusOK, userList)
 }
 
 // ChangePasswordRequest represents the request body for changing password

synkronus/internal/handlers/user_test.go

@@ -159,6 +159,23 @@ func TestResetPasswordHandler(t *testing.T) {
 	}
 }
 
+func TestListUsersHandlerReturnsJSONContentType(t *testing.T) {
+	h, mockUserService := userHandlerTestHelper()
+	mockUserService.AddUser(&models.User{
+		Username: "admin",
+		Role:     models.RoleAdmin,
+	})
+
+	r := httptest.NewRequest(http.MethodGet, "/api/users", nil)
+	w := httptest.NewRecorder()
+
+	h.ListUsersHandler(w, r)
+
+	resp := w.Result()
+	assert.Equal(t, http.StatusOK, resp.StatusCode)
+	assert.Equal(t, "application/json", resp.Header.Get("Content-Type"))
+}
+
 func TestChangePasswordHandler(t *testing.T) {
 	h, mockUserService := userHandlerTestHelper()
 	mockUserService.AddUser(&models.User{Username: "changepw", PasswordHash: "oldpw", Role: models.RoleReadOnly})