java - 如何在Spring中正确模拟Principal对象？

Question

首先，我在名为 RecipeController 的类中存在以下端点方法:

@RequestMapping(value = {"/", "/recipes"})
    public String listRecipes(Model model, Principal principal){
        List<Recipe> recipes;
        User user = (User)((UsernamePasswordAuthenticationToken)principal).getPrincipal();
        User actualUser = userService.findByUsername(user.getUsername());
        if(!model.containsAttribute("recipes")){
            recipes = recipeService.findAll();
            model.addAttribute("nullAndNonNullUserFavoriteRecipeList",
                    UtilityMethods.nullAndNonNullUserFavoriteRecipeList(recipes, actualUser.getFavoritedRecipes()));

            model.addAttribute("recipes", recipes);
        }

        if(!model.containsAttribute("recipe")){
            model.addAttribute("recipe", new Recipe());
        }

        model.addAttribute("categories", Category.values());
        model.addAttribute("username", user.getUsername());
        return "recipe/index";
    }

正如您在上面所看到的，该方法将 Principal 对象作为第二个参数。运行应用程序时，参数按预期指向非空对象。它包含有关当前在应用程序中登录的用户的信息。

我为RecipeController创建了一个名为RecipeControllerTest的测试类。此类包含一个名为 testListRecipes 的方法。

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration
@WebAppConfiguration
public class RecipeControllerTest{

    @Mock
    private RecipeService recipeService;

    @Mock
    private IngredientService ingredientService;

    @Mock
    private StepService stepService;

    @Mock
    private UserService userService;

    @Mock
    private UsernamePasswordAuthenticationToken principal;

    private RecipeController recipeController;

    private MockMvc mockMvc;

    @Before
    public void setUp(){
        MockitoAnnotations.initMocks(this);

        recipeController = new RecipeController(recipeService,
                ingredientService, stepService, userService);

        mockMvc = MockMvcBuilders.standaloneSetup(recipeController).build();
    }

    @Test
    public void testListRecipes() throws Exception {
        User user = new User();

        List<Recipe> recipes = new ArrayList<>();
        Recipe recipe = new Recipe();
        recipes.add(recipe);

        when(principal.getPrincipal()).thenReturn(user);
        when(userService.findByUsername(anyString()))
                .thenReturn(user);
        when(recipeService.findAll()).thenReturn(recipes);

        mockMvc.perform(get("/recipes"))
                .andExpect(status().isOk())
                .andExpect(view().name("recipe/index"))
                .andExpect(model().attributeExists("recipes"))
                .andExpect(model().attributeExists("recipe"))
                .andExpect(model().attributeExists("categories"))
                .andExpect(model().attributeExists("username"));

        verify(userService, times(1)).findByUsername(anyString());
        verify(recipeService, times(1)).findAll();
    }
}

正如您在第二个代码片段中看到的，我尝试使用 UsernamePasswordAuthenticationToken 实现来模拟测试类中的 Principal 对象。

当我运行测试时，我得到一个NullPointerException，并且堆栈跟踪将我指向第一个代码片段中的以下行:

User user = (User)((UsernamePasswordAuthenticationToken)principal).getPrincipal();

作为参数传递给 listRecipes 方法的主体对象仍然为 null，即使我尝试提供一个模拟对象。

有什么建议吗？

Answer 1

创建一个实现 Principal 的类:

class PrincipalImpl implements Principal {

    @Override
    public String getName() {

        return "XXXXXXX";
    }

}

示例测试:

@Test
public void login() throws Exception {
    Principal principal = new PrincipalImpl();

    mockMvc.perform(get("/login").principal(principal)).andExpect(.........;

}