使用Mockito，GridFS，REST控制器进行Junit测试

Question

我正在为文件上传/下载休息服务编写junit测试。通过调用“gridFSBucket.find（eq（objectId））来运行到NPE。first（）;我从之前的帖子中知道Bson没有实现eq。所以，我一直在使用Document。我也尝试过使用Mockito的做法相反，返回方法，但似乎没有工作。感谢您的支持。

"doReturn(gridFSFindIterable).when(gridFSBucket).find(doc);"

FileRest设置参数

private MockMvc mockMvc;

  private Logger logger = LoggerFactory.getLogger(GridfsApplicationTests.class);

  @Spy
  GridFSBucket gridFSBucket;

  @Mock
  MongoConfig mongoConfig;

  @InjectMocks
  private FileUploadRestController fileUploadRestController;

  private GridFS gridFS;
  private GridFSFile gridFSFile;
  private GridFSDownloadStream gridFSDownloadStream;
  private MongoClient mongoClient;
  private GridFSFindIterable gridFSFindIterable;

  @Before
  public void Setup() {
    try {
      MockitoAnnotations.initMocks(this);
      mockMvc = MockMvcBuilders.standaloneSetup(fileUploadRestController).build();
      assertNotNull(mockMvc);
      fileLicense = new File(String.valueOf(path.toFile()));
      gridFS = mock(GridFS.class);
      mongoConfig = mock(MongoConfig.class);
      gridFSDownloadStream = mock(GridFSDownloadStream.class);
      mongoClient = mock(MongoClient.class);
      gridFSFile = mock(GridFSFile.class);
      gridFSFindIterable = mock(GridFSFindIterable.class);
    } catch (NullPointerException npe) {
      logger.warn("Unable to read file: {}", path, npe);
    }
    assertThat(fileLicense).exists();
  }

FindRestController端点

  @GetMapping("/find/")
  public ResponseEntity<?> findFile(@RequestParam("id") String id) {
    ObjectId objectId = new ObjectId(id);
    JSONObject jsonObject = new JSONObject();
    GridFSFile file = gridFSBucket.find(eq(objectId)).first();
    if (file != null) {
      HttpHeaders httpHeaders = new HttpHeaders();
      httpHeaders.setContentType(MediaType.APPLICATION_JSON);
      jsonObject.put("file", file.getId().toString());
      return new ResponseEntity<>(jsonObject.toString(), httpHeaders, HttpStatus.OK);
    }
    return new ResponseEntity<>(HttpStatus.NOT_FOUND);
  }

Junit测试用例查找：

  @Test
  public void testFindFile_givenObjectId_ReturnSuccessful() throws IOException {
    // given
    String id = "5c87b948ff03f91885cedb25";
    Document doc = new Document("test.txt", fileLicense);
    doc.append("id", id);

    Mockito.when(gridFSBucket.find(any(Bson.class))).thenReturn(gridFSFindIterable);
    Mockito.when(gridFSFindIterable.first()).thenReturn(gridFSFile);
    // when
    try {
      MockHttpServletRequestBuilder requestBuilder = MockMvcRequestBuilders
        .get("/fileupload/find/?id=5c87b948ff03f91885cedb25")
        .contentType(MediaType.APPLICATION_JSON)
        .accept("*");
      MvcResult result = mockMvc.perform(requestBuilder).andDo(print()).andReturn();
      MockHttpServletResponse response = result.getResponse();
      // then
      Assert.assertEquals("response status is wrong", 200, response.getStatus());
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

NPE错误：

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1013)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:897)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)
    at org.springframework.test.web.servlet.TestDispatcherServlet.service(TestDispatcherServlet.java:71)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
    at org.springframework.mock.web.MockFilterChain$ServletFilterProxy.doFilter(MockFilterChain.java:166)
    at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:133)
    at org.springframework.test.web.servlet.MockMvc.perform(MockMvc.java:182)
    at com.parsons.gridfs.GridfsApplicationTests.testFindFile_givenObjectId_ReturnSuccessful(GridfsApplicationTests.java:233)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.mockito.internal.runners.DefaultInternalRunner$1.run(DefaultInternalRunner.java:79)
    at org.mockito.internal.runners.DefaultInternalRunner.run(DefaultInternalRunner.java:85)
    at org.mockito.internal.runners.StrictRunner.run(StrictRunner.java:39)
    at org.mockito.junit.MockitoJUnitRunner.run(MockitoJUnitRunner.java:163)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: java.lang.NullPointerException
    at com.parsons.gridfs.FileUploadRestController.findFile(FileUploadRestController.java:120)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:189)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)
    ... 36 more

Answer 1

标记为已解决。我在我的响应中返回了文件对象，而不是GridFSFile的object.getId（）。toString（）;