Testing @RestController that returns a Page in Spring

Question

I have this restcontroller that returns paged items with:

    @GetMapping("/api/items")
    public Page<Item> getPagedItems(Pageable pageable, @RequestParam(defaultValue="") String searchBy, 
            @RequestParam(defaultValue="") String searchValue) {
        Page<Item> pageItem;

        switch (searchBy) {
        case "name" :
            pageItem = itemRepository.findByNameStartingWith(searchValue, pageable);
            break;
        case "description" :
            pageItem = itemRepository.findByDescriptionStartingWith(searchValue, pageable);
            break;  
        default:
            pageItem = itemRepository.findAll(pageable);    
            break;
        }   
        return pageItem;    
    }

So far my MvcTest looks like this:

    @Test
    public void testGetItems() throws Exception{  
      Page<Item> itemPage = itemRepository.findAll(PageRequest.of(0, 20));

      given(itemRepository.findAll(PageRequest.of(0, 20))).willReturn(itemPage)
      this.mvc.perform(get("/api/items")
       .contentType(MediaType.APPLICATION_JSON))
       .andDo(print())
       .andExpect(status().isOk())
       .andExpect(jsonPath("$",hasSize(1)));
    }

I want the contents of this /api/items request. It is returning

java.lang.AssertionError: No value at JSON path "$" at org.springframework.test.util.JsonPathExpectationsHelper.evaluateJsonPath(JsonPathExpectationsHelper.java:290) at org.springframework.test.util.JsonPathExpectationsHelper.assertValue(JsonPathExpectationsHelper.java:74) at org.springframework.test.web.servlet.result.JsonPathResultMatchers.lambda$value$0(JsonPathResultMatchers.java:87) at org.springframework.test.web.servlet.MockMvc$1.andExpect(MockMvc.java:179) at com.eprocurement.ItemRestMvcTest.testGetItems(ItemRestMvcTest.java:60) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) 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.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:73) at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:83) at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75) at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86) at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97) 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.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206) Caused by: java.lang.IllegalArgumentException: json can not be null or empty at com.jayway.jsonpath.internal.Utils.notEmpty(Utils.java:386) at com.jayway.jsonpath.JsonPath.read(JsonPath.java:342) at com.jayway.jsonpath.JsonPath.read(JsonPath.java:329) at org.springframework.test.util.JsonPathExpectationsHelper.evaluateJsonPath(JsonPathExpectationsHelper.java:287) ... 35 more

What can I do to make this test work? What seems to be the problems?

If it helps also I'm using Spring Security. I've annotated the test class with @WithMockUser(roles="ADMIN").

K. Siva Prasad Reddy K. Siva Prasad Reddy · Accepted Answer · 2018-04-11T03:00:45

When you return Page<Item> as a response, the response JSON would be something like:

{
  content: [
    {
      id: 1,
      name: "abc"
    },
    {
      id: 2,
      name: "xyz"
    }
  ],
  pageable: {
    sort: {
      sorted: false,
      unsorted: true
    },
    offset: 0,
    pageSize: 10,
    pageNumber: 0,
    paged: true,
    unpaged: false
  },
  last: true,
  totalPages: 1,
  totalElements: 2,
  size: 10,
  number: 0,
  first: true,
  numberOfElements: 2,
  sort: {
    sorted: false,
    unsorted: true
  }
}

So, your assertion path should be $.content like .andExpect(jsonPath("$.content",hasSize(1)));

Testing @RestController that returns a Page in Spring

1 Answers