Testing Spring s RequestBody using Spring MockMVC

Question

I am trying to test a method that posts an object to the database using Spring s MockMVC framework   I ve constructed the test as follows    Test public void testInsertObject   throws Exception         String url   BASE URL     object        ObjectBean anObject   new ObjectBean        anObject setObjectId  33        anObject setUserId  4268321              more      Gson gson   new Gson        String json   gson toJson anObject        MvcResult result   this mockMvc perform              post url               contentType MediaType APPLICATION JSON               content json                andExpect status   isOk                 andReturn        The method I m testing uses Spring s  RequestBody to receive the ObjectBean  but the test always returns a 400 error    ResponseBody  RequestMapping     consumes  application json                       produces  application json                       method RequestMethod POST                      value   object   public ObjectResponse insertObject  RequestBody ObjectBean bean        this photonetService insertObject bean        ObjectResponse response   new ObjectResponse        response setObject bean        return response      The json created by gson in the test         objectId   33       userId   4268321            many more     The ObjectBean class  public class ObjectBean    private String objectId  private String userId        many more  public String getObjectId         return objectId     public void setObjectId String objectId        this objectId   objectId     public String getUserId         return userId     public void setUserId String userId        this userId   userId          many more     So my question is  how to I test this method using Spring MockMVC

User · Answer

The issue is that you are serializing your bean with a custom Gson object while the application is attempting to deserialize your JSON with a Jackson ObjectMapper (within MappingJackson2HttpMessageConverter).

If you open up your server logs, you should see something like

Exception in thread "main" com.fasterxml.jackson.databind.exc.InvalidFormatException: Can not construct instance of java.util.Date from String value '2013-34-10-10:34:31': not a valid representation (error: Failed to parse Date value '2013-34-10-10:34:31': Can not parse date "2013-34-10-10:34:31": not compatible with any of standard forms ("yyyy-MM-dd'T'HH:mm:ss.SSSZ", "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", "EEE, dd MMM yyyy HH:mm:ss zzz", "yyyy-MM-dd"))
 at [Source: java.io.StringReader@baea1ed; line: 1, column: 20] (through reference chain: com.spring.Bean["publicationDate"])

among other stack traces.

One solution is to set your Gson date format to one of the above (in the stacktrace).

The alternative is to register your own MappingJackson2HttpMessageConverter by configuring your own ObjectMapper to have the same date format as your Gson.

User · Answer

the following works for me     mockMvc perform              MockMvcRequestBuilders post   api test url                        contentType MediaType APPLICATION JSON                       content asJsonString createItemForm                 andExpect status   isCreated        public static String asJsonString final Object obj        try           return new ObjectMapper   writeValueAsString obj         catch  Exception e            throw new RuntimeException e

User · Answer

Use this one  public static final MediaType APPLICATION JSON UTF8   new MediaType MediaType APPLICATION JSON getType    MediaType APPLICATION JSON getSubtype    Charset forName  utf8       Test public void testInsertObject   throws Exception        String url   BASE URL     object       ObjectBean anObject   new ObjectBean        anObject setObjectId  33        anObject setUserId  4268321              more     ObjectMapper mapper   new ObjectMapper        mapper configure SerializationFeature WRAP ROOT VALUE  false       ObjectWriter ow   mapper writer   withDefaultPrettyPrinter        String requestJson ow writeValueAsString anObject         mockMvc perform post url  contentType APPLICATION JSON UTF8           content requestJson            andExpect status   isOk         As described in the comments  this works because the object is converted to json and passed as the request body  Additionally  the contentType is defined as Json  APPLICATION JSON UTF8     More info on the HTTP request body structure

User · Answer

I have encountered a similar problem with a more recent version of Spring  I tried to use a new ObjectMapper   writeValueAsString      but it would not work in my case  I actually had a String in a JSON format  but I feel like it is literally transforming the toString   method of every field into JSON  In my case  a date LocalDate field would end up as    quot date quot    quot year quot  2021  quot month quot   quot JANUARY quot   quot monthValue quot  1  quot dayOfMonth quot  1  quot chronology quot    quot id quot   quot ISO quot   quot calendarType quot   quot iso8601 quot    quot dayOfWeek quot   quot FRIDAY quot   quot leapYear quot  false  quot dayOfYear quot  1  quot era quot   quot CE quot    which is not the best date format to send in a request     In the end  the simplest solution in my case is to use the Spring ObjectMapper  Its behaviour is better since it uses Jackson to build your JSON with complex types   Autowired private ObjectMapper objectMapper   and I simply used it in mytest  mockMvc perform post  quot  api  quot                    content objectMapper writeValueAsString                        contentType MediaType APPLICATION JSON

[spring-mvc] Testing Spring's @RequestBody using Spring MockMVC

Examples related to spring-mvc

Examples related to integration-testing