这是我的控制器：

@PostMapping("post")
@PreAuthorize("hasAuthority('WRITE')")
public ResponseEntity<?> createPost(@RequestBody PostEntity postEntity) {
    return new ResponseEntity<>(postService.createPost(postEntity), HttpStatus.CREATED);
}

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服务内容：

@Override
public Post createPost(PostEntity postEntity) {
    return postFactory.buildPost(postEntityRepository.save(postEntity));
}

//Post is Immutable class here
    public Post buildPost(PostEntity entity) {
        return new Post.Builder()
                .groupId(entity.getGroupEntity().getGroupId())
                .postedBy(entity.getPostedBy().getUsername())
                .postType(entity.getType())
                .postMedia(entity.getPostMedia())
                .postId(entity.getPostId())
                .build();
    }

型
下面是我的mockMvc：

@BeforeEach
public void setUp(WebApplicationContext webApplicationContext,
                  RestDocumentationContextProvider restDocumentation) {
    this.mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext)
            .apply(documentationConfiguration(restDocumentation))
            .alwaysDo(document("{method-name}",
                    preprocessRequest(prettyPrint()), preprocessResponse(prettyPrint())))
            .build();
}

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以下是我的测试：

this.mockMvc.perform(post("/api/post")
            .contentType(MediaTypes.HAL_JSON)
            .contextPath("/api")
            .content(this.objectMapper.writeValueAsString(postEntity)))
            .andExpect(status().isCreated())
            .andDo(
                    document("{method-name}", preprocessRequest(prettyPrint()),
                            preprocessResponse(prettyPrint()),
                            requestFields(describeCreatePostRequest()),
                            responseFields(describePostEntityResult())
                    ));

型
下面是Post call：

@Value.Immutable
@JsonSerialize(as = ImmutablePost.class)
@JsonDeserialize(as = ImmutablePost.class)
@JsonInclude(JsonInclude.Include.NON_NULL)
@Relation(value = "post", collectionRelation = "posts")
public interface Post {

    Long getPostId();

    String getPostType();

    String postedBy();

    @Nullable
    PostMedia postMedia();

    Long groupId();

    class Builder extends ImmutablePost.Builder {}
}

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PostEntity @Entity类这里是json格式：

{
        "type" : "text",
        "postedBy" : {
                "username": "sandeep"
        },
        "postMedia" : {
            "mediaType": "text",
            "mediaUrl": "null",
            "content": "Hi this is testing media content",
            "createdAt": 1234,
            "updatedAt": 689
        },
        "groupEntity": {
            "groupId": 4
        }
    }

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Post实体类：

@Entity
 @Table(name = "POST")
 @JsonIgnoreProperties({"hibernateLazyInitializer", "handler"})
public class PostEntity {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "POST_ID")
private Long postId;

@Column(name = "POST_TYPE")
private String type;

@ManyToOne
@JoinColumn(name = "username", referencedColumnName = "username")
private User postedBy;

@OneToOne(cascade = CascadeType.ALL, fetch = FetchType.LAZY)
@JoinColumn(name = "post_media_id", referencedColumnName = "id")
private PostMedia postMedia;

@ManyToOne(cascade = CascadeType.REMOVE, fetch = FetchType.LAZY)
@JoinColumn(name = "GROUP_ID", referencedColumnName = "GROUP_ID")
private GroupEntity groupEntity;
public PostEntity() {
}

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}
我已经尝试

objectMapper.readValue(objectMapper.writeValueAsString(postEntity), ImmutablePost.class);

型
同样，但它仍然不工作，我面临着同样的例外：

org.springframework.restdocs.snippet.SnippetException: Cannot document response fields as the response body is empty

at org.springframework.restdocs.payload.AbstractFieldsSnippet.verifyContent(AbstractFieldsSnippet.java:191)
at org.springframework.restdocs.payload.AbstractFieldsSnippet.createModel(AbstractFieldsSnippet.java:147)
at org.springframework.restdocs.snippet.TemplatedSnippet.document(TemplatedSnippet.java:78)
at org.springframework.restdocs.generate.RestDocumentationGenerator.handle(RestDocumentationGenerator.java:191)

型