How to use #MockBean and MockMvc to append some data with HTTP POST to a mocked repository - spring

Question

I have a controller with a POST action, that creates a new BLOGPOST and return all the BLOGPOSTS including the newly created one:
#Autowired
private BlogPostInMemRepository bpr;
#RequestMapping(method = RequestMethod.POST, path="/post",
consumes = MediaType.APPLICATION_FORM_URLENCODED_VALUE)
public #ResponseBody List<BlogPost> addPost(BlogPost post) {
bpr.addPost(post);
return bpr.getAllPosts();
}
The BlogPostInMemRepository code looks like this:
#Repository
public class BlogPostInMemRepository {
private List<BlogPost> posts = new ArrayList<BlogPost>(){{
add(new BlogPost(1, "Author1", "Post 1"));
add(new BlogPost(2, "Author2", "Post 2"));
}};
public List<BlogPost> getAllPosts(){
return posts;
}
public void addPost(BlogPost post){
posts.add(post);
}
}
My goal is to unit test the controller using #MockBean and MockMvc. The steps would be:
Mock the BlogPostInMemRepository injecting some initial data into it
Issue a post request with mockMvc.perform(post("/api/v1/post")
Get back the initial post with the new post successfully added.
My current tests:
#Test
public void post_whenValidParametersPassed_addsAndReturnsAllBlogPostsSuccessfully() throws Exception {
// given
BlogPost bp1 = new BlogPost(1, "John", "Post 1");
BlogPost bp2 = new BlogPost(2, "Jack", "Post 2");
List<BlogPost> posts = new ArrayList<BlogPost>(){{ add(bp1); add(bp2); }};
given(repo.getAllPosts()).willReturn(posts);
mockMvc.perform(post("/api/v1/post")
.contentType(APPLICATION_FORM_URLENCODED)
.param("id", "33")
.param("author", "Gibraltar")
.param("post", "There is now way!"))
.andExpect(status().isOk())
.andExpect(content().string("{... the whole string ...}"))
.andDo(print());
}
What I get is just the posts passed in: given(repo.getAllPosts()).willReturn(posts); - which is expected, of course.
QUESTION: how to actually inject the initial set of BLOGPOSTS, add one more with POST and get all of them back from a mocked repository?

Answer 1

If you are planning to mock the repository it does not really make much sense to follow your approach as the addPost will have no effect and getAllPosts would just assume it has been added. It seems a bit artificial and not bring any real value testing-wise.
What I would do here is to use a simple in-order verification:
InOrder inOrder = Mockito.inOrder(brp);
inOrder.verify(brp).addPost(any(Post.class));
inOrder.verify(brp).getAllPosts();
So to make sure the post is added before all of them are fetched from the repo.

Answer 2

Solved it by using doCallRealMethod() and when().thenCallRealMethod() - this seems to be the only way to inject controller data from "down-below (bottom-up)" using Mockito, as direct setters do not work on #MockBean's.
Code:
#Test
public void post_whenValidParametersPassedAndPreExistingBlogsPresent_addsAndReturnsAllBlogPostSuccessfully() throws Exception {
// given : initialize mock data
BlogPost bp1 = new BlogPost(1, "John", "Post 1");
BlogPost bp2 = new BlogPost(2, "Jack", "Post 2");
List<BlogPost> posts = new ArrayList<BlogPost>(){{ add(bp1); add(bp2); }};
// given : prep the mocked object
doCallRealMethod().when(repo).setPosts(posts);
doCallRealMethod().when(repo).addPost(any(BlogPost.class));
repo.setPosts(posts);
when(repo.getAllPosts()).thenCallRealMethod();
mockMvc.perform(post("/api/v1/post")
.contentType(APPLICATION_FORM_URLENCODED) //from MediaType
.param("id", "33")
.param("author", "Gibraltar")
.param("post", "There is now way!"))
.andExpect(status().isOk())
.andExpect(content().string("[" +
"{\"id\":1,\"author\":\"John\",\"post\":\"Post 1\"}," +
"{\"id\":2,\"author\":\"Jack\",\"post\":\"Post 2\"}," +
"{\"id\":33,\"author\":\"Gibraltar\",\"post\":\"There is now way!\"}" +
"]"))
.andDo(print());
}