Unit Testing 'Location' header of Spring REST Controller

Question

After creating a resource in Spring REST Controller , I am returning it's location in header as below.

@RequestMapping(..., method = RequestMethod.POST)
public ResponseEntity<Void> createResource(..., UriComponentsBuilder ucb) {

    ...

    URI locationUri = ucb.path("/the/resources/")
        .path(someId)
        .build()
        .toUri();

    return ResponseEntity.created(locationUri).build();
}

In Unit Test, I am checking its location as below.

@Test
public void testCreateResource(...) {
    ...
    MockHttpServletRequestBuilder request = post("...")
        .content(...)
        .contentType(MediaType.APPLICATION_JSON)
        .accept(MediaType.APPLICATION_JSON);

    request.session(sessionMocked);

    mvc.perform(request)
        .andExpect(status().isCreated())
        .andExpect(header().string("Location", "/the/resources" + id);
}

This result cases fails with following message.

java.lang.AssertionError: Response header Location expected:</the/resources/123456> but was:<http://localhost/the/resources/123456>

Seems like I have to provide context prefix http://localhost for Location header in expectation.

• Is it safe to hard code context? If so, why?
• If not, what is right way to generate it correctly for test case?

Answer 1

I'm guessing because you are using UriComponentsBuilder to build your URI it's setting the host name in your location header. Had you used something like just new URI("/the/resources"), your test would have passed.

In your case, I'd use redirectedUrlPattern to match the redirection URL:

.andExpect(redirectedUrlPattern("http://*/the/resources"))

This will match any hostname, so you don't have to hardcode localhost. Learn more about different patterns that you can use with AntPathMatcherhere.