Autowired HttpServletRequest in Spring-test integration tests

Question

I am trying to do a test to cover login functionality. Version of Spring is 3.2.12. I have a session bean, declared as:

@Service
@Scope(value = "session", proxyMode = ScopedProxyMode.INTERFACES)
public class ClientSessionServiceImpl implements ClientSessionService {
    @Autowired
    private HttpServletRequest request;
    // This method is called during the login routine from the filter
    public boolean checkUser() {
    // I rely on request attributes here, which were set in the filter
    }

This works perfectly when run on the server, but when run with the means of spring-test, the problem comes. This is my test method:

this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).addFilter(springSecurityFilterChain).build();
mockMvc.perform(post(URL));

After debugging, i found out, that when test spring context is started, in the ServletTestExecutionListener.setUpRequestContextIfNecessary an instance of MockHttpServletRequest is created, MockHttpServletRequest request = new MockHttpServletRequest(mockServletContext);
 // Lets' call this instance A. And this is the instance that's get injected everywhere, i use

@Autowired
HttpServletRequest request;

Whereas, calling MockMvc.perform, creates another instance of MockHttpServletRequest (Let's call it instance B), which is passed to all the filters, servlets, etc. So, basically, the attribute i set in the filter in the request, can't be read in the ClientSessionServiceImpl, because different instance of MockHttpServletRequest is injected there.

I spent bunch of time on this, but still have not found the solution.

P.S. I searched through StackOverflow, there are questions with similar titles, but describing the problems that differ from mine, as i don't want to pass HttpServletRequest as a parameter, and would prefer to have it Autowired, unless there is a good reason for it.

Answer 1

So, basically, the attribute i set in the filter in the request, can't be read in the ClientSessionServiceImpl, because different instance of MockHttpServletRequest is injected there.

This is a timing issue with regard to when Spring's RequestAttributes are populated in the RequestContextHolder. In production I would assume that you are configuring either a RequestContextFilter or a RequestContextListener.

In any case, manually adding an instance of RequestContextFilter to the front of the filter chain in your test will solve the problem.

mockMvc = MockMvcBuilders
  .webAppContextSetup(this.wac)
  .addFilters(new RequestContextFilter(), testFilterChain)
  .build();

Please note that this will become the default behavior in Spring Framework 4.2: code that simulates RequestContextFilter will be implemented directly in MockMvc. See JIRA issue SPR-13217 for details.

---

As an aside, configuring the MockHttpServletRequest that is created by the ServletTestExecutionListener is not supported. If you are using MockMvc it is expected that you configure the mocked request via the RequestBuilders.

However, having said that, if you have a concrete need for modifying the mock request created by ServletTestExecutionListener manually and then having that re-used with MockMvc, you can create the following class in your project:

package org.springframework.test.web.servlet.request;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;

import org.springframework.http.HttpMethod;
import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

/**
 * Patched version of {@link MockHttpServletRequestBuilder}.
 *
 * @author Sam Brannen
 * @since 4.2
 */
public class PatchedMockHttpServletRequestBuilder extends MockHttpServletRequestBuilder {

    public static MockHttpServletRequestBuilder get(String urlTemplate, Object... urlVariables) {
        return new PatchedMockHttpServletRequestBuilder(HttpMethod.GET, urlTemplate, urlVariables);
    }

    public PatchedMockHttpServletRequestBuilder(HttpMethod httpMethod, String urlTemplate, Object... urlVariables) {
        super(httpMethod, urlTemplate, urlVariables);
    }

    /**
     * Create a {@link MockHttpServletRequest}.
     * <p>If an instance of {@code MockHttpServletRequest} is available via
     * the {@link RequestAttributes} bound to the current thread in
     * {@link RequestContextHolder}, this method simply returns that instance.
     * <p>Otherwise, this method creates a new {@code MockHttpServletRequest}
     * based on the supplied {@link ServletContext}.
     * <p>Can be overridden in subclasses.
     * @see RequestContextHolder#getRequestAttributes()
     * @see ServletRequestAttributes
     */
    @Override
    protected MockHttpServletRequest createServletRequest(ServletContext servletContext) {
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
        if (requestAttributes instanceof ServletRequestAttributes) {
            HttpServletRequest request = ((ServletRequestAttributes) requestAttributes).getRequest();
            if (request instanceof MockHttpServletRequest) {
                return (MockHttpServletRequest) request;
            }
        }

        return new MockHttpServletRequest(servletContext);
    }

}

Note: it must be in the org.springframework.test.web.servlet.request package; otherwise, it can't extend MockHttpServletRequestBuilder which is required.

Then, use the get() method from PatchedMockHttpServletRequestBuilder instead of from MockMvcRequestBuilders, and everything should work as you expect!

Obviously, the above example re-implements get(), but you can naturally do the same for post(), etc.

FYI: I might eventually commit the above patched version of createServletRequest() to Spring Framework 4.2.x (see JIRA issue SPR-13211).

Regards,

Sam (author of the Spring TestContext Framework)