MockHttpServletRequest changes Accept-Language header values [SPR-17566]

[spring-projects-issues]

Jan Engehausen opened SPR-17566 and commented

Greetings,

after switching to Spring 5 (via Spring Boot 2) I am unhappy with the behaviour of org.springframework.mock.web.MockHttpServletRequest in regards to handling the Accept-Language header. It seems that it is getting manipulated when values for this header are set. In short, I potentially do not get back the value I am setting. If I set a literal value, e.g. ru, fr;q=0.5, *;q=0.1 then I expect to get this back when I read it again. However, it gets transformed into e.g. ru, fr.

I am attaching a test showing the issue.

While I might work around this by subclassing the mock request where used directly, when I use fancier things like org.springframework.test.web.servlet.MockMvc this does not work (at least I don't know how). The request is built internally, and my code using that request sees the above demonstrated unexpected value.

public void testSomething() throws Exception {
 mockMvc.perform(
 get("/my/controller/url")
 .header(HttpHeaders.ACCEPT_LANGUAGE, "ru, fr;q=0.5, *;q=0.1")
 )
 .andExpect(status().isOk());
) 

Suggestions on how to circumvent this problem or a fix would be appreciated!

Thanks,
Jan

---

Affects: 5.0.11, 5.1.3

Attachments:

• lang-tag-demo.zip (3.62 kB)

Issue Links:

• MockHttpServletRequest.addHeader fails for invalid LanguageRange in Accept-Language [SPR-16454] #20999 MockHttpServletRequest.addHeader fails for invalid LanguageRange in Accept-Language
• Mock MVC / RequestBuilder should handle Accept-Language header appropriately [SPR-15209] #19773 Mock MVC / RequestBuilder should handle Accept-Language header appropriately

Backported to: 5.0.12

[spring-projects-issues]

Juergen Hoeller commented

Fixed through preserving the original Accept-Language header value now, in addition to parsing the preferred locales.

[spring-projects-issues]

Jan Engehausen commented

Thanks Juergen, that was a light speed job :) (y)!