Can you add SPeL in @Spec constVal with value from headers?

[sanjeevghimire]

Can you add SPeL in @Spec constVal with value from headers?

[tkaczmarzyk]

specification-arg-resolver uses Spring's EmbeddedValueResolver. It basically wrapps provided AbstractApplicationContext:

 new EmbeddedValueResolver(applicationContext.getBeanFactory())

After quick look, I don't see an option to resolve your expression via this component (but maybe I'm missing something).

What did work for me is the following:

1. Define a RequestScoped bean which has access to the current HttpServletRequest (and therefore can access any http header):

public class HeaderHolder {

	@Autowired
	  private HttpServletRequest httpServletRequest;
	
	public Object getHeader() {
		return httpServletRequest.getHeader("myHeaderName");
	}
}

2. use "@" notation to access this bean in you SpEL: #{@headerHolder.header}

Please note that it was just a quick try and I did not evaluated this approach thoroughly -- just checked and expression was properly evaluated.

[tkaczmarzyk]

Actually, also please observe this PR: #133 which contains direct header support