Spring boot- inject service into doFiler

Question

I am trying to inject a auth service to a Filter -

@Autowired
AuthRequestService authService;

And use it in doFiler

Answer 1

Your filter is not under the control of spring. That´s why the autowired dependencies are not being injected.

In your filter init code add this line:

SpringBeanAutowiringSupport.processInjectionBasedOnCurrentContext(this);

or

SpringBeanAutowiringSupport.processInjectionBasedOnServletContext(this,getServletContext());

But there are more other ways to register a servlet filter in spring context: https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#boot-features-embedded-container-servlets-filters-listeners-beans

Answer 2

You could use constructor injection. Supposed your filter registration bean lives in a component and has access to the service you could autowire it there and pass it with the constructor

@Autowired  
AuthRequestService authRequestService;

[...]

FilterRegistrationBean<SAPServiceFilter> filterRegBean = new FilterRegistrationBean<>();
filterRegBean.setFilter(new SAPServiceFilter(authRequestService));