Spring OAuth2 - There is no client authentication. Try adding an appropriate authentication filter

Question

We have an application which is using spring-security-oauth2:1.0. I was trying to change it to a newer version, spring-security-oauth2:2.0.7.RELEASE

Answer 1

One of the problems of the following error, can be that authentication was not performed. I have encountered this problem with older implementation of Spring.

verify that:

TokenEndpoint -> postAccessToken method. Check if Principal is not null. If it is null it means that Basic Authroziation was not performed.

One of the solution to add filter was to use:

@Configuration
public class FilterChainInitializer extends AbstractSecurityWebApplicationInitializer {

}

More information about AbstractSecurityWebApplicationInitializer can be found in Spring docs