NullPointer trying to get user info with Keycloak in Spring Boot-CodePudding

I am using Keycloak in my REST application with spring-boot. It works correctly, I have defined roles in Keycloak, then in my Config.class I allow access to the end-points that interest me according to the role of each user. I have the problem when trying to retrieve the user information in my back (name, principal, authorities...).

I have read various SO POSTS like these:

Does anyone know why I get null when trying to access SecurityContext? My goal is to retrieve user data

CodePudding user response：

You are initializing the securityContext object in your controller when the controller is first created:

private SecurityContext securityContext = SecurityContextHolder.getContext();

At that time, there is no security context available, meaning that the context is always null.

Don't use a private variable in a controller to store the context, instead, fetch it from the SecurityContextHolder in the getLicenses method:

@GetMapping(value = "/getLicenses")
public ResponseEntity<List<License>> getLicenses() {
    SecurityContext securityContext = SecurityContextHolder.getContext();
    System.out.println("SecurityContext: "   securityContext);
    System.out.println("Authentication securityContext: "   securityContext.getAuthentication());
    return new ResponseEntity<List<License>>(licenseService.getLicenses(), null, HttpStatus.OK);
}