class GitHubApiController {

    @GetMapping("user/{screenName}")
    public ResponseEntity<User> discoverUserByScreenName(@PathVariable("screenName")  String screenName) {
        return Optional.of(ResponseEntity.ok(gitHubService.discoverUserByScreenName(screenName)))
                .or(new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR));
    }

    @Autowired public  GitHubApiController(GitHubService gitHubService);

}