How to add accessToken authentication in Zuul API Gateway? - spring-boot

Question

I would like to authenticate all the requests at Zuul Gateway. i,e., each API request will send accessToken and zuul should authenticate the accessToken.
I have implemented this by extending ZuulFilter.
My code is below:
#Component
public class ZuulPreFilter extends ZuulFilter {
#Autowired
private DiscoveryClient discoveryClient;
#Override
public String filterType() {
return PRE_TYPE;
}
#Override
public int filterOrder() {
return PRE_DECORATION_FILTER_ORDER + 1;
}
#Override
public boolean shouldFilter() {
return true;
}
#Override
public Object run() {
RequestContext ctx = RequestContext.getCurrentContext();
HttpServletRequest request = ctx.getRequest();
String accessToken = request.getParameter("accessToken");
if (accessToken == null || accessToken.isEmpty()) {
return sendUnauthorizedResponse(ctx, request, "Required AccessToken");
}
List<ServiceInstance> instances = this.discoveryClient.getInstances("security_service");
if (instances != null && instances.size() > 0) {
ServiceInstance securityService = instances.get(0);
String authAccessTokenAPI = securityService.getUri().toString().concat("/users/?accessToken=")
.concat(accessToken);
RestTemplate restTemplate = new RestTemplate();
ResponseEntity<ValidationResponse> response = restTemplate.getForEntity(authAccessTokenAPI,
ValidationResponse.class);
ValidationResponse authUserResponse = response.getBody();
if (authUserResponse == null || !authUserResponse.isSuccess()) {
return sendUnauthorizedResponse(ctx, request, "Invalid AccessToken");
}
}
return null;
}
private Object sendUnauthorizedResponse(RequestContext ctx, HttpServletRequest request, String responseMessage) {
ctx.setSendZuulResponse(false);
ctx.setResponseStatusCode(HttpStatus.UNAUTHORIZED.value());
ValidationResponse validationResponse = new ValidationResponse();
validationResponse.setSuccess(false);
validationResponse.setMessage(responseMessage);
String contentType = request.getContentType();
if (contentType == null) {
contentType = MediaType.APPLICATION_JSON;
}
// To handle Json contentType
if (contentType.equalsIgnoreCase(MediaType.APPLICATION_JSON)) {
ObjectMapper mapper = new ObjectMapper();
try {
String responseBody = mapper.writeValueAsString(validationResponse);
ctx.setResponseBody(responseBody);
ctx.getResponse().setContentType(MediaType.APPLICATION_JSON);
} catch (JsonProcessingException e) {
}
}
// To handle XML contentType
if (contentType.equalsIgnoreCase(MediaType.APPLICATION_XML)) {
String responseBody = XmlUtil.marshal(validationResponse);
ctx.setResponseBody(responseBody);
ctx.getResponse().setContentType(MediaType.APPLICATION_XML);
}
return ctx;
}
}
I felt its NOT an effective way. Is there any other way to implement this scenario ?
Thanks.