詳解SpringCloudNetflixZuul中的速率限制

<dependency>
 <groupId>org.springframework.cloud</groupId>
 <artifactId>spring-cloud-starter-netflix-zuul</artifactId>
</dependency>
<dependency>
 <groupId>com.marcosbarbero.cloud</groupId>
 <artifactId>spring-cloud-zuul-ratelimit</artifactId>
 <version>2.2.0.RELEASE</version>
</dependency>

@Controller
@RequestMapping("/greeting")
public class GreetingController {
 
 @GetMapping("/simple")
 public ResponseEntity<String> getSimple() {
  return ResponseEntity.ok("Hi!");
 }
 
 @GetMapping("/advanced")
 public ResponseEntity<String> getAdvanced() {
  return ResponseEntity.ok("Hello, how you doing?");
 }
}

zuul:
 routes:
 serviceSimple:
  path: /greeting/simple
  url: forward:/
 serviceAdvanced:
  path: /greeting/advanced
  url: forward:/
 ratelimit:
 enabled: true
 repository: JPA
 policy-list:
  serviceSimple:
  - limit: 5
   refresh-interval: 60
   type:
   - origin
  serviceAdvanced:
  - limit: 1
   refresh-interval: 2
   type:
   - origin
 strip-prefix: true

@Test
public void whenRequestNotExceedingCapacity_thenReturnOkResponse() {
 ResponseEntity<String> response = restTemplate.getForEntity(SIMPLE_GREETING, String.class);
 assertEquals(OK, response.getStatusCode());
 
 HttpHeaders headers = response.getHeaders();
 String key = "rate-limit-application_serviceSimple_127.0.0.1";
 
 assertEquals("5", headers.getFirst(HEADER_LIMIT + key));
 assertEquals("4", headers.getFirst(HEADER_REMAINING + key));
 assertEquals("60000", headers.getFirst(HEADER_RESET + key)); 
}

X-RateLimit-Limit-rate-limit-application_serviceSimple_127.0.0.1: 5

X-RateLimit-Remaining-rate-limit-application_serviceSimple_127.0.0.1: 4

X-RateLimit-Reset-rate-limit-application_serviceSimple_127.0.0.1: 60000

X-RateLimit-Limit-rate-limit-application_serviceSimple_127.0.0.1: 5

X-RateLimit-Remaining-rate-limit-application_serviceSimple_127.0.0.1: 3

X-RateLimit-Reset-rate-limit-application_serviceSimple_127.0.0.1: 57031

@Test
public void whenRequestExceedingCapacity_thenReturnTooManyRequestsResponse() throws InterruptedException {
 ResponseEntity<String> response = this.restTemplate.getForEntity(ADVANCED_GREETING, String.class);
 assertEquals(OK, response.getStatusCode());
  
 for (int i = 0; i < 2; i++) {
  response = this.restTemplate.getForEntity(ADVANCED_GREETING, String.class);
 }
 
 assertEquals(TOO_MANY_REQUESTS, response.getStatusCode());
 
 HttpHeaders headers = response.getHeaders();
 String key = "rate-limit-application_serviceAdvanced_127.0.0.1";
 
 assertEquals("1", headers.getFirst(HEADER_LIMIT + key));
 assertEquals("0", headers.getFirst(HEADER_REMAINING + key));
 assertNotEquals("2000", headers.getFirst(HEADER_RESET + key));
 
 TimeUnit.SECONDS.sleep(2);
 
 response = this.restTemplate.getForEntity(ADVANCED_GREETING, String.class);
 assertEquals(OK, response.getStatusCode());
}

X-RateLimit-Limit-rate-limit-application_serviceAdvanced_127.0.0.1: 1

X-RateLimit-Remaining-rate-limit-application_serviceAdvanced_127.0.0.1: 0

X-RateLimit-Reset-rate-limit-application_serviceAdvanced_127.0.0.1: 268

@Bean
public RateLimitKeyGenerator rateLimitKeyGenerator(RateLimitProperties properties,
 RateLimitUtils rateLimitUtils) {
 return new DefaultRateLimitKeyGenerator(properties, rateLimitUtils) {
  @Override
  public String key(HttpServletRequest request, Route route,
   RateLimitProperties.Policy policy) {
   return super.key(request, route, policy) + "_" + request.getMethod();
  }
 };
}

X-RateLimit-Limit-rate-limit-application_serviceSimple_127.0.0.1_GET: 5

@Bean
public RateLimiterErrorHandler rateLimitErrorHandler() {
 return new DefaultRateLimiterErrorHandler() {
  @Override
  public void handleSaveError(String key, Exception e) {
   <i>// implementation</i>
  }
 
  @Override
  public void handleFetchError(String key, Exception e) {
   <i>// implementation</i>
  }
 
  @Override
  public void handleError(String msg, Exception e) {
   <i>// implementation</i>
  }
 };
}