深入学习spring cloud gateway 限流熔断
前言
Spring Cloud Gateway
目前，Spring Cloud Gateway是仅次于Spring Cloud Netflix的第二个最受欢迎的Spring Cloud项目（就GitHub上的星级而言）。它是作为Spring Cloud系列中Zuul代理的继任者而创建的。该项目提供了用于微服务体系结构的API网关，并基于反应式Netty和Project Reactor构建。它旨在提供一种简单而有效的方法来路由到API并解决诸如安全性，监视/度量和弹性之类的普遍关注的问题。
基于Redis限流
Spring Cloud Gateway为您提供了许多功能和配置选项。今天，我将集中讨论网关配置的一个非常有趣的方面-速率限制。速率限制器可以定义为一种控制网络上发送或接收的流量速率的方法。我们还可以定义几种类型的速率限制。Spring Cloud Gateway当前提供了一个Request Rate Limiter，它负责将每个用户每秒限制为N个请求。与Spring Cloud Gateway一起 使用时RequestRateLimiter，我们可能会利用Redis。Spring Cloud实现使用令牌桶算法做限速。该算法具有集中式存储桶主机，您可以在其中对每个请求获取令牌，然后将更多的令牌缓慢滴入存储桶中。如果存储桶为空，则拒绝该请求。
项目演示源码地址：https://github.com/1ssqq1lxr/SpringCloudGatewayTest
引入maven依赖
## spring cloud依赖
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.1.RELEASE</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>11</java.version>
<spring-cloud.version>Hoxton.RC2</spring-cloud.version>
</properties>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
## gateway 依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis-reactive</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.testcontainers</groupId>
<artifactId>mockserver</artifactId>
<version>1.12.3</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mock-server</groupId>
<artifactId>mockserver-client-java</artifactId>
<version>3.10.8</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.carrotsearch</groupId>
<artifactId>junit-benchmarks</artifactId>
<version>0.7.2</version>
<scope>test</scope>
</dependency>
限流器配置
使用Spring Cloud Gateway默认请求限流GatewayFilter（org.springframework.cloud.gateway.filter.ratelimit.RedisRateLimiter）。使用默认的Redis限流器方案，你可以通过自定义keyResolver类去决定Redis限流key的生成，下面举常用几个例子：
- 根据用户： 使用这种方式限流，请求路径中必须携带userId参数
@Bean
KeyResolver userKeyResolver() {
return exchange -> Mono.just(exchange.getRequest().getQueryParams().getFirst("userId"));
}
- 根据获uri
@Bean
KeyResolver apiKeyResolver() {
return exchange -> Mono.just(exchange.getRequest().getPath().value());
}
由于我们已经讨论了Spring Cloud Gateway速率限制的一些理论方面，因此我们可以继续进行实施。首先，让我们定义主类和非常简单的KeyResolverbean，它始终等于一个。
@SpringBootApplication
public class GatewayApplication {
public static void main(String[] args) {
SpringApplication.run(GatewayApplication.class, args);
}
@Bean
KeyResolver userKeyResolver() {
return exchange -> Mono.just("1");
}
}
Gateway默认使用org.springframework.cloud.gateway.filter.ratelimit.RedisRateLimiter限流器。 现在，如通过模拟Http请求，则会收到以下响应。它包括一些特定的header，其前缀为x-ratelimit。
- x-ratelimit-burst-capacity：最大令牌值，
- x-ratelimit-replenish-rate：填充的速率值，
- x-ratelimit-remaining：剩下可请求数。
yaml配置：
server:
port: ${PORT:8085}
spring:
application:
name: gateway-service
redis:
host: localhost
port: 6379
cloud:
gateway:
routes:
- id: account-service
uri: http://localhost:8091
predicates:
- Path=/account/**
filters:
- RewritePath=/account/(?.*), /$\{path}
- name: RequestRateLimiter
args:
redis-rate-limiter.replenishRate: 10
redis-rate-limiter.burstCapacity: 20
Redis限流器实现
关键源码如下：
// routeId也就是我们的服务路由id，id就是限流的key
public Mono<Response> isAllowed(String routeId, String id) {
// 会判断RedisRateLimiter是否初始化了
if (!this.initialized.get()) {
throw new IllegalStateException("RedisRateLimiter is not initialized");
}
// 获取routeId对应的限流配置
Config routeConfig = getConfig().getOrDefault(routeId, defaultConfig);
if (routeConfig == null) {
throw new IllegalArgumentException("No Configuration found for route " + routeId);
}
// 允许用户每秒做多少次请求
int replenishRate = routeConfig.getReplenishRate();
// 令牌桶的容量，允许在一秒钟内完成的最大请求数
int burstCapacity = routeConfig.getBurstCapacity();
try {
// 限流key的名称（request_rate_limiter.{localhost}.timestamp，request_rate_limiter.{localhost}.tokens）
List<String> keys = getKeys(id);
// The arguments to the LUA script. time() returns unixtime in seconds.
List<String> scriptArgs = Arrays.asList(replenishRate + "", burstCapacity + "",
Instant.now().getEpochSecond() + "", "1");
// allowed, tokens_left = redis.eval(SCRIPT, keys, args)
// 执行LUA脚本
Flux<List<Long>> flux = this.redisTemplate.execute(this.script, keys, scriptArgs);
// .log("redisratelimiter", Level.FINER);
return flux.onErrorResume(throwable -> Flux.just(Arrays.asList(1L, -1L)))
.reduce(new ArrayList<Long>(), (longs, l) -> {
longs.addAll(l);
return longs;
}) .map(results -> {
boolean allowed = results.get(0) == 1L;
Long tokensLeft = results.get(1);
Response response = new Response(allowed, getHeaders(routeConfig, tokensLeft));
if (log.isDebugEnabled()) {
log.debug("response: " + response);
}
return response;
});
}
catch (Exception e) {
log.error("Error determining if user allowed from redis", e);
}
return Mono.just(new Response(true, getHeaders(routeConfig, -1L)));
}
测试Redis限流器
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.DEFINED_PORT)
@RunWith(SpringRunner.class)
public class GatewayRateLimiterTest {
private static final Logger LOGGER = LoggerFactory.getLogger(GatewayRateLimiterTest.class);
@Rule
public TestRule benchmarkRun = new BenchmarkRule();
@ClassRule
public static MockServerContainer mockServer = new MockServerContainer();
@ClassRule
public static GenericContainer redis = new GenericContainer("redis:5.0.6").withExposedPorts(6379);
@Autowired
TestRestTemplate template;
@BeforeClass
public static void init() {
System.setProperty("spring.cloud.gateway.routes[0].id", "account-service");
System.setProperty("spring.cloud.gateway.routes[0].uri", "http://localhost:" + mockServer.getServerPort());
System.setProperty("spring.cloud.gateway.routes[0].predicates[0]", "Path=/account/**");
System.setProperty("spring.cloud.gateway.routes[0].filters[0]", "RewritePath=/account/(?<path>.*), /$\\{path}");
System.setProperty("spring.cloud.gateway.routes[0].filters[1].name", "RequestRateLimiter");
System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.redis-rate-limiter.replenishRate", "10");
System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.redis-rate-limiter.burstCapacity", "20");
System.setProperty("spring.redis.host", "localhost");
System.setProperty("spring.redis.port", "" + redis.getMappedPort(6379));
new MockServerClient(mockServer.getContainerIpAddress(), mockServer.getServerPort())
.when(HttpRequest.request()
.withPath("/1"))
.respond(response()
.withBody("{\"id\":1,\"number\":\"1234567890\"}")
.withHeader("Content-Type", "application/json"));
}
@Test
@BenchmarkOptions(warmupRounds = 0, concurrency = 6, benchmarkRounds = 600)
public void testAccountService() {
ResponseEntity<Account> r = template.exchange("/account/{id}", HttpMethod.GET, null, Account.class, 1);
LOGGER.info("Received: status->{}, payload->{}, remaining->{}", r.getStatusCodeValue(), r.getBody(), r.getHeaders().get("X-RateLimit-Remaining"));
// Assert.assertEquals(200, r.getStatusCodeValue());
// Assert.assertNotNull(r.getBody());
// Assert.assertEquals(Integer.valueOf(1), r.getBody().getId());
// Assert.assertEquals("1234567890", r.getBody().getNumber());
}
}
执行Test类： 发现超过20之后会被拦截返回429,运行过程中随着令牌的放入会不断有请求成功。
14:20:32.242 --- [pool-2-thread-1] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[18]
14:20:32.242 --- [pool-2-thread-4] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[16]
14:20:32.242 --- [pool-2-thread-2] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[14]
14:20:32.242 --- [pool-2-thread-3] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[15]
14:20:32.242 --- [pool-2-thread-6] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[17]
14:20:32.242 --- [pool-2-thread-5] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[19]
14:20:32.294 --- [pool-2-thread-4] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[15]
14:20:32.297 --- [pool-2-thread-6] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[19]
14:20:32.304 --- [pool-2-thread-3] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[18]
14:20:32.308 --- [pool-2-thread-5] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[16]
14:20:32.309 --- [pool-2-thread-1] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[17]
14:20:32.312 --- [pool-2-thread-2] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[14]
14:20:32.320 --- [pool-2-thread-4] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[13]
14:20:32.326 --- [pool-2-thread-6] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[12]
14:20:32.356 --- [pool-2-thread-4] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[7]
14:20:32.356 --- [pool-2-thread-5] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[10]
14:20:32.361 --- [pool-2-thread-6] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[6]
14:20:32.363 --- [pool-2-thread-2] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[8]
14:20:32.384 --- [pool-2-thread-5] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[4]
14:20:32.384 --- [pool-2-thread-3] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[11]
14:20:32.386 --- [pool-2-thread-4] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[5]
14:20:32.390 --- [pool-2-thread-1] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[9]
14:20:32.391 --- [pool-2-thread-6] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[3]
14:20:32.392 --- [pool-2-thread-2] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[2]
14:20:32.403 --- [pool-2-thread-6] : Received: status->429, payload->null, remaining->[0]
14:20:32.403 --- [pool-2-thread-4] : Received: status->429, payload->null, remaining->[0]
........
14:20:33.029 --- [pool-2-thread-2] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[9]
14:20:33.033 --- [pool-2-thread-1] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[8]
14:20:33.033 --- [pool-2-thread-4] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[7]
14:20:33.037 --- [pool-2-thread-3] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[6]
14:20:33.039 --- [pool-2-thread-5] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[5]
14:20:33.046 --- [pool-2-thread-6] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[4]
14:20:33.052 --- [pool-2-thread-5] : Received: status->429, payload->null, remaining->[0]
14:20:33.058 --- [pool-2-thread-6] : Received: status->429, payload->null, remaining->[0]
14:20:33.058 --- [pool-2-thread-1] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[2]
14:20:33.060 --- [pool-2-thread-5] : Received: status->429, payload->null, remaining->[0]
14:20:33.081 --- [pool-2-thread-4] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[1]
14:20:33.082 --- [pool-2-thread-3] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[0]
14:20:33.084 --- [pool-2-thread-2] : Received: status->200, payload->Account(id=1, number=1234567890), remaining->[3]
14:20:33.088 --- [pool-2-thread-5] : Received: status->429, payload->null, remaining->[0]
如果默认的限流器不能够满足使用，可以通过继承AbstractRateLimiter实现自定义限流器，然后通过RouteLocator方式去注入拦截器。
Resilience4J熔断器
引入依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-cloud-starter-circuitbreaker-reactor-resilience4j</artifactId>
</dependency>
Resilience4J 断路器介绍
三个一般性状态
- CLOSED：关闭状态，放过所有请求，记录请求状态。
- OPEN：打开，异常请求达到阀值数量时，开启熔断，拒绝所有请求。
- HALF_OPEN：半开，放开一定数量的请求，重新计算错误率。
两个特定状态
- DISABLED：禁用
- FORCED_OPEN：强开
状态之间转换
启动时断路器为CLOSE状态，在达到一定请求量至后计算请求失败率，达到或高于指定失败率后，断路进入open状态，阻拦所有请求，开启一段时间（自定义）时间后，断路器变为halfOpen状态，重新计算请求失败率。halfOpen错误率低于指定失败率后，断路进入close状态，否则进入open状态。
状态转换
通过Resilience4J启用Spring Cloud Gateway断路器
要启用构建在Resilience4J之上的断路器，我们需要声明一个Customizer传递了的bean ReactiveResilience4JCircuitBreakerFactory。可以非常简单地去配置设置，下面使用默认配置进行测试
@Bean
public Customizer<ReactiveResilience4JCircuitBreakerFactory> defaultCustomizer() {
return factory -> factory.configureDefault(id -> new Resilience4JConfigBuilder(id)
.circuitBreakerConfig(CircuitBreakerConfig.custom()
//统计失败率的请求总数
.slidingWindowSize(5)
//在半开状态下请求的次数
.permittedNumberOfCallsInHalfOpenState(5)
//断路器打开的成功率
.failureRateThreshold(50.0F)
//断路器打开的周期
.waitDurationInOpenState(Duration.ofMillis(30))
//属于慢请求的周期
.slowCallDurationThreshold(Duration.ofMillis(200))
//慢请求打开断路器的成功率
.slowCallRateThreshold(50.0F)
.build())
.timeLimiterConfig(TimeLimiterConfig.custom().timeoutDuration(Duration.ofMillis(200)).build()).build());
}
测试Resilience4J断路器
使用默认配置进行测试
@Bean
public Customizer<ReactiveResilience4JCircuitBreakerFactory> defaultCustomizer() {
return factory -> factory.configureDefault(id -> new Resilience4JConfigBuilder(id)
.circuitBreakerConfig(CircuitBreakerConfig.ofDefaults())
.circuitBreakerConfig(CircuitBreakerConfig.custom()
.slowCallDurationThreshold(Duration.ofMillis(200))
.build())
.timeLimiterConfig(TimeLimiterConfig.custom().timeoutDuration(Duration.ofMillis(200)).build())
.build());
}
执行下面Test用例
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.DEFINED_PORT)
@RunWith(SpringRunner.class)
public class GatewayCircuitBreakerTest {
private static final Logger LOGGER = LoggerFactory.getLogger(GatewayRateLimiterTest.class);
@Rule
public TestRule benchmarkRun = new BenchmarkRule();
@ClassRule
public static MockServerContainer mockServer = new MockServerContainer();
@Autowired
TestRestTemplate template;
final Random random = new Random();
int i = 0;
@BeforeClass
public static void init() {
System.setProperty("logging.level.org.springframework.cloud.gateway.filter.factory", "TRACE");
System.setProperty("spring.cloud.gateway.routes[0].id", "account-service");
System.setProperty("spring.cloud.gateway.routes[0].uri", "http://localhost:" + mockServer.getServerPort());
System.setProperty("spring.cloud.gateway.routes[0].predicates[0]", "Path=/account/**");
System.setProperty("spring.cloud.gateway.routes[0].filters[0]", "RewritePath=/account/(?<path>.*), /$\\{path}");
System.setProperty("spring.cloud.gateway.routes[0].filters[1].name", "CircuitBreaker");
System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.name", "exampleSlowCircuitBreaker");
// System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.slowCallDurationThreshold", "100");
// System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.slowCallRateThreshold", "9.0F");
// System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.fallbackUri", "forward:/fallback/account");
MockServerClient client = new MockServerClient(mockServer.getContainerIpAddress(), mockServer.getServerPort());
client.when(HttpRequest.request()
.withPath("/1"))
.respond(response()
.withBody("{\"id\":1,\"number\":\"1234567890\"}")
.withHeader("Content-Type", "application/json"));
// client.when(HttpRequest.request()
// .withPath("/2"), Times.exactly(3))
// .respond(response()
// .withBody("{\"id\":2,\"number\":\"1\"}")
// .withDelay(TimeUnit.SECONDS, 1000)
// .withHeader("Content-Type", "application/json"));
client.when(HttpRequest.request()
.withPath("/2"))
.respond(response()
.withBody("{\"id\":2,\"number\":\"1234567891\"}")
.withDelay(TimeUnit.SECONDS, 200)
.withHeader("Content-Type", "application/json"));
}
@Test
@BenchmarkOptions(warmupRounds = 0, concurrency = 1, benchmarkRounds = 600)
public void testAccountService() {
int gen = 1 + (i++ % 2);
ResponseEntity<Account> r = template.exchange("/account/{id}", HttpMethod.GET, null, Account.class, gen);
LOGGER.info("{}. Received: status->{}, payload->{}, call->{}", i, r.getStatusCodeValue(), r.getBody(), gen);
}
}
请求日志如下：当请求达到100次时候，此时失败率为50% 这时候系统开启断路器返回503！
20:07:29.281 --- [pool-2-thread-1] : 91. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:07:30.297 --- [pool-2-thread-1] : 92. Received: status->504, payload->Account(id=null, number=null), call->2
20:07:30.316 --- [pool-2-thread-1] : 93. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:07:31.328 --- [pool-2-thread-1] : 94. Received: status->504, payload->Account(id=null, number=null), call->2
20:07:31.345 --- [pool-2-thread-1] : 95. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:07:32.359 --- [pool-2-thread-1] : 96. Received: status->504, payload->Account(id=null, number=null), call->2
20:07:32.385 --- [pool-2-thread-1] : 97. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:07:33.400 --- [pool-2-thread-1] : 98. Received: status->504, payload->Account(id=null, number=null), call->2
20:07:33.414 --- [pool-2-thread-1] : 99. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:07:34.509 --- [pool-2-thread-1] : 100. Received: status->504, payload->Account(id=null, number=null), call->2
20:07:34.525 --- [pool-2-thread-1] : 101. Received: status->503, payload->Account(id=null, number=null), call->1
20:07:34.533 --- [pool-2-thread-1] : 102. Received: status->503, payload->Account(id=null, number=null), call->2
20:07:34.539 --- [pool-2-thread-1] : 103. Received: status->503, payload->Account(id=null, number=null), call->1
20:07:34.545 --- [pool-2-thread-1] : 104. Received: status->503, payload->Account(id=null, number=null), call->2
20:07:34.552 --- [pool-2-thread-1] : 105. Received: status->503, payload->Account(id=null, number=null), call->1
20:07:34.566 --- [pool-2-thread-1] : 106. Received: status->503, payload->Account(id=null, number=null), call->2
20:07:34.572 --- [pool-2-thread-1] : 107. Received: status->503, payload->Account(id=null, number=null), call->1
20:07:34.576 --- [pool-2-thread-1] : 108. Received: status->503, payload->Account(id=null, number=null), call->2
20:07:34.580 --- [pool-2-thread-1] : 109. Received: status->503, payload->Account(id=null, number=null), call->1
20:07:34.586 --- [pool-2-thread-1] : 110. Received: status->503, payload->Account(id=null, number=null), call->2
20:07:34.591 --- [pool-2-thread-1] : 111. Received: status->503, payload->Account(id=null, number=null), call->1
这时候我们修改下配置
@BeforeClass
public static void init() {
System.setProperty("logging.level.org.springframework.cloud.gateway.filter.factory", "TRACE");
System.setProperty("spring.cloud.gateway.routes[0].id", "account-service");
System.setProperty("spring.cloud.gateway.routes[0].uri", "http://localhost:" + mockServer.getServerPort());
System.setProperty("spring.cloud.gateway.routes[0].predicates[0]", "Path=/account/**");
System.setProperty("spring.cloud.gateway.routes[0].filters[0]", "RewritePath=/account/(?<path>.*), /$\\{path}");
System.setProperty("spring.cloud.gateway.routes[0].filters[1].name", "CircuitBreaker");
System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.name", "exampleSlowCircuitBreaker");
// System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.slowCallDurationThreshold", "100");
// System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.slowCallRateThreshold", "9.0F");
System.setProperty("spring.cloud.gateway.routes[0].filters[1].args.fallbackUri", "forward:/fallback/account");
MockServerClient client = new MockServerClient(mockServer.getContainerIpAddress(), mockServer.getServerPort());
client.when(HttpRequest.request()
.withPath("/1"))
.respond(response()
.withBody("{\"id\":1,\"number\":\"1234567890\"}")
.withHeader("Content-Type", "application/json"));
client.when(HttpRequest.request()
.withPath("/2"), Times.exactly(3))
.respond(response()
.withBody("{\"id\":2,\"number\":\"1\"}")
.withDelay(TimeUnit.SECONDS, 1000)
.withHeader("Content-Type", "application/json"));
client.when(HttpRequest.request()
.withPath("/2"))
.respond(response()
.withBody("{\"id\":2,\"number\":\"1234567891\"}")
// .withDelay(TimeUnit.SECONDS, 200)
.withHeader("Content-Type", "application/json"));
}
新建一个回调接口，用于断路器打开后请求的地址。
@RestController
@RequestMapping("/fallback")
public class GatewayFallback {
@GetMapping("/account")
public Account getAccount() {
Account a = new Account();
a.setId(2);
a.setNumber("123456");
return a;
}
}
使用默认设置时，前3次请求触发断路器回调，后面正常请求成功
20:20:23.529 --- [pool-2-thread-1] : 1. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:20:23.777 --- [pool-2-thread-1] : 2. Received: status->200, payload->Account(id=2, number=123456), call->2
20:20:23.808 --- [pool-2-thread-1] : 3. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:20:24.018 --- [pool-2-thread-1] : 4. Received: status->200, payload->Account(id=2, number=123456), call->2
20:20:24.052 --- [pool-2-thread-1] : 5. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:20:24.268 --- [pool-2-thread-1] : 6. Received: status->200, payload->Account(id=2, number=123456), call->2
20:20:24.301 --- [pool-2-thread-1] : 7. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:20:24.317 --- [pool-2-thread-1] : 8. Received: status->200, payload->Account(id=2, number=1234567891), call->2
20:20:24.346 --- [pool-2-thread-1] : 9. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:20:24.363 --- [pool-2-thread-1] : 10. Received: status->200, payload->Account(id=2, number=1234567891), call->2
20:20:24.378 --- [pool-2-thread-1] : 11. Received: status->200, payload->Account(id=1, number=1234567890), call->1
20:20:24.392 --- [pool-2-thread-1] : 12. Received: status->200, payload->Account(id=2, number=1234567891), call->2
20:20:24.402 --- [pool-2-thread-1] : 13. Received: status->200, payload->Account(id=1, number=1234567890), call->1
END
至此给大家介绍了Spring Cloud Gateway中断路器跟限流器使用。
欢迎关注公众号！ 公众号回复:
入群，扫码加入我们交流群！
深入学习spring cloud gateway 限流熔断的更多相关文章
- Spring Cloud Gateway限流实战
欢迎访问我的GitHub https://github.com/zq2599/blog_demos 内容:所有原创文章分类汇总及配套源码,涉及Java.Docker.Kubernetes.DevOPS ...
- Spring Cloud 微服务五：Spring cloud gateway限流
前言:在互联网应用中,特别是电商,高并发的场景非常多,比如:秒杀.抢购.双11等,在开始时间点会使流量爆发式地涌入,如果对网络流量不加控制很有可能造成后台实例资源耗尽.限流是指通过指定的策略削减流量, ...
- spring cloud gateway 限流做法
标题 随风倒十分 反对法
- Spring Cloud Zuul 限流详解（附源码）（转）
在高并发的应用中,限流往往是一个绕不开的话题.本文详细探讨在Spring Cloud中如何实现限流. 在 Zuul 上实现限流是个不错的选择,只需要编写一个过滤器就可以了,关键在于如何实现限流的算法. ...
- Spring Cloud(十二)：Spring Cloud Zuul 限流详解（附源码）（转）
前面已经介绍了很多zuul的功能,本篇继续介绍它的另一大功能.在高并发的应用中,限流往往是一个绕不开的话题.本文详细探讨在Spring Cloud中如何实现限流. 在 Zuul 上实现限流是个不错的选 ...
- spring cloud gateway 之限流篇
转载请标明出处: https://www.fangzhipeng.com 本文出自方志朋的博客 在高并发的系统中,往往需要在系统中做限流,一方面是为了防止大量的请求使服务器过载,导致服务不可用,另一方 ...
- Spring Cloud Gateway 网关限流
Spring Cloud Gateway 限流 一.背景 二.实现功能 三.网关层限流 1.使用默认的redis来限流 1.引入jar包 2.编写配置文件 3.网关正常响应 4.网关限流响应 2.自定 ...
- spring cloud gateway整合sentinel作网关限流
说明: sentinel可以作为各微服务的限流,也可以作为gateway网关的限流组件. spring cloud gateway有限流功能,但此处用sentinel来作为替待. 说明:sentine ...
- Spring Cloud Gateway服务网关
原文:https://www.cnblogs.com/ityouknow/p/10141740.html Spring 官方最终还是按捺不住推出了自己的网关组件:Spring Cloud Gatewa ...
随机推荐
- Java 优雅地退出程序
本文转载自Java 优雅地退出程序 导语 很多情况下,我们的程序需要在操作系统 后台 一直运行,这在程序代码里的实现就是用死循环 ( while (true) ) 来实现的.但是,这样会出现一个问题, ...
- 使用 Castle 实现 AOP，以及 Autofac 集成 Castle
Castle 是 2003 年诞生于 Apache Avalon 项目,目的是为了创建一个IOC 框架.发展到现在已经有四个组件: ORM组件:ActiveRecord IOC组件:Windsor 动 ...
- 使用Reactor完成类似的Flink的操作
一.背景 Flink在处理流式任务的时候有很大的优势,其中windows等操作符可以很方便的完成聚合任务,但是Flink是一套独立的服务,业务流程中如果想使用需要将数据发到kafka,用Flink处理 ...
- 基于docker创建Cassandra集群
一.概述 简介 Cassandra是一个开源分布式NoSQL数据库系统. 它最初由Facebook开发,用于储存收件箱等简单格式数据,集GoogleBigTable的数据模型与Amazon Dynam ...
- 学习java之基础语法（一）
学习java之基础语法(一) 基本语法 编写 Java 程序时,应注意以下几点: 大小写敏感:Java 是大小写敏感的,这就意味着标识符 Hello 与 hello 是不同的. 类名:对于所有的类来说 ...
- Java变量-常量-作用域
public class Demo05 { /* 变量的命名规范:见名知意 1.类变量/实例变量/局部变量使用驼峰原则命名 2.类名使用Pascal命名法 3.常量名使用大写字母和下划线 4.驼峰原则 ...
- Java 面向对象 04
面向对象·四级 多态的概述及其代码实现 * A:多态(polymorphic)概述 * 事物存在的多种形态 * B:多态前提 * a:要有继承关系 * b:要有方法重写 * c: 要有父类引用指向子类 ...
- Typora学习
Markdown学习总结 标题的使用格式 # 一阶标题 或者 ctrl + 1 ## 二阶标题 或者 ctrl + 2 ### 三阶标题 或者 ctrl + 3 #### 四阶标题 或者 ctrl + ...
- fastjson<=1.2.47反序列化漏洞复现
0x00:前言 这个漏洞爆出来之后本来一直打算挑时间去复现,后来一个朋友突然发来他们站点存在fastjson这个漏洞被白帽子发了报告.既然漏洞环境送上门来,我便打算直接下手试一试.在我的想象中当然是一 ...
- WS1008网络损伤测试仪
WS1008网络损伤测试仪具备高性能的网络损伤仿真功能.冗余链路测试功能和线速流量生成功能,提供了综合性的网络系统测试方案,可充分测试.验证网络系统的抗损伤能力.链路切换能力及数据转发能力.为高可靠性 ...