springcloud gateway如何实现路由和负载均衡-编程学习网

简介：

gateway主要是做路由负载，过滤主要是替代zuul 1.x 性能比zuul好 zuul是基于

Servlet ，gateway是基于spring-webflux 用的netty+reactor

yml文件

实现路由负载的配置亲自测试


spring:
  application:
    name: xgyx_gateway
  cloud:
    discovery:
      locator:
        enabled: true
    gateway:
       routes:
       - id: a  #随便定义不重复就好
         uri: lb://xgyx-welfareservice-x  #服务名称
         predicates:
         - Path=/m
@Deprecated
public class LoadBalancerClientFilter implements GlobalFilter, Ordered {
    public static final int LOAD_BALANCER_CLIENT_FILTER_ORDER = 10100;
    private static final Log log = LogFactory.getLog(LoadBalancerClientFilter.class);
    protected final LoadBalancerClient loadBalancer;
    private LoadBalancerProperties properties;
 
    public LoadBalancerClientFilter(LoadBalancerClient loadBalancer, LoadBalancerProperties properties) {
        this.loadBalancer = loadBalancer;
        this.properties = properties;
    }
 
    public int getOrder() {
        return 10100;
    }
 
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        URI url = (URI)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
        String schemePrefix = (String)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_SCHEME_PREFIX_ATTR);
        if (url != null && ("lb".equals(url.getScheme()) || "lb".equals(schemePrefix))) {
            ServerWebExchangeUtils.addOriginalRequestUrl(exchange, url);
            if (log.isTraceEnabled()) {
                log.trace("LoadBalancerClientFilter url before: " + url);
            }
 
            ServiceInstance instance = this.choose(exchange);
            if (instance == null) {
                throw NotFoundException.create(this.properties.isUse404(), "Unable to find instance for " + url.getHost());
            } else {
                URI uri = exchange.getRequest().getURI();
                String overrideScheme = instance.isSecure() ? "https" : "http";
                if (schemePrefix != null) {
                    overrideScheme = url.getScheme();
                }
 
                URI requestUrl = this.loadBalancer.reconstructURI(new DelegatingServiceInstance(instance, overrideScheme), uri);
                if (log.isTraceEnabled()) {
                    log.trace("LoadBalancerClientFilter url chosen: " + requestUrl);
                }
 
                exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, requestUrl);
                return chain.filter(exchange);
            }
        } else {
            return chain.filter(exchange);
        }
    }
 
    protected ServiceInstance choose(ServerWebExchange exchange) {
        return this.loadBalancer.choose(((URI)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR)).getHost());
    }
}

说明：默认使用该类，可通过下述方法使用ReactiveLoadbalancerClientFilter

"You already have RibbonLoadBalancerClient on your classpath. It will be used by default.
As Spring Cloud Ribbon is in maintenance mode. We recommend switching to " + BlockingLoadBalancerClient.class.getSimpleName() + " instead.
In order to use it, set the value of `spring.cloud.loadbalancer.ribbon.enabled` to `false`
or remove spring-cloud-starter-netflix-ribbon from your project."

ReactiveLoadBalancerClientFilter：负载均衡拦截器


public class ReactiveLoadBalancerClientFilter implements GlobalFilter, Ordered {
    private static final Log log = LogFactory.getLog(ReactiveLoadBalancerClientFilter.class);
    private static final int LOAD_BALANCER_CLIENT_FILTER_ORDER = 10150;
    private final LoadBalancerClientFactory clientFactory;
    private LoadBalancerProperties properties; 
    public ReactiveLoadBalancerClientFilter(LoadBalancerClientFactory clientFactory, LoadBalancerProperties properties) {
        this.clientFactory = clientFactory;
        this.properties = properties;
    }
 
    public int getOrder() {
        return 10150;
    }
 
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        URI url = (URI)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
        String schemePrefix = (String)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_SCHEME_PREFIX_ATTR);
        if (url != null && ("lb".equals(url.getScheme()) || "lb".equals(schemePrefix))) {
                            //url不为null且协议为lb，或者url以lb开头
 
            ServerWebExchangeUtils.addOriginalRequestUrl(exchange, url);
            if (log.isTraceEnabled()) {
                log.trace(ReactiveLoadBalancerClientFilter.class.getSimpleName() + " url before: " + url);
            }
 
            return this.choose(exchange).doOnNext((response) -> {
                            //获取ServiceInstance实例，进行一些处理
 
                if (!response.hasServer()) {
                            //如果没有serviceInstance，直接抛出异常
 
                    throw NotFoundException.create(this.properties.isUse404(), "Unable to find instance for " + url.getHost());
                } else {    //如果有serviceInstance，进行相关处理
                    URI uri = exchange.getRequest().getURI();
                    String overrideScheme = null;
                    if (schemePrefix != null) {
                        overrideScheme = url.getScheme();
                    }
 
                    DelegatingServiceInstance serviceInstance = new DelegatingServiceInstance((ServiceInstance)response.getServer(), overrideScheme);
                    URI requestUrl = LoadBalancerUriTools.reconstructURI(serviceInstance, uri);
                    if (log.isTraceEnabled()) {
                        log.trace("LoadBalancerClientFilter url chosen: " + requestUrl);
                    }
 
                    exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, requestUrl);
                }
            }).then(chain.filter(exchange));
        } else {
            return chain.filter(exchange); //如果获取不到serviceInstance，直接进行后续过滤
        }
    }
 
    private Mono<Response<ServiceInstance>> choose(ServerWebExchange exchange) {
        URI uri = (URI)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
        ReactorLoadBalancer<ServiceInstance> loadBalancer = (ReactorLoadBalancer)this.clientFactory.getInstance(uri.getHost(), ReactorLoadBalancer.class, new Class[]{ServiceInstance.class});
        if (loadBalancer == null) {
            throw new NotFoundException("No loadbalancer available for " + uri.getHost());
        } else {
            return loadBalancer.choose(this.createRequest());
        }
    }//选择服务实例
 
    private Request createRequest() {
        return ReactiveLoadBalancer.REQUEST;
    }
}

ReactorLoadBalancer：负载均衡接口


public interface ReactorLoadBalancer<T> extends ReactiveLoadBalancer<T> {
    Mono<Response<T>> choose(Request request); 
    default Mono<Response<T>> choose() {
        return this.choose(REQUEST);
    }
} 
*********************** 
public interface ReactorServiceInstanceLoadBalancer extends ReactorLoadBalancer<ServiceInstance> {
}

RoundRobinLoadbalancer：负载均衡使用轮询


public class RoundRobinLoadBalancer implements ReactorServiceInstanceLoadBalancer {
    private static final Log log = LogFactory.getLog(RoundRobinLoadBalancer.class);
    private final AtomicInteger position; 
    private ObjectProvider<ServiceInstanceListSupplier> serviceInstanceListSupplierProvider;
    private final String serviceId;
 
************
构造方法
 
    public RoundRobinLoadBalancer(ObjectProvider<ServiceInstanceListSupplier> serviceInstanceListSupplierProvider, String serviceId) {
    public RoundRobinLoadBalancer(ObjectProvider<ServiceInstanceListSupplier> serviceInstanceListSupplierProvider, String serviceId, int seedPosition) {
 
************
普通方法
 
    public Mono<Response<ServiceInstance>> choose(Request request) {
        if (this.serviceInstanceListSupplierProvider != null) {
            ServiceInstanceListSupplier supplier = (ServiceInstanceListSupplier)this.serviceInstanceListSupplierProvider.getIfAvailable(NoopServiceInstanceListSupplier::new);
            return ((Flux)supplier.get()).next().map(this::getInstanceResponse);
        } else {
            ServiceInstanceSupplier supplier = (ServiceInstanceSupplier)this.serviceInstanceSupplier.getIfAvailable(NoopServiceInstanceSupplier::new);
            return ((Flux)supplier.get()).collectList().map(this::getInstanceResponse);
        }
    }
 
    private Response<ServiceInstance> getInstanceResponse(List<ServiceInstance> instances) {
        if (instances.isEmpty()) {
            log.warn("No servers available for service: " + this.serviceId);
            return new EmptyResponse();
        } else {
            int pos = Math.abs(this.position.incrementAndGet());
            ServiceInstance instance = (ServiceInstance)instances.get(pos % instances.size());
            return new DefaultResponse(instance);
        }
    }//使用轮询获取实例
}

示例：

参数id为偶数时，输出hello new version

网关

配置文件


spring:
  application:
    name: hello-gateway
  cloud:
    consul:
      host: 172.18.0.20
      port: 8500
    loadbalancer:
      ribbon:
        enabled: false
    gateway:
      routes:
        - id: myRoute
          uri: lb://hello-service
          predicates:
            - Path=/hello

自定义过滤器


@Component
public class CustomLoadBalancerClientFilter implements GlobalFilter, Ordered {
    private static final Log log = LogFactory.getLog(org.springframework.cloud.gateway.filter.ReactiveLoadBalancerClientFilter.class);
 
    @Resource
    private final LoadBalancerClientFactory clientFactory;
 
    @Resource
    private LoadBalancerProperties properties;
 
    public CustomLoadBalancerClientFilter(LoadBalancerClientFactory clientFactory, LoadBalancerProperties properties) {
        this.clientFactory = clientFactory;
        this.properties = properties;
    }
 
    public int getOrder() {
        return 10149;
    }
 
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        URI url = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
        String schemePrefix = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_SCHEME_PREFIX_ATTR);
        if (url != null && ("lb".equals(url.getScheme()) || "lb".equals(schemePrefix))) {
            ServerWebExchangeUtils.addOriginalRequestUrl(exchange, url);
            if (log.isTraceEnabled()) {
                log.trace(ReactiveLoadBalancerClientFilter.class.getSimpleName() + " url before: " + url);
            }
 
            return this.choose(exchange).doOnNext((response) -> {
                if (!response.hasServer()) {
                    throw NotFoundException.create(this.properties.isUse404(), "Unable to find instance for " + url.getHost());
                } else {
                    URI uri = exchange.getRequest().getURI();
                    String overrideScheme = null;
                    if (schemePrefix != null) {
                        overrideScheme = url.getScheme();
                    }
 
                    int id=Integer.parseInt(Objects.requireNonNull(exchange.getRequest().getQueryParams().getFirst("id")));
                    if (id%2==0){
                        while (!"new".equals(response.getServer().getMetadata().get("version"))){
                            try {
                                response=this.choose(exchange).toFuture().get();
                            }catch (Exception e){
                                System.out.println(e.getMessage());
                            }
                        }
                    }
 
                    DelegatingServiceInstance serviceInstance = new DelegatingServiceInstance(response.getServer(), overrideScheme);
 
                    System.out.println(exchange.getRequest().getQueryParams().getFirst("id")+"对应server的version为："+serviceInstance.getMetadata().get("version"));
                    URI requestUrl = LoadBalancerUriTools.reconstructURI(serviceInstance, uri);
                    if (log.isTraceEnabled()) {
                        log.trace("LoadBalancerClientFilter url chosen: " + requestUrl);
                    }
 
                    exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, requestUrl);
                }
            }).then(chain.filter(exchange));
        } else {
            return chain.filter(exchange);
        }
    }
 
    private Mono<Response<ServiceInstance>> choose(ServerWebExchange exchange) {
        URI uri = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
        assert uri != null;
        ReactorLoadBalancer<ServiceInstance> loadBalancer = this.clientFactory.getInstance(uri.getHost(), ReactorLoadBalancer.class, new Class[]{ServiceInstance.class});
        if (loadBalancer == null) {
            throw new NotFoundException("No loadbalancer available for " + uri.getHost());
        } else {
            return loadBalancer.choose(this.createRequest());
        }
    }
 
    private Request createRequest() {
        return ReactiveLoadBalancer.REQUEST;
    }
}

同名应用hello-service1

配置文件


spring:
  application:
    name: hello-service
  cloud:
    consul:
      host: 172.18.0.20
      port: 8500
      discovery:
        instance-id: ${spring.application.name}-${random.int}
        tags: version=old

controller 层


@RestController
public class HelloController { 
    @RequestMapping("/hello")
    public String hello(){
        return "hello old version";
    }
}

同名应用hello-service2

配置文件


spring:
  application:
    name: hello-service
  cloud:
    consul:
      host: 172.18.0.20
      port: 8500
      discovery:
        instance-id: ${spring.application.name}-${random.int}
        tags: version=new

controller 层


@RestController
public class HelloController { 
    @RequestMapping("/hello")
    public String hello(){
        return "hello new version";
    }
}

测试输出

consul注册的应用

参数测试

当id为偶数时，输出为hello new version

以上为个人经验，希望能给大家一个参考，也希望大家多多支持编程网。

文章详情

springcloud gateway如何实现路由和负载均衡

简介：

yml文件

示例：

测试输出

软考中级精品资料免费领

相关文章

猜你喜欢

springcloud gateway如何实现路由和负载均衡

springcloud gateway怎么实现路由和负载均衡

基于Spring Cloud Gateway，实现路由和负载均衡

静态路由如何实现负载均衡

SpringCloud如何实现Zuul集群(负载均衡)

SpringCloud Gateway详细分析实现负载均衡与熔断和限流

springcloud负载均衡怎么实现

springcloud怎么实现负载均衡

SpringCloud中如何利用Ribbon实现负载均衡

SpringCloud怎么实现Ribbon负载均衡

springcloud负载均衡策略怎么实现

负载均衡如何实现

redis如何实现负载均衡

SpringCloud Zuul实现负载均衡和熔断机制方式

nginx如何实现负载均衡

nacos负载均衡如何实现

ngnix如何实现负载均衡

SpringCloud Zuul怎么实现负载均衡和熔断机制

如何利用负载均衡器实现终极自由

Tomcat中如何实现负载均衡