spring cloud gateway 自定义负载均衡

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spring cloud gateway 自定义负载均衡

 

 

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相关类及接口

 

LoadbalancerClientFilter：使用ribbon负载均衡，默认使用该类（已不推荐使用）

/** @deprecated */
@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.loadbala