源码分析-SpringCloudGateway源码阅读-网关自定义事件

源码解析-SpringCloudGateway
01 源码分析-SpringCloudGateway源码阅读准备
02 源码分析-SpringCloudGateway源码阅读-网关监控端点
03 源码分析-SpringCloudGateway源码阅读-网关配置类
04 源码分析-SpringCloudGateway源码阅读-服务发现
05 源码分析-SpringCloudGateway源码阅读-网关自定义事件
06 源码分析-SpringCloudGateway源码阅读-过滤器包类总览
07 源码分析-SpringCloudGateway源码阅读-过滤器-全局过滤器源码(一)
08 源码分析-SpringCloudGateway源码阅读-过滤器-全局过滤器源码(二)
09 源码分析-SpringCloudGateway源码阅读-过滤器-全局过滤器源码(三)
10 源码分析-SpringCloudGateway源码阅读-过滤器-路由过滤器源码解读
11 源码分析-SpringCloudGateway源码阅读-处理器源码

一 网关自定义事件相关类

主要有六个事件类及其说明如下：

.
└── org
    └── springframework
        └── cloud
            └── gateway
                └── event
                    ├── EnableBodyCachingEvent.java 缓存请求body的事件
                    ├── FilterArgsEvent.java 过滤器参数事件
                    ├── PredicateArgsEvent.java 路由谓词参数事件
                    ├── RefreshRoutesEvent.java 刷新路由事件
                    ├── RefreshRoutesResultEvent.java 路由刷新结果事件
                    └── WeightDefinedEvent.java  权重定义事件

二 每个类的具体说明

EnableBodyCachingEvent

/*
 * Copyright 2013-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.gateway.event;

import org.springframework.context.ApplicationEvent;

/**
 * 缓存请求body的事件
 *
 * 当使用RetryGatewayFilterFactory路由过滤器时，会在该过滤器发送一个缓存请求body的事件
 * 然后在全局过滤器AdaptCachedBodyGlobalFilter中会监听该事件，监听到之后会把该路由的请求body缓存起来，便于后面重试使用
 */
public class EnableBodyCachingEvent extends ApplicationEvent {

	private final String routeId;

	public EnableBodyCachingEvent(Object source, String routeId) {
		super(source);
		this.routeId = routeId;
	}

	public String getRouteId() {
		return this.routeId;
	}

}

FilterArgsEvent

/*
 * Copyright 2013-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.gateway.event;

import java.util.Map;

import org.springframework.context.ApplicationEvent;

/**
 * 过滤器参数事件
 * 由路由定义定位器RouteDefinitionRouteLocator中加载路由过滤器的时候发送事件（主要是限流相关的）
 * 在限流抽象类AbstractRateLimiter中监听事件并处理事件（非限流相关参数不处理直接返回）
 */
public class FilterArgsEvent extends ApplicationEvent {

	private final Map<String, Object> args;

	private String routeId;

	public FilterArgsEvent(Object source, String routeId, Map<String, Object> args) {
		super(source);
		this.routeId = routeId;
		this.args = args;
	}

	public String getRouteId() {
		return routeId;
	}

	public Map<String, Object> getArgs() {
		return args;
	}

}

PredicateArgsEvent

/*
 * Copyright 2013-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.gateway.event;

import java.util.Map;

import org.springframework.context.ApplicationEvent;

/**
 * 路由谓词参数事件
 *
 * 由路由定义定位器RouteDefinitionRouteLocator中转换路由谓词的时候发送事件（主要是权重相关的）
 * 在权重计算web过滤器WeightCalculatorWebFilter中监听事件并处理事件（非权重相关参数不处理直接返回）
 *
 */
public class PredicateArgsEvent extends ApplicationEvent {

	private final Map<String, Object> args;

	private String routeId;

	public PredicateArgsEvent(Object source, String routeId, Map<String, Object> args) {
		super(source);
		this.routeId = routeId;
		this.args = args;
	}

	public String getRouteId() {
		return routeId;
	}

	public Map<String, Object> getArgs() {
		return args;
	}

}

RefreshRoutesEvent

/*
 * Copyright 2013-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.gateway.event;

import org.springframework.context.ApplicationEvent;

/**
 * 刷新路由事件
 *
 * 可由网关端点AbstractGatewayControllerEndpoint刷新接口端点 触发
 * 或者由RouteRefreshListener重置时触发
 *
 * 缓存路由定位CachingRouteLocator中订阅事件并处理刷新缓存
 *
 *
 * @author Spencer Gibb
 */
public class RefreshRoutesEvent extends ApplicationEvent {

	/**
	 * Create a new ApplicationEvent.
	 * @param source the object on which the event initially occurred (never {@code null})
	 */
	public RefreshRoutesEvent(Object source) {
		super(source);
	}

}

RefreshRoutesResultEvent

/*
 * Copyright 2013-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.gateway.event;

import org.springframework.context.ApplicationEvent;

/**
 * 路由刷新结果事件
 * 由缓存路由定位CachingRouteLocator处理刷新路由事件时触发的结果事件
 *
 * @author alvin
 */
public class RefreshRoutesResultEvent extends ApplicationEvent {

	private Throwable throwable;

	public RefreshRoutesResultEvent(Object source, Throwable throwable) {
		super(source);
		this.throwable = throwable;
	}

	public RefreshRoutesResultEvent(Object source) {
		super(source);
	}

	public Throwable getThrowable() {
		return throwable;
	}

	public boolean isSuccess() {
		return throwable == null;
	}

}

WeightDefinedEvent

/*
 * Copyright 2013-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.gateway.event;

import org.springframework.cloud.gateway.support.WeightConfig;
import org.springframework.context.ApplicationEvent;

/**
 * 权重定义事件
 * 由权重路由谓词工厂WeightRoutePredicateFactory触发发送事件
 * 由权重计算Web过滤器 WeightCalculatorWebFilter 订阅处理
 */
public class WeightDefinedEvent extends ApplicationEvent {

	private final WeightConfig weightConfig;

	public WeightDefinedEvent(Object source, WeightConfig weightConfig) {
		super(source);
		this.weightConfig = weightConfig;
	}

	public WeightConfig getWeightConfig() {
		return weightConfig;
	}

}