spring cloud gateway获取请求的真实地址
在使用spring cloud gateway的时候，路由一般配置为服务名
例如 lb://BASE-API-WEB/xxx/bbb 路径，我们无从知道，他真正路由到什么地方去了。
经过查看源码我发现了，
org.springframework.cloud.gateway.filter.LoadBalancerClientFilter这个filter中 对lb请求进行了处理，转换成真正的url地址。
核心方法如下
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
//lb下的url
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)) {
return chain.filter(exchange);
} else {
ServerWebExchangeUtils.addOriginalRequestUrl(exchange, url);
log.trace("LoadBalancerClientFilter url before: " + url);
ServiceInstance instance = this.loadBalancer.choose(url.getHost());
if (instance == null) {
throw new NotFoundException("Unable to find instance for " + url.getHost());
} else {
URI uri = exchange.getRequest().getURI();
String overrideScheme = null;
if (schemePrefix != null) {
overrideScheme = url.getScheme();
}
//真实的url
URI requestUrl = this.loadBalancer.reconstructURI(new LoadBalancerClientFilter.DelegatingServiceInstance(instance, overrideScheme), uri);
log.trace("LoadBalancerClientFilter url chosen: " + requestUrl);
exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, requestUrl);
return chain.filter(exchange);
}
}
}其实，spring cloud gateway 已经打印了日志，但是默认的他是trace级别的，我们常用的日志级别是info级别，所有他不会打印，这就导致了我们在日志中看不到真实的url地址
以下是解决办法
1.在配置文件中设置org.springframework.cloud.gateway.filter.LoadBalancerClientFilter的日志级别
logging.level.org.springframework.cloud.gateway.filter.LoadBalancerClientFilter=TRACE注意 这里的配置一定要在
logging.level.org.springframework之后配置 不然会覆盖2.重写LoadBalancerClientFilter 建立org.springframework.cloud.gateway.filter包 将 类重写 spingboot默认会从本项目中加载类，原先的类就被弃用了。
3.继承LoadBalancerClientFilter 重写filter方法，将日志级别改为info即可
@Override
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)) {
return chain.filter(exchange);
} else {
ServerWebExchangeUtils.addOriginalRequestUrl(exchange, url);
ServiceInstance instance = this.loadBalancer.choose(url.getHost());
if (instance == null) {
throw new NotFoundException("Unable to find instance for " + url.getHost());
} else {
URI uri = exchange.getRequest().getURI();
String overrideScheme = null;
if (schemePrefix != null) {
overrideScheme = url.getScheme();
}
URI requestUrl = this.loadBalancer.reconstructURI(new LoadBalancerClientFilterBean.DelegatingServiceInstance(instance, overrideScheme), uri);
logger.info("before url = {} , url chosen = {} " ,url, requestUrl);
exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, requestUrl);
return chain.filter(exchange);
}
}
}最终效果如下 ：
spring cloud的GateWay网关中如何debug得到真实的路由地址
org.springframework.cloud.gateway.filter下面的
然后按下 Step over 就得到了 mergedUrl 这个变量，然后就可以看到真实请求的地址了
总结
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。
