之前在用zuul网关的时候，请求几次然后连接就断开了。原因是因为http1.1之后，默认走的都是connection=keep-alive 长连接。但没有心跳维持，顾1分钟断开一次。但RestFul一般都是走短连接就行了。因此想着只要修改头部connection属性就行了.
就是在过滤器中修改Zuul的RequestContext ctx对象
//设置请求为短连接
ctx.addZuulRequestHeader("connection", "close");再次请求之后发现
纳尼，怎么还是长连接。那么说明可能是我的设置没有生效或者被覆盖掉了。遇到问题，除了度娘，跟着源码走一遭也是最好的方式。花了大半天时间，终于让我找到原因了。
原因是代理类ProxyRequestHelper里面有段逻辑。
public boolean isIncludedHeader(String headerName) {
String name = headerName.toLowerCase();
RequestContext ctx = RequestContext.getCurrentContext();
if (ctx.containsKey(IGNORED_HEADERS)) {
Object object = ctx.get(IGNORED_HEADERS);
if (object instanceof Collection && ((Collection<?>) object).contains(name)) {
return false;
}
}
switch (name) {
case "host":
if(addHostHeader) {
return true;
}
case "connection":
case "content-length":
case "server":
case "transfer-encoding":
case "x-application-context":
return false;
default:
return true;
}
}如果头部存在"connection": "content-length": "server": "transfer-encoding": "x-application-context"这些头的话都被跳过。不会被设置成功。应该是zuul自己的一个机制把。
那么问题找到了，该怎么修改呢？那么只能自定义路由了。继承并重写这个类。
1、实现自定义路由配置CustomZuulConfig
@Component
public class CustomZuulConfig {
@Autowired
ZuulProperties zuulProperties;
@Value("${servletPath}")
private String servletPath;
@Bean
public CustomRouteLocator routeLocator() {
CustomRouteLocator routeLocator = new CustomRouteLocator(servletPath, this.zuulProperties);
return routeLocator;
}
}2、实现自定义请求代理工具类 重写isIncludedHeader方法。
public class CustomRequestHelper extends ProxyRequestHelper {
@Override
public boolean isIncludedHeader(String headerName) {
String name = headerName.toLowerCase();
RequestContext ctx = RequestContext.getCurrentContext();
if (ctx.containsKey(IGNORED_HEADERS)) {
Object object = ctx.get(IGNORED_HEADERS);
if (object instanceof Collection && ((Collection<?>)object).contains(name)) {
return false;
}
}
switch (name) {
case "content-length":
case "host":
case "server":
case "transfer-encoding":
case "x-application-context":
return false;
default:
return true;
}
}
} 3、重写实现代理配置类
@Configuration
@EnableZuulProxy
public class CustomZuulProxyConfig extends ZuulProxyAutoConfiguration {
@Bean
@Override
public SimpleHostRoutingFilter simpleHostRoutingFilter(ProxyRequestHelper helper, ZuulProperties zuulProperties,
ApacheHttpClientConnectionManagerFactory connectionManagerFactory,
ApacheHttpClientFactory httpClientFactory) {
CustomRequestHelper customRequestHelper = new CustomRequestHelper();
return new SimpleHostRoutingFilter(customRequestHelper, zuulProperties, connectionManagerFactory,
httpClientFactory);
}
}然后重新启动，查看请求头。
修改成功。所以说，学会通过看源码查问题，还是很重要的哈~
