通过zuul网关处理requestURI可以做很多事情，如对uri的解密，转发，大小写转化等。
这里对URI做一个简单的大小写的转化。
写一个filter实现ZuulFilter:
package com.cis.mr.audit.config; import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException; import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper; import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.PRE_TYPE; /**
* @author ：hkk
* @date ：Created in 2019/7/11 9:45
*/ public class CaseInsenistiveFilter extends ZuulFilter {
@Override
public String filterType() {
return PRE_TYPE;
} @Override
public int filterOrder() {
return 4;
} @Override
public boolean shouldFilter() {
return true;
} @Override
public Object run() throws ZuulException {
RequestContext ctx = RequestContext.getCurrentContext();
HttpServletRequest request = ctx.getRequest();
String requestURI = request.getRequestURI(); HttpServletRequestWrapper requestWrapper = new HttpServletRequestWrapper(request){
@Override
public String getRequestURI() {
return requestURI.toLowerCase();
}
}; ctx.setRequest(requestWrapper); return null;
}
}
注意这里有几点：
1. filterType是PRE_TYPE ，这是zuul定义的常量。可以通过FilterConstants查看。PRE_TYPE如下图，表示在处理转发请求之前的操作。
2. flterOrder是4,为什么是4,这里要了解zuul几个自带的filter。特别是PreDecorationFilter
下面是几个常用filter的order:
/**
* Filter Order for {@link DebugFilter#filterOrder()}.
*/
public static final int DEBUG_FILTER_ORDER = 1; /**
* Filter Order for
* {@link org.springframework.cloud.netflix.zuul.filters.pre.FormBodyWrapperFilter#filterOrder()}.
*/
public static final int FORM_BODY_WRAPPER_FILTER_ORDER = -1; /**
* Filter Order for
* {@link org.springframework.cloud.netflix.zuul.filters.pre.PreDecorationFilter}.
*/
public static final int PRE_DECORATION_FILTER_ORDER = 5; /**
* Filter Order for
* {@link org.springframework.cloud.netflix.zuul.filters.route.RibbonRoutingFilter#filterOrder()}.
*/
public static final int RIBBON_ROUTING_FILTER_ORDER = 10; /**
* Filter Order for
* {@link org.springframework.cloud.netflix.zuul.filters.post.SendErrorFilter#filterOrder()}.
*/
public static final int SEND_ERROR_FILTER_ORDER = 0; /**
* Filter Order for {@link SendForwardFilter#filterOrder()}.
*/
public static final int SEND_FORWARD_FILTER_ORDER = 500; /**
* Filter Order for
* {@link org.springframework.cloud.netflix.zuul.filters.post.SendResponseFilter#filterOrder()}.
*/
public static final int SEND_RESPONSE_FILTER_ORDER = 1000; /**
* Filter Order for
* {@link org.springframework.cloud.netflix.zuul.filters.route.SimpleHostRoutingFilter#filterOrder()}.
*/
public static final int SIMPLE_HOST_ROUTING_FILTER_ORDER = 100; /**
* filter order for {@link Servlet30WrapperFilter#filterOrder()}.
*/
public static final int SERVLET_30_WRAPPER_FILTER_ORDER = -2; /**
* filter order for
* {@link org.springframework.cloud.netflix.zuul.filters.pre.ServletDetectionFilter#filterOrder()}.
*/
public static final int SERVLET_DETECTION_FILTER_ORDER = -3;
可以看到PreDecorationFilter的order是5,在它之前的filter，我们设置一个getRequestURI的值，就可以实现需求，PreDecorationFilter是zuul很重要的过滤器，推荐大家仔细了解一下。
最后，我们注入这上fitler。
@Bean
public CaseInsenistiveFilter getCaseFilter() {
return new CaseInsenistiveFilter();
}