Solon Cloud Gateway 开发：Route 的过滤器与定制

RouteFilterFactory 是专为路由过滤拦截处理设计的接口。对应路由配置 filters

1、内置的路由过滤器

过滤器工厂	本置前缀	说明与示例
AddRequestHeaderFilterFactory	AddRequestHeader=	添加请求头 (AddRequestHeader=Demo-Ver,1.0)
AddResponseHeaderFilterFactory	AddResponseHeader=	添加响应头 (AddResponseHeader=Demo-Ver,1.0)
PrefixPathFilterFactory	PrefixPath=	附加路径前缀 (PrefixPath=/app)
RedirectToFilterFactory	RedirectTo=	跳转到 (RedirectTo=302,http://demo.org/a,true)
RemoveRequestHeaderFilterFactory	RemoveRequestHeader=	移除请求头 (RemoveRequestHeader=Demo-Ver,1.0)
RemoveResponseHeaderFilterFactory	RemoveResponseHeader=	移除响应头 (RemoveResponseHeader=Demo-Ver,1.0)
StripPrefixFilterFactory	StripPrefix=	移除路径前缀段数 (StripPrefix=1)

2、定制示例

• StripPrefix 过滤器定制示例（配置例：StripPrefix=1）

@Component
public class StripPrefixFilterFactory implements RouteFilterFactory {

    @Override
    public String prefix() {
        return "StripPrefix";
    }

    @Override
    public ExFilter create(String config) {
        return new StripPrefixFilter(config);
    }

    public static class StripPrefixFilter implements ExFilter {
        private int parts;

        public StripPrefixFilter(String config) {
            if (Utils.isBlank(config)) {
                throw new IllegalArgumentException("StripPrefixFilter config cannot be blank");
            }

            this.parts = Integer.parseInt(config);
        }

        @Override
        public Completable doFilter(ExContext ctx, ExFilterChain chain) {
            //目标路径重组
            List<String> pathFragments = Arrays.asList(ctx.newRequest().getPath().split("/", -1));
            String newPath = "/" + String.join("/", pathFragments.subList(parts + 1, pathFragments.size()));
            ctx.newRequest().path(newPath);

            return chain.doFilter(ctx);
        }
    }
}