com.alibaba.csp.sentinel.adapter.spring.webmvc.callback.DefaultBlockExceptionHandler Maven / Gradle / Ivy
/*
* Copyright 1999-2019 Alibaba Group Holding Ltd.
*
* 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 com.alibaba.csp.sentinel.adapter.spring.webmvc.callback;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import com.alibaba.csp.sentinel.util.StringUtil;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.PrintWriter;
/**
* Default handler for the blocked request.
*
* @author kaizi2009
*/
public class DefaultBlockExceptionHandler implements BlockExceptionHandler {
@Override
public void handle(HttpServletRequest request, HttpServletResponse response, BlockException e) throws Exception {
// Return 429 (Too Many Requests) by default.
response.setStatus(429);
StringBuffer url = request.getRequestURL();
if ("GET".equals(request.getMethod()) && StringUtil.isNotBlank(request.getQueryString())) {
url.append("?").append(request.getQueryString());
}
PrintWriter out = response.getWriter();
out.print("Blocked by Sentinel (flow limiting)");
out.flush();
out.close();
}
}