/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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
*
* http://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 org.apache.ambari.server.api;
import org.springframework.http.HttpMethod;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
public class MethodOverrideFilter implements Filter {
private static final String HEADER_NAME = "X-Http-Method-Override";
//limit override to GET method only (no need for others now)
private static final List<String> ALLOWED_METHODS = new ArrayList<String>(){{
add("GET");
}};
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
if (request instanceof HttpServletRequest) {
HttpServletRequest httpServletRequest = (HttpServletRequest) request;
String method = httpServletRequest.getHeader(HEADER_NAME);
if (method != null) {
if (ALLOWED_METHODS.contains(method.toUpperCase())) {
final HttpMethod httpMethod = HttpMethod.valueOf(method.toUpperCase());
HttpServletRequestWrapper requestWrapper = new HttpServletRequestWrapper(httpServletRequest){
@Override
public String getMethod() {
return httpMethod.toString();
}
};
chain.doFilter(requestWrapper, response);
return;
} else {
HttpServletResponse httpResponse = (HttpServletResponse) response;
httpResponse.sendError(400, "Incorrect HTTP method for override: "+ method + ". Allowed values: "+ ALLOWED_METHODS);
}
}
}
chain.doFilter(request, response);
}
@Override
public void destroy() {
}
}