org.springframework.boot.web.servlet.filter.ApplicationContextHeaderFilter Maven / Gradle / Ivy
/*
* Copyright 2012-2018 the original author or authors.
*
* 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 org.springframework.boot.web.servlet.filter;
import java.io.IOException;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.context.ApplicationContext;
import org.springframework.web.filter.OncePerRequestFilter;
/**
* {@link OncePerRequestFilter} to add an {@literal X-Application-Context} header that
* contains the {@link ApplicationContext#getId() ApplicationContext ID}.
*
* @author Phillip Webb
* @author Venil Noronha
* @since 2.0.0
*/
public class ApplicationContextHeaderFilter extends OncePerRequestFilter {
/**
* Public constant for {@literal X-Application-Context}.
*/
public static final String HEADER_NAME = "X-Application-Context";
private final ApplicationContext applicationContext;
public ApplicationContextHeaderFilter(ApplicationContext context) {
this.applicationContext = context;
}
@Override
protected void doFilterInternal(HttpServletRequest request,
HttpServletResponse response, FilterChain filterChain)
throws ServletException, IOException {
response.addHeader(HEADER_NAME, this.applicationContext.getId());
filterChain.doFilter(request, response);
}
}