RestCorsFilter.java

/**
 *  Copyright 2005-2016 Red Hat, Inc.
 *
 *  Red Hat 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 io.fabric8.rest.utils;

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.HttpServletResponse;
import java.io.IOException;

/**
 * A simple CORS filter that can used to allow the swagger ui or other API browsers from remote origins to access the
 * Rest services exposes by this Camel swagger module.
 */
public class RestCorsFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    @Override
    public void destroy() {
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        if (response instanceof HttpServletResponse) {
            HttpServletResponse httpResponse = (HttpServletResponse) response;
            httpResponse.setHeader("Access-Control-Allow-Origin", "*");
            httpResponse.setHeader("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, DELETE, TRACE, OPTIONS, CONNECT, PATCH");
            httpResponse.setHeader("Access-Control-Max-Age", "3600");
            httpResponse.setHeader("Access-Control-Allow-Headers", "Origin, Accept, X-Requested-With, Content-Type, Access-Control-Request-Method, Access-Control-Request-Headers");
        }
        chain.doFilter(request, response);
    }
}