webapp/fmprod/src/main/java/org/apache/oodt/cas/product/jaxrs/filters/CORSFilter.java

/*
 * 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.oodt.cas.product.jaxrs.filters;

import java.io.IOException;
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.HttpServletResponse;
import javax.ws.rs.ext.Provider;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * CORS Filter class for Proposing Apache OODT-2.0 FileManager REST-APIs This is the CORS
 * (Cross-origin Resource Sharing) Filter class for FMProd REST APIs
 *
 * @author ngimhana (Nadeeshan Gimhana)
 */
@Provider
public class CORSFilter implements Filter {

  private static Logger logger = LoggerFactory.getLogger(CORSFilter.class);

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

  /**
   * @param servletRequest
   * @param servletResponse
   * @param filterChain
   * @throws IOException
   * @throws ServletException
   */
  @Override
  public void doFilter(
      ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
      throws IOException, ServletException {
    HttpServletRequest request = (HttpServletRequest) servletRequest;
    logger.debug("CORSFilter HTTP Request: {}", request.getMethod());

    HttpServletResponse resp = (HttpServletResponse) servletResponse;

    // Authorize (allow) all domains to consume the content
    resp.addHeader("Access-Control-Allow-Origin", "*");
    resp.addHeader("Access-Control-Allow-Methods", "GET, OPTIONS, HEAD, PUT, POST, DELETE");

    // For HTTP OPTIONS verb/method reply with ACCEPTED status code -- per CORS handshake
    if (request.getMethod().equals("OPTIONS")) {
      resp.setStatus(HttpServletResponse.SC_ACCEPTED);
      return;
    }

    // pass the request along the filter chain
    filterChain.doFilter(request, servletResponse);
  }

  @Override
  public void destroy() {}
}