/*
* Copyright 2014 Cisco Systems, Inc.
*
* 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
*
* 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 com.cisco.oss.foundation.http.server.jetty.filters;
import com.cisco.oss.foundation.configuration.ConfigurationFactory;
import com.cisco.oss.foundation.http.server.AbstractInfraHttpFilter;
import com.google.common.base.Joiner;
import com.google.common.base.Strings;
import com.google.common.collect.Lists;
import org.apache.commons.configuration.Configuration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.servlet.*;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
/**
* implementation of CORS - http://en.wikipedia.org/wiki/Cross-origin_resource_sharing
*/
public class CrossOriginFilter extends AbstractInfraHttpFilter {
private static final Logger LOGGER = LoggerFactory.getLogger(CrossOriginFilter.class);
private org.eclipse.jetty.servlets.CrossOriginFilter crossOriginFilter = new org.eclipse.jetty.servlets.CrossOriginFilter();
private String serviceName;
public CrossOriginFilter(String serviceName){
super(serviceName);
try {
crossOriginFilter.init(new CrossOriginFilterConfig(serviceName));
} catch (ServletException e) {
LOGGER.error("can't init crosee origin filter", e);
}
}
@Override
protected String getKillSwitchFlag() {
return "http.crossOriginFilter.isEnabled";
}
@Override
protected void doFilterImpl(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
crossOriginFilter.doFilter(request, response, chain);
}
@Override
protected boolean isEnabledByDefault() {
return false;
}
private static class CrossOriginFilterConfig implements FilterConfig{
private String serviceName;
public CrossOriginFilterConfig(String serviceName) {
this.serviceName = serviceName;
}
@Override
public String getFilterName() {
return "CrossOriginFilter";
}
@Override
public ServletContext getServletContext() {
return null;
}
@Override
public String getInitParameter(String name) {
Configuration configuration = ConfigurationFactory.getConfiguration();
String prefix = serviceName + ".http.crossOriginFilter.";
if(org.eclipse.jetty.servlets.CrossOriginFilter.ALLOWED_ORIGINS_PARAM.equals(name)){
String paramName = prefix + "allowedOrigins";
return getArrayAsString(configuration, paramName);
}else if(org.eclipse.jetty.servlets.CrossOriginFilter.ALLOWED_METHODS_PARAM.equals(name)){
String paramName = prefix + "allowedMethods";
return getArrayAsString(configuration, paramName);
}else if(org.eclipse.jetty.servlets.CrossOriginFilter.ALLOWED_HEADERS_PARAM.equals(name)){
String paramName = prefix + "allowedHeaders";
return getArrayAsString(configuration, paramName);
}else if(org.eclipse.jetty.servlets.CrossOriginFilter.PREFLIGHT_MAX_AGE_PARAM.equals(name)){
return configuration.getString(prefix+"preflightMaxAge","1800");
}else if(org.eclipse.jetty.servlets.CrossOriginFilter.ALLOW_CREDENTIALS_PARAM.equals(name)){
return configuration.getString(prefix+"allowCredentials","true");
}else if(org.eclipse.jetty.servlets.CrossOriginFilter.EXPOSED_HEADERS_PARAM.equals(name)){
String paramName = prefix + "exposedHeaders";
return getArrayAsString(configuration, paramName);
}else if(org.eclipse.jetty.servlets.CrossOriginFilter.CHAIN_PREFLIGHT_PARAM.equals(name)){
return configuration.getString(prefix+"chainPreflight","false");
}
return null;
}
private String getArrayAsString(Configuration configuration, String paramName) {
List<String> values = Lists.newArrayList();
Configuration subset = configuration.subset(paramName);
@SuppressWarnings("unchecked")
Iterator<String> keys = subset.getKeys();
while (keys.hasNext()) {
String key = (String) keys.next();
values.add(subset.getString(key));
}
Joiner joiner = Joiner.on(',').skipNulls();
String result = joiner.join(values);
if(Strings.isNullOrEmpty(result)){
result = null;
}
return result;
}
@Override
public Enumeration<String> getInitParameterNames() {
// TODO Auto-generated method stub
return null;
}
}
}