/**
* 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.hadoop.gateway.filter.rewrite.impl;
import org.apache.hadoop.gateway.filter.AbstractGatewayFilter;
import org.apache.hadoop.gateway.filter.GatewayRequestWrapper;
import org.apache.hadoop.gateway.filter.rewrite.api.UrlRewriteServletContextListener;
import org.apache.hadoop.gateway.filter.rewrite.api.UrlRewriteStreamFilterFactory;
import org.apache.hadoop.gateway.filter.rewrite.api.UrlRewriter;
import org.apache.hadoop.gateway.util.urltemplate.Parser;
import org.apache.hadoop.gateway.util.urltemplate.Resolver;
import org.apache.hadoop.gateway.util.urltemplate.Template;
import javax.servlet.FilterConfig;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URISyntaxException;
import java.util.Collections;
import java.util.Enumeration;
import java.util.List;
public class UrlRewriteRequest extends GatewayRequestWrapper implements Resolver {
private UrlRewriter rewriter;
/**
* Constructs a request object wrapping the given request.
*
* @throws IllegalArgumentException if the request is null
*/
public UrlRewriteRequest( FilterConfig config, HttpServletRequest request ) throws IOException {
super( request );
this.rewriter = UrlRewriteServletContextListener.getUrlRewriter( config.getServletContext() );
}
private Template getSourceUrl() {
Template urlTemplate = null;
StringBuffer urlString = super.getRequestURL();
String queryString = super.getQueryString();
if( queryString != null ) {
urlString.append( '?' );
urlString.append( queryString );
}
try {
urlTemplate = Parser.parse( urlString.toString() );
} catch( URISyntaxException e ) {
//TODO: Proper I18 stack logging.
e.printStackTrace();
// Shouldn't be possible given that the URL is constructed from parts of an existing URL.
urlTemplate = null;
}
return urlTemplate;
}
// Note: Source url was added to the request attributes by the GatewayFilter doFilter method.
private Template getTargetUrl() {
boolean rewriteRequestUrl = true;
Template targetUrl;
if( rewriteRequestUrl ) {
targetUrl = (Template)getAttribute( AbstractGatewayFilter.TARGET_REQUEST_URL_ATTRIBUTE_NAME );
if( targetUrl == null ) {
Template sourceUrl = getSourceUrl();
targetUrl = rewriter.rewrite( this, sourceUrl, UrlRewriter.Direction.IN );
setAttribute( AbstractGatewayFilter.TARGET_REQUEST_URL_ATTRIBUTE_NAME, targetUrl );
}
} else {
targetUrl = (Template)getAttribute( AbstractGatewayFilter.SOURCE_REQUEST_URL_ATTRIBUTE_NAME );
}
return targetUrl;
}
private String[] splitTargetUrl( Template url ) {
Template targetUrl = getTargetUrl();
String s = targetUrl.toString();
return s.split( "\\?" );
}
@Override
public StringBuffer getRequestURL() {
return new StringBuffer( getRequestURI() );
}
@Override
public String getRequestURI() {
String[] split = splitTargetUrl( getTargetUrl() );
if( split.length > 0 ) {
return split[0];
} else {
return "";
}
}
@Override
public String getQueryString() {
String[] split = splitTargetUrl( getTargetUrl() );
if( split.length > 1 ) {
return split[1];
} else {
return null;
}
}
public String rewriteValue( UrlRewriter rewriter, String value ) {
try {
Template input = Parser.parse( value );
Template output = rewriter.rewrite( this, input, UrlRewriter.Direction.IN );
value = output.toString();
} catch( URISyntaxException e ) {
e.printStackTrace();
}
return value;
}
@Override
public String getHeader( String name ) {
String value = super.getHeader( name );
if( value != null ) {
value = rewriteValue( rewriter, super.getHeader( name ) );
}
return value;
}
@SuppressWarnings("unchecked")
public Enumeration getHeaders( String name ) {
return new EnumerationRewriter( rewriter, (Enumeration<String>)super.getHeaders( name ) );
}
@Override
public List<String> resolve( String name ) {
return Collections.EMPTY_LIST;
}
private class EnumerationRewriter implements Enumeration<String> {
private UrlRewriter rewriter;
private Enumeration<String> delegate;
private EnumerationRewriter( UrlRewriter rewriter, Enumeration<String> delegate ) {
this.rewriter = rewriter;
this.delegate = delegate;
}
@Override
public boolean hasMoreElements() {
return delegate.hasMoreElements();
}
@Override
public String nextElement() {
return rewriteValue( rewriter, delegate.nextElement() );
}
}
@Override
public ServletInputStream getInputStream() throws IOException {
InputStream stream = UrlRewriteStreamFilterFactory.create(
getMimeType(), null, super.getInputStream(), rewriter, this, UrlRewriter.Direction.IN );
return new UrlRewriteRequestStream( stream );
}
@Override
public BufferedReader getReader() throws IOException {
return new BufferedReader( new InputStreamReader( getInputStream(), getCharacterEncoding() ) );
}
}