/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-09 Wolfgang M. Meier
* wolfgang@exist-db.org
* http://exist.sourceforge.net
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id$
*/
package org.exist.xquery.functions.request;
import org.apache.log4j.Logger;
import org.exist.dom.QName;
import org.exist.http.servlets.RequestWrapper;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.Variable;
import org.exist.xquery.XPathException;
import org.exist.xquery.XPathUtil;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.JavaObjectValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;
/**
* @author Alain Pannetier <alain.m.pannetier@gmail.com>
*
* Adjusted and Committed by Adam Retter <adam.retter@devon.gov.uk>
*/
public class GetHeader extends BasicFunction {
protected static final Logger logger = Logger.getLogger(GetHeader.class);
public final static FunctionSignature signature = new FunctionSignature(
new QName("get-header", RequestModule.NAMESPACE_URI,
RequestModule.PREFIX),
"Returns the HTTP request header identified by $header-name. The list of all "
+ "headers included in the HTTP request are available through the "
+ "request:get-header-names function.",
new SequenceType[] {
new FunctionParameterSequenceType("header-name", Type.STRING, Cardinality.EXACTLY_ONE, "The HTTP request header name")
},
new FunctionReturnSequenceType(Type.STRING, Cardinality.ZERO_OR_ONE, "the HTTP request header value"));
public GetHeader(XQueryContext context) {
super(context, signature);
}
/*
* (non-Javadoc)
*
* @see org.exist.xquery.BasicFunction#eval(org.exist.xquery.value.Sequence[],
* org.exist.xquery.value.Sequence)
*/
public Sequence eval(Sequence[] args, Sequence contextSequence)
throws XPathException {
final RequestModule myModule = (RequestModule) context
.getModule(RequestModule.NAMESPACE_URI);
// request object is read from global variable $request
final Variable var = myModule.resolveVariable(RequestModule.REQUEST_VAR);
if (var == null || var.getValue() == null
|| var.getValue().getItemType() != Type.JAVA_OBJECT)
{throw new XPathException(this,
"Variable $request is not bound to an Java object.");}
// get parameters
final String param = args[0].getStringValue();
final JavaObjectValue value = (JavaObjectValue) var.getValue().itemAt(0);
if (value.getObject() instanceof RequestWrapper) {
final String headerValue = ((RequestWrapper) value.getObject())
.getHeader(param);
if (headerValue == null) {
return Sequence.EMPTY_SEQUENCE;
} else {
return XPathUtil.javaObjectToXPath(headerValue, null, false);
}
} else
{throw new XPathException(
"Variable $request is not bound to a Request object.");}
}
}