/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-2009 The eXist Project
* http://exist-db.org
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $Id$
*/
package org.exist.xquery.functions.fn;
import java.util.Map;
import org.apache.log4j.Logger;
import org.exist.dom.QName;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.Function;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.StringValue;
import org.exist.xquery.value.Type;
import org.exist.xquery.value.ValueSequence;
public class FunEnvironment extends BasicFunction {
protected static final Logger logger = Logger.getLogger(FunEnvironment.class);
public final static FunctionSignature signature[] = {
new FunctionSignature(
new QName("available-environment-variables", Function.BUILTIN_FUNCTION_NS),
"Returns a list of environment variable names.",
null,
new FunctionReturnSequenceType(Type.STRING, Cardinality.ZERO_OR_MORE,
"Returns a sequence of strings, being the names of the environment variables. User must be DBA.")
),
new FunctionSignature(
new QName("environment-variable", Function.BUILTIN_FUNCTION_NS),
"Returns the value of a system environment variable, if it exists.",
new SequenceType[] {
new FunctionParameterSequenceType("name", Type.STRING,
Cardinality.EXACTLY_ONE, "Name of environment variable.")
},
new FunctionReturnSequenceType(Type.STRING, Cardinality.ZERO, "Corrensponding value of the environment variable, "
+ "if there is no environment variable with a matching name, the function returns the empty sequence. User must be DBA.")
)
};
public FunEnvironment(XQueryContext context, FunctionSignature signature) {
super(context, signature);
}
@Override
public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {
if (!context.getSubject().hasDbaRole()) {
final String txt = "Permission denied, calling user '" + context.getSubject().getName() + "' must be a DBA to call this function.";
logger.error(txt);
return Sequence.EMPTY_SEQUENCE;
}
if (isCalledAs("available-environment-variables")) {
final Sequence result = new ValueSequence();
final Map<String, String> env = context.getEnvironmentVariables();
for (final String key : env.keySet()) {
result.add(new StringValue(key));
}
return result;
} else {
if (args[0].isEmpty()) {
return Sequence.EMPTY_SEQUENCE;
}
final String parameter = args[0].itemAt(0).getStringValue();
final String value = context.getEnvironmentVariables().get(parameter);
if (value == null) {
return Sequence.EMPTY_SEQUENCE;
}
return new StringValue(value);
}
}
}