/*
* 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 io.covert.dns.filtering;
import java.util.Map;
import org.apache.commons.jexl2.Expression;
import org.apache.commons.jexl2.JexlContext;
import org.apache.commons.jexl2.JexlEngine;
import org.apache.commons.jexl2.MapContext;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.type.TypeReference;
public class Filter {
static
{
// the WARN messages occur if the expression contains a var that is not in the record.
// not good for many expressions, esp ones filtering on IP GEO info
Logger.getLogger("org.apache.commons.jexl2").setLevel(Level.ERROR);
}
JexlEngine engine = new JexlEngine();;
Expression expr;
public Filter(String jexlExpression)
{
expr = engine.createExpression(jexlExpression);
}
public boolean filter(Map<String, Object> record)
{
JexlContext context = new MapContext(record);
Object val = expr.evaluate(context);
if (val instanceof Boolean) {
Boolean bool = (Boolean) val;
return bool;
}
return false;
}
}