/*
* Copyright 2015 Red Hat, Inc. and/or its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
*
* 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.drools.beliefs.bayes.integration;
import org.drools.beliefs.bayes.BayesModeFactory;
import org.drools.beliefs.bayes.BayesModeFactoryImpl;
import org.drools.beliefs.bayes.BayesBeliefSystem;
import org.drools.beliefs.bayes.BayesInstance;
import org.drools.beliefs.bayes.PropertyReference;
import org.drools.beliefs.bayes.runtime.BayesRuntime;
import org.drools.core.BeliefSystemType;
import org.drools.core.SessionConfiguration;
import org.drools.core.common.NamedEntryPoint;
import org.drools.core.impl.StatefulKnowledgeSessionImpl;
import org.drools.core.rule.EntryPointId;
import org.junit.Test;
import org.kie.api.io.ResourceType;
import org.kie.api.runtime.KieSessionConfiguration;
import org.kie.api.runtime.rule.FactHandle;
import org.kie.internal.KnowledgeBase;
import org.kie.internal.KnowledgeBaseFactory;
import org.kie.internal.builder.KnowledgeBuilder;
import org.kie.internal.builder.KnowledgeBuilderFactory;
import org.kie.internal.io.ResourceFactory;
import org.kie.internal.runtime.StatefulKnowledgeSession;
import static junit.framework.TestCase.assertFalse;
import static org.drools.beliefs.bayes.JunctionTreeTest.scaleDouble;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
public class BayesBeliefSystemTest {
@Test
public void testBayes() {
String drl = "package org.drools.defeasible; " +
"import " + Garden.class.getCanonicalName() + "; \n" +
"import " + PropertyReference.class.getCanonicalName() + "; \n" +
"global " + BayesModeFactory.class.getCanonicalName() + " bsFactory; \n" +
"dialect 'mvel'; \n" +
" " +
"rule rule1 when " +
" String( this == 'rule1') \n" +
" g : Garden()" +
"then " +
" System.out.println(\"rule 1\"); \n" +
" insertLogical( new PropertyReference(g, 'cloudy'), bsFactory.create( new double[] {1.0,0.0} ) ); \n " +
"end " +
"rule rule2 when " +
" String( this == 'rule2') \n" +
" g : Garden()" +
"then " +
" System.out.println(\"rule2\"); \n" +
" insertLogical( new PropertyReference(g, 'sprinkler'), bsFactory.create( new double[] {1.0,0.0} ) ); \n " +
"end " +
"rule rule3 when " +
" String( this == 'rule3') \n" +
" g : Garden()" +
"then " +
" System.out.println(\"rule3\"); \n" +
" insertLogical( new PropertyReference(g, 'sprinkler'), bsFactory.create( new double[] {1.0,0.0} ) ); \n " +
"end " +
"rule rule4 when " +
" String( this == 'rule4') \n" +
" g : Garden()" +
"then " +
" System.out.println(\"rule4\"); \n" +
" insertLogical( new PropertyReference(g, 'sprinkler'), bsFactory.create( new double[] {0.0,1.0} ) ); \n " +
"end " +
"\n";
StatefulKnowledgeSessionImpl ksession = (StatefulKnowledgeSessionImpl) getSessionFromString( drl );
NamedEntryPoint ep = (NamedEntryPoint) ksession.getEntryPoint(EntryPointId.DEFAULT.getEntryPointId());
BayesBeliefSystem bayesBeliefSystem = new BayesBeliefSystem( ep, ep.getTruthMaintenanceSystem());
BayesModeFactoryImpl bayesModeFactory = new BayesModeFactoryImpl(bayesBeliefSystem);
ksession.setGlobal( "bsFactory", bayesModeFactory);
BayesRuntime bayesRuntime = ksession.getKieRuntime(BayesRuntime.class);
BayesInstance<Garden> instance = bayesRuntime.createInstance(Garden.class);
assertNotNull( instance );
assertTrue(instance.isDecided());
instance.globalUpdate();
Garden garden = instance.marginalize();
assertTrue( garden.isWetGrass() );
FactHandle fh = ksession.insert( garden );
FactHandle fh1 = ksession.insert( "rule1" );
ksession.fireAllRules();
assertTrue(instance.isDecided());
instance.globalUpdate(); // rule1 has added evidence, update the bayes network
garden = instance.marginalize();
assertTrue(garden.isWetGrass()); // grass was wet before rule1 and continues to be wet
FactHandle fh2 = ksession.insert( "rule2" ); // applies 2 logical insertions
ksession.fireAllRules();
assertTrue(instance.isDecided());
instance.globalUpdate();
garden = instance.marginalize();
assertFalse(garden.isWetGrass() ); // new evidence means grass is no longer wet
FactHandle fh3 = ksession.insert( "rule3" ); // adds an additional support for the sprinkler, belief set of 2
ksession.fireAllRules();
assertTrue(instance.isDecided());
instance.globalUpdate();
garden = instance.marginalize();
assertFalse(garden.isWetGrass() ); // nothing has changed
FactHandle fh4 = ksession.insert( "rule4" ); // rule4 introduces a conflict, and the BayesFact becomes undecided
ksession.fireAllRules();
assertFalse(instance.isDecided());
try {
instance.globalUpdate();
fail( "The BayesFact is undecided, it should throw an exception, as it cannot be updated." );
} catch ( Exception e ) {
// this should fail
}
ksession.delete( fh4 ); // the conflict is resolved, so it should be decided again
ksession.fireAllRules();
assertTrue(instance.isDecided());
instance.globalUpdate();
garden = instance.marginalize();
assertFalse(garden.isWetGrass() );// back to grass is not wet
ksession.delete( fh2 ); // takes the sprinkler belief set back to 1
ksession.fireAllRules();
instance.globalUpdate();
garden = instance.marginalize();
assertFalse(garden.isWetGrass() ); // still grass is not wet
ksession.delete( fh3 ); // no sprinkler support now
ksession.fireAllRules();
instance.globalUpdate();
garden = instance.marginalize();
assertTrue(garden.isWetGrass()); // grass is wet again
}
protected StatefulKnowledgeSession getSessionFromString( String drlString) {
KnowledgeBuilder kBuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
kBuilder.add( ResourceFactory.newByteArrayResource(drlString.getBytes()),
ResourceType.DRL );
kBuilder.add( ResourceFactory.newClassPathResource("Garden.xmlbif", AssemblerTest.class), ResourceType.BAYES );
if ( kBuilder.hasErrors() ) {
System.err.println( kBuilder.getErrors() );
fail();
}
KnowledgeBase kBase = KnowledgeBaseFactory.newKnowledgeBase();
kBase.addKnowledgePackages( kBuilder.getKnowledgePackages() );
KieSessionConfiguration ksConf = KnowledgeBaseFactory.newKnowledgeSessionConfiguration();
((SessionConfiguration) ksConf).setBeliefSystemType( BeliefSystemType.DEFEASIBLE );
StatefulKnowledgeSession kSession = kBase.newStatefulKnowledgeSession( ksConf, null );
return kSession;
}
protected StatefulKnowledgeSession getSession( String ruleFile ) {
KnowledgeBuilder kBuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
kBuilder.add( ResourceFactory.newClassPathResource( ruleFile ),
ResourceType.DRL );
if ( kBuilder.hasErrors() ) {
System.err.println( kBuilder.getErrors() );
fail();
}
KnowledgeBase kBase = KnowledgeBaseFactory.newKnowledgeBase();
kBase.addKnowledgePackages( kBuilder.getKnowledgePackages() );
KieSessionConfiguration ksConf = KnowledgeBaseFactory.newKnowledgeSessionConfiguration();
((SessionConfiguration) ksConf).setBeliefSystemType( BeliefSystemType.DEFEASIBLE );
StatefulKnowledgeSession kSession = kBase.newStatefulKnowledgeSession( ksConf, null );
return kSession;
}
}