1 files changed, 285 insertions, 0 deletions
diff --git a/engine-d/src/main/java/org/onap/holmes/engine/manager/DroolsEngine.java b/engine-d/src/main/java/org/onap/holmes/engine/manager/DroolsEngine.java
new file mode 100644
index 0000000..c8835cc
--- /dev/null
+++ b/engine-d/src/main/java/org/onap/holmes/engine/manager/DroolsEngine.java
@@ -0,0 +1,285 @@
+/**
+ * Copyright 2017 ZTE Corporation.
+ *
+ * Licensed 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.onap.holmes.engine.manager;
+
+
+import java.io.Serializable;
+import java.io.StringReader;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Set;
+import javax.annotation.PostConstruct;
+import javax.inject.Inject;
+import javax.jms.Connection;
+import javax.jms.ConnectionFactory;
+import javax.jms.Destination;
+import javax.jms.JMSException;
+import javax.jms.Message;
+import javax.jms.MessageConsumer;
+import javax.jms.MessageListener;
+import javax.jms.Session;
+import lombok.extern.slf4j.Slf4j;
+import org.apache.activemq.ActiveMQConnectionFactory;
+import org.apache.activemq.command.ActiveMQObjectMessage;
+import org.drools.KnowledgeBase;
+import org.drools.KnowledgeBaseConfiguration;
+import org.drools.KnowledgeBaseFactory;
+import org.drools.builder.KnowledgeBuilder;
+import org.drools.builder.KnowledgeBuilderFactory;
+import org.drools.builder.ResourceType;
+import org.drools.conf.EventProcessingOption;
+import org.drools.definition.KnowledgePackage;
+import org.drools.io.Resource;
+import org.drools.io.ResourceFactory;
+import org.drools.runtime.StatefulKnowledgeSession;
+import org.drools.runtime.rule.FactHandle;
+import org.glassfish.hk2.api.IterableProvider;
+import org.jvnet.hk2.annotations.Service;
+import org.onap.holmes.engine.request.DeployRuleRequest;
+import org.onap.holmes.common.api.entity.CorrelationRule;
+import org.onap.holmes.common.api.stat.Alarm;
+import org.onap.holmes.common.config.MQConfig;
+import org.onap.holmes.common.constant.AlarmConst;
+import org.onap.holmes.common.exception.CorrelationException;
+import org.onap.holmes.common.utils.ExceptionUtil;
+import org.onap.holmes.engine.wrapper.RuleMgtWrapper;
+
+@Slf4j
+@Service
+public class DroolsEngine {
+
+    private final static int ENABLE = 1;
+    private final Set<String> packageNames = new HashSet<String>();
+    @Inject
+    private RuleMgtWrapper ruleMgtWrapper;
+    private KnowledgeBase kbase;
+    private KnowledgeBaseConfiguration kconf;
+    private StatefulKnowledgeSession ksession;
+    @Inject
+    private IterableProvider<MQConfig> mqConfigProvider;
+    private ConnectionFactory connectionFactory;
+
+    @PostConstruct
+    private void init() {
+        try {
+            // 1. start engine
+            start();
+            // 2. start mq listener
+            registerAlarmTopicListener();
+        } catch (Exception e) {
+            log.error("Failed to start the service: " + e.getMessage(), e);
+            throw ExceptionUtil.buildExceptionResponse("Failed to start the drools engine!");
+        }
+    }
+
+    private void registerAlarmTopicListener() {
+        String brokerURL =
+            "tcp://" + mqConfigProvider.get().brokerIp + ":" + mqConfigProvider.get().brokerPort;
+        connectionFactory = new ActiveMQConnectionFactory(mqConfigProvider.get().brokerUsername,
+            mqConfigProvider.get().brokerPassword, brokerURL);
+
+        AlarmMqMessageListener listener = new AlarmMqMessageListener();
+        listener.receive();
+    }
+
+
+    private void start() throws CorrelationException {
+        log.info("Drools Engine Initialize Beginning...");
+
+        initEngineParameter();
+        initDeployRule();
+
+        log.info("Business Rule Engine Initialize Successfully.");
+    }
+
+    public void stop() {
+        this.ksession.dispose();
+    }
+
+    private void initEngineParameter() {
+        this.kconf = KnowledgeBaseFactory.newKnowledgeBaseConfiguration();
+
+        this.kconf.setOption(EventProcessingOption.STREAM);
+
+        this.kconf.setProperty("drools.assertBehaviour", "equality");
+
+        this.kbase = KnowledgeBaseFactory.newKnowledgeBase("D-ENGINE", this.kconf);
+
+        this.ksession = kbase.newStatefulKnowledgeSession();
+    }
+
+    private void initDeployRule() throws CorrelationException {
+        List<CorrelationRule> rules = ruleMgtWrapper.queryRuleByEnable(ENABLE);
+
+        if (rules.isEmpty()) {
+            return;
+        }
+        for (CorrelationRule rule : rules) {
+            if (rule.getContent() != null) {
+                deployRuleFromDB(rule.getContent());
+            }
+        }
+    }
+
+    private void deployRuleFromDB(String ruleContent) throws CorrelationException {
+        StringReader reader = new StringReader(ruleContent);
+        Resource res = ResourceFactory.newReaderResource(reader);
+
+        KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
+
+        kbuilder.add(res, ResourceType.DRL);
+
+        try {
+
+            kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());
+        } catch (Exception e) {
+            throw new CorrelationException(e.getMessage(), e);
+        }
+        ksession.fireAllRules();
+    }
+
+    public synchronized String deployRule(DeployRuleRequest rule, Locale locale)
+        throws CorrelationException {
+        StringReader reader = new StringReader(rule.getContent());
+        Resource res = ResourceFactory.newReaderResource(reader);
+
+        KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
+
+        kbuilder.add(res, ResourceType.DRL);
+
+        judgeRuleContent(locale, kbuilder, true);
+
+        String packageName = kbuilder.getKnowledgePackages().iterator().next().getName();
+        try {
+            packageNames.add(packageName);
+            kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());
+        } catch (Exception e) {
+            throw new CorrelationException("Failed to deploy the rule.", e);
+        }
+
+        ksession.fireAllRules();
+        return packageName;
+    }
+
+    public synchronized void undeployRule(String packageName, Locale locale)
+        throws CorrelationException {
+
+        KnowledgePackage pkg = kbase.getKnowledgePackage(packageName);
+
+        if (null == pkg) {
+            throw new CorrelationException("The rule " + packageName + " does not exist!");
+        }
+
+        try {
+            kbase.removeKnowledgePackage(pkg.getName());
+        } catch (Exception e) {
+            throw new CorrelationException("Failed to delete the rule: " + packageName, e);
+        }
+    }
+
+    public void compileRule(String content, Locale locale)
+        throws CorrelationException {
+        StringReader reader = new StringReader(content);
+        Resource res = ResourceFactory.newReaderResource(reader);
+
+        KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
+
+        kbuilder.add(res, ResourceType.DRL);
+
+        judgeRuleContent(locale, kbuilder, false);
+    }
+
+    private void judgeRuleContent(Locale locale, KnowledgeBuilder kbuilder, boolean judgePackageName)
+        throws CorrelationException {
+        if (kbuilder.hasErrors()) {
+            String errorMsg = "There are errors in the rule: " + kbuilder.getErrors().toString();
+            log.error(errorMsg);
+            throw new CorrelationException(errorMsg);
+        }
+
+        String packageName = kbuilder.getKnowledgePackages().iterator().next().getName();
+
+        if (packageNames.contains(packageName) && judgePackageName) {
+            throw new CorrelationException("The rule " + packageName + " already exists in the drools engine.");
+        }
+    }
+
+    public void putRaisedIntoStream(Alarm raiseAlarm) {
+        FactHandle factHandle = this.ksession.getFactHandle(raiseAlarm);
+        if (factHandle != null) {
+            this.ksession.retract(factHandle);
+        }
+        this.ksession.insert(raiseAlarm);
+        this.ksession.fireAllRules();
+    }
+
+    class AlarmMqMessageListener implements MessageListener {
+
+        private Connection connection = null;
+        private Session session = null;
+        private Destination destination = null;
+        private MessageConsumer consumer = null;
+
+        private void initialize() throws JMSException {
+            connection = connectionFactory.createConnection();
+            session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
+            destination = session.createTopic(AlarmConst.MQ_TOPIC_NAME_ALARM);
+            consumer = session.createConsumer(destination);
+            connection.start();
+        }
+
+        public void receive() {
+            try {
+                initialize();
+                consumer.setMessageListener(this);
+            } catch (JMSException e) {
+                log.error("Failed to connect to the MQ service : " + e.getMessage(), e);
+                try {
+                    close();
+                } catch (JMSException e1) {
+                    log.error("Failed close connection  " + e1.getMessage(), e1);
+                }
+            }
+        }
+
+        public void onMessage(Message arg0) {
+            ActiveMQObjectMessage objectMessage = (ActiveMQObjectMessage) arg0;
+            try {
+                Serializable object = objectMessage.getObject();
+
+                if (object instanceof Alarm) {
+                    Alarm alarm = (Alarm) object;
+                    putRaisedIntoStream(alarm);
+                }
+            } catch (JMSException e) {
+                log.error("Failed get object : " + e.getMessage(), e);
+            }
+        }
+
+        private void close() throws JMSException {
+            if (consumer != null) {
+                consumer.close();
+            }
+            if (session != null) {
+                session.close();
+            }
+            if (connection != null) {
+                connection.close();
+            }
+        }
+    }
+}