engine-d/src/main/java/org/onap/holmes/engine/manager/DroolsEngine.java

   1 /**\r
   2  * Copyright 2017 ZTE Corporation.\r
   3  *\r
   4  * Licensed under the Apache License, Version 2.0 (the "License");\r
   5  * you may not use this file except in compliance with the License.\r
   6  * You may obtain a copy of the License at\r
   7  *\r
   8  * http://www.apache.org/licenses/LICENSE-2.0\r
   9  *\r
  10  * Unless required by applicable law or agreed to in writing, software\r
  11  * distributed under the License is distributed on an "AS IS" BASIS,\r
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
  13  * See the License for the specific language governing permissions and\r
  14  * limitations under the License.\r
  15  */\r
  16 package org.onap.holmes.engine.manager;\r
  17 \r
  18 \r
  19 import java.io.StringReader;\r
  20 import java.util.HashSet;\r
  21 import java.util.List;\r
  22 import java.util.Locale;\r
  23 import java.util.Set;\r
  24 import javax.annotation.PostConstruct;\r
  25 import javax.inject.Inject;\r
  26 import lombok.extern.slf4j.Slf4j;\r
  27 import org.drools.KnowledgeBase;\r
  28 import org.drools.KnowledgeBaseConfiguration;\r
  29 import org.drools.KnowledgeBaseFactory;\r
  30 import org.drools.builder.KnowledgeBuilder;\r
  31 import org.drools.builder.KnowledgeBuilderFactory;\r
  32 import org.drools.builder.ResourceType;\r
  33 import org.drools.conf.EventProcessingOption;\r
  34 import org.drools.definition.KnowledgePackage;\r
  35 import org.drools.io.Resource;\r
  36 import org.drools.io.ResourceFactory;\r
  37 import org.drools.runtime.StatefulKnowledgeSession;\r
  38 import org.drools.runtime.rule.FactHandle;\r
  39 import org.jvnet.hk2.annotations.Service;\r
  40 import org.onap.holmes.common.api.stat.VesAlarm;\r
  41 import org.onap.holmes.engine.request.DeployRuleRequest;\r
  42 import org.onap.holmes.common.api.entity.CorrelationRule;\r
  43 import org.onap.holmes.common.exception.CorrelationException;\r
  44 import org.onap.holmes.common.utils.ExceptionUtil;\r
  45 import org.onap.holmes.engine.wrapper.RuleMgtWrapper;\r
  46 \r
  47 @Slf4j\r
  48 @Service\r
  49 public class DroolsEngine {\r
  50 \r
  51     private final static int ENABLE = 1;\r
  52     private final Set<String> packageNames = new HashSet<String>();\r
  53     @Inject\r
  54     private RuleMgtWrapper ruleMgtWrapper;\r
  55     private KnowledgeBase kbase;\r
  56     private KnowledgeBaseConfiguration kconf;\r
  57     private StatefulKnowledgeSession ksession;\r
  58 \r
  59     @PostConstruct\r
  60     private void init() {\r
  61         try {\r
  62             // start engine\r
  63             start();\r
  64         } catch (Exception e) {\r
  65             log.error("Failed to start the service: " + e.getMessage(), e);\r
  66             throw ExceptionUtil.buildExceptionResponse("Failed to start the drools engine!");\r
  67         }\r
  68     }\r
  69 \r
  70     private void start() throws CorrelationException {\r
  71         log.info("Drools Engine Initialize Beginning...");\r
  72 \r
  73         initEngineParameter();\r
  74         initDeployRule();\r
  75 \r
  76         log.info("Business Rule Engine Initialize Successfully.");\r
  77     }\r
  78 \r
  79     public void stop() {\r
  80         this.ksession.dispose();\r
  81     }\r
  82 \r
  83     private void initEngineParameter() {\r
  84         this.kconf = KnowledgeBaseFactory.newKnowledgeBaseConfiguration();\r
  85 \r
  86         this.kconf.setOption(EventProcessingOption.STREAM);\r
  87 \r
  88         this.kconf.setProperty("drools.assertBehaviour", "equality");\r
  89 \r
  90         this.kbase = KnowledgeBaseFactory.newKnowledgeBase("D-ENGINE", this.kconf);\r
  91 \r
  92         this.ksession = kbase.newStatefulKnowledgeSession();\r
  93     }\r
  94 \r
  95     private void initDeployRule() throws CorrelationException {\r
  96         List<CorrelationRule> rules = ruleMgtWrapper.queryRuleByEnable(ENABLE);\r
  97 \r
  98         if (rules.isEmpty()) {\r
  99             return;\r
 100         }\r
 101         for (CorrelationRule rule : rules) {\r
 102             if (rule.getContent() != null) {\r
 103                 deployRuleFromDB(rule.getContent());\r
 104             }\r
 105         }\r
 106     }\r
 107 \r
 108     private void deployRuleFromDB(String ruleContent) throws CorrelationException {\r
 109         StringReader reader = new StringReader(ruleContent);\r
 110         Resource res = ResourceFactory.newReaderResource(reader);\r
 111 \r
 112         KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();\r
 113 \r
 114         kbuilder.add(res, ResourceType.DRL);\r
 115 \r
 116         try {\r
 117 \r
 118             kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());\r
 119         } catch (Exception e) {\r
 120             throw new CorrelationException(e.getMessage(), e);\r
 121         }\r
 122         ksession.fireAllRules();\r
 123     }\r
 124 \r
 125     public synchronized String deployRule(DeployRuleRequest rule, Locale locale)\r
 126         throws CorrelationException {\r
 127         StringReader reader = new StringReader(rule.getContent());\r
 128         Resource res = ResourceFactory.newReaderResource(reader);\r
 129 \r
 130         KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();\r
 131 \r
 132         kbuilder.add(res, ResourceType.DRL);\r
 133 \r
 134         judgeRuleContent(locale, kbuilder, true);\r
 135 \r
 136         String packageName = kbuilder.getKnowledgePackages().iterator().next().getName();\r
 137         try {\r
 138             packageNames.add(packageName);\r
 139             kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());\r
 140         } catch (Exception e) {\r
 141             throw new CorrelationException("Failed to deploy the rule.", e);\r
 142         }\r
 143 \r
 144         ksession.fireAllRules();\r
 145         return packageName;\r
 146     }\r
 147 \r
 148     public synchronized void undeployRule(String packageName, Locale locale)\r
 149         throws CorrelationException {\r
 150 \r
 151         KnowledgePackage pkg = kbase.getKnowledgePackage(packageName);\r
 152 \r
 153         if (null == pkg) {\r
 154             throw new CorrelationException("The rule " + packageName + " does not exist!");\r
 155         }\r
 156 \r
 157         try {\r
 158             kbase.removeKnowledgePackage(pkg.getName());\r
 159         } catch (Exception e) {\r
 160             throw new CorrelationException("Failed to delete the rule: " + packageName, e);\r
 161         }\r
 162         packageNames.remove(pkg.getName());\r
 163     }\r
 164 \r
 165     public void compileRule(String content, Locale locale)\r
 166         throws CorrelationException {\r
 167         StringReader reader = new StringReader(content);\r
 168         Resource res = ResourceFactory.newReaderResource(reader);\r
 169 \r
 170         KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();\r
 171 \r
 172         kbuilder.add(res, ResourceType.DRL);\r
 173 \r
 174         judgeRuleContent(locale, kbuilder, false);\r
 175     }\r
 176 \r
 177     private void judgeRuleContent(Locale locale, KnowledgeBuilder kbuilder, boolean judgePackageName)\r
 178         throws CorrelationException {\r
 179         if (kbuilder.hasErrors()) {\r
 180             String errorMsg = "There are errors in the rule: " + kbuilder.getErrors().toString();\r
 181             log.error(errorMsg);\r
 182             throw new CorrelationException(errorMsg);\r
 183         }\r
 184 \r
 185         String packageName = kbuilder.getKnowledgePackages().iterator().next().getName();\r
 186 \r
 187         if (packageNames.contains(packageName) && judgePackageName) {\r
 188             throw new CorrelationException("The rule " + packageName + " already exists in the drools engine.");\r
 189         }\r
 190     }\r
 191 \r
 192     public void putRaisedIntoStream(VesAlarm raiseAlarm) {\r
 193         FactHandle factHandle = this.ksession.getFactHandle(raiseAlarm);\r
 194         if (factHandle != null) {\r
 195             Object obj = this.ksession.getObject(factHandle);\r
 196             if (obj != null && obj instanceof VesAlarm) {\r
 197                 raiseAlarm.setRootFlag(((VesAlarm) obj).getRootFlag());\r
 198             }\r
 199             this.ksession.retract(factHandle);\r
 200         }\r
 201         this.ksession.insert(raiseAlarm);\r
 202         this.ksession.fireAllRules();\r
 203     }\r
 204 \r
 205 }\r