Java tutorial
package com.thinkbiganalytics.metadata.sla.spi.core; /*- * #%L * thinkbig-sla-core * %% * Copyright (C) 2017 ThinkBig Analytics * %% * 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. * #L% */ import com.thinkbiganalytics.alerts.api.Alert; import com.thinkbiganalytics.alerts.sla.AssessmentAlerts; import com.thinkbiganalytics.alerts.spi.AlertManager; import com.thinkbiganalytics.metadata.sla.api.ServiceLevelAgreement; import com.thinkbiganalytics.metadata.sla.api.ServiceLevelAssessment; import com.thinkbiganalytics.metadata.sla.spi.AssessorNotFoundException; import com.thinkbiganalytics.metadata.sla.spi.ServiceLevelAgreementChecker; import com.thinkbiganalytics.metadata.sla.spi.ServiceLevelAgreementProvider; import com.thinkbiganalytics.metadata.sla.spi.ServiceLevelAssessmentProvider; import com.thinkbiganalytics.metadata.sla.spi.ServiceLevelAssessor; import com.thinkbiganalytics.security.role.SecurityRole; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.util.Collections; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; import javax.inject.Inject; import javax.inject.Named; /** */ public class DefaultServiceLevelAgreementChecker implements ServiceLevelAgreementChecker { private static final Logger LOG = LoggerFactory.getLogger(DefaultServiceLevelAgreementChecker.class); @Inject protected ServiceLevelAgreementProvider slaProvider; @Inject protected ServiceLevelAssessmentProvider assessmentProvider; @Inject protected ServiceLevelAssessor assessor; @Inject @Named("kyloAlertManager") protected AlertManager alertManager; //store a ref to the last Assessment ID that was alerted protected Map<ServiceLevelAgreement.ID, ServiceLevelAssessment.ID> alertedAssessments; public DefaultServiceLevelAgreementChecker() { this.alertedAssessments = Collections .synchronizedMap(new LinkedHashMap<ServiceLevelAgreement.ID, ServiceLevelAssessment.ID>()); } /** * Caller should wrap this in commit */ public void checkAgreements() { List<? extends ServiceLevelAgreement> list = slaProvider.getAgreements(); LOG.info("Checking {} service level agreements", list.size()); for (ServiceLevelAgreement agreement : list) { checkAgreement(agreement); } LOG.info("Completed checking SLAs"); } /** * Check the Agreement. Caller needs to wrap this in MetadataAccesss transcation */ public void checkAgreement(ServiceLevelAgreement agreement) { if (agreement != null) { Alert newAlert = null; if (isAssessable(agreement)) { LOG.info("Assessing SLA : " + agreement.getName()); try { ServiceLevelAssessment assessment = assessor.assess(agreement); if (shouldAlert(agreement, assessment)) { newAlert = alertManager.createEntityAlert(AssessmentAlerts.VIOLATION_ALERT_TYPE, Alert.Level.FATAL, "Violation of SLA: " + agreement.getName(), alertManager.createEntityIdentificationAlertContent(agreement.getId().toString(), SecurityRole.ENTITY_TYPE.SLA, assessment.getId())); } } catch (AssessorNotFoundException e) { LOG.info("SLA assessment failed. Assessor Not found: {} - Exception: {}", agreement.getName(), e); } } if (newAlert != null) { // Record this assessment as the latest for this SLA. alertedAssessments.put(agreement.getId(), (ServiceLevelAssessment.ID) newAlert.getContent()); LOG.info("SLA assessment failed: {} - generated alert: {}", agreement.getName(), newAlert.getId()); } } } /** * Determine whether an alert should be generated for this assessment by comparing is to the last one for the same SLA. * * @return true if the alert should be generated */ protected boolean shouldAlert(ServiceLevelAgreement agreement, ServiceLevelAssessment assessment) { boolean shouldAlert = false; try { // Get the last assessment that was created for this SLA (if any). ServiceLevelAssessment previous = null; ServiceLevelAssessment.ID previousId = this.alertedAssessments.get(agreement.getId()); if (previousId != null) { previous = this.assessmentProvider.findServiceLevelAssessment(previousId); } else { previous = this.assessmentProvider.findLatestAssessment(agreement.getId()); } if (previous != null) { if (previous.getAgreement() == null && assessment.getServiceLevelAgreementId() != null) { ServiceLevelAgreement previousAgreement = slaProvider .getAgreement(slaProvider.resolve(assessment.getServiceLevelAgreementId().toString())); } shouldAlert = assessment.compareTo(previous) != 0; } else { shouldAlert = true; } } catch (Exception e) { LOG.error("Error checking shouldAlert for {}. {} ", agreement.getName(), e.getMessage(), e); } return shouldAlert; } private boolean isAssessable(ServiceLevelAgreement agreement) { // TODO: validate that this is a kind of agreement that we assess. Assume we assess all SLAs for now. return true; } }