Java tutorial
/** * Copyright 2015 StreamSets Inc. * * Licensed under 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 com.streamsets.datacollector.execution.alerts; import com.codahale.metrics.Gauge; import com.codahale.metrics.MetricRegistry; import com.google.common.base.Charsets; import com.google.common.io.Resources; import com.streamsets.datacollector.alerts.AlertsUtil; import com.streamsets.datacollector.config.DataRuleDefinition; import com.streamsets.datacollector.config.RuleDefinition; import com.streamsets.datacollector.email.EmailException; import com.streamsets.datacollector.email.EmailSender; import com.streamsets.datacollector.execution.EventListenerManager; import com.streamsets.datacollector.main.RuntimeInfo; import com.streamsets.datacollector.metrics.MetricsConfigurator; import com.streamsets.datacollector.util.PipelineException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.inject.Named; import java.io.IOException; import java.io.PrintWriter; import java.io.StringWriter; import java.net.URL; import java.text.SimpleDateFormat; import java.util.Date; import java.util.List; import java.util.Locale; public class AlertManager { private static Logger LOG = LoggerFactory.getLogger(AlertManager.class); private final String pipelineName; private final String revision; private final EmailSender emailSender; private final MetricRegistry metrics; private final RuntimeInfo runtimeInfo; private final EventListenerManager eventListenerManager; public AlertManager(@Named("name") String pipelineName, @Named("rev") String revision, EmailSender emailSender, MetricRegistry metrics, RuntimeInfo runtimeInfo, EventListenerManager eventListenerManager) { this.pipelineName = pipelineName; this.revision = revision; this.emailSender = emailSender; this.metrics = metrics; this.runtimeInfo = runtimeInfo; this.eventListenerManager = eventListenerManager; } public void alert(List<String> emailIds, Throwable throwable) { StringWriter stringWriter = new StringWriter(); PrintWriter printWriter = new PrintWriter(stringWriter); throwable.printStackTrace(printWriter); String description = stringWriter.toString(); String subject = "ERROR: " + throwable; long timestamp = System.currentTimeMillis(); String errorCode = "UNKNOWN"; if (throwable instanceof PipelineException) { PipelineException pipelineException = (PipelineException) throwable; timestamp = pipelineException.getErrorMessage().getTimestamp(); subject = "ERROR: " + pipelineException.getLocalizedMessage(); errorCode = pipelineException.getErrorCode().getCode(); } try { URL url = Resources.getResource(EmailConstants.ALERT_ERROR_EMAIL_TEMPLATE); String emailBody = Resources.toString(url, Charsets.UTF_8); java.text.DateFormat dateTimeFormat = new SimpleDateFormat(EmailConstants.DATE_MASK, Locale.ENGLISH); emailBody = emailBody.replace(EmailConstants.ERROR_CODE, errorCode) .replace(EmailConstants.TIME_KEY, dateTimeFormat.format(new Date(timestamp))) .replace(EmailConstants.PIPELINE_NAME_KEY, pipelineName) .replace(EmailConstants.DESCRIPTION_KEY, description).replace(EmailConstants.URL_KEY, runtimeInfo.getBaseHttpUrl() + EmailConstants.PIPELINE_URL + pipelineName); subject = EmailConstants.STREAMSETS_DATA_COLLECTOR_ALERT + subject; if (LOG.isDebugEnabled()) { LOG.debug("Email Alert: subject = " + subject + ", body = " + emailBody); } if (emailSender == null) { LOG.error("Email Sender is not configured. Alert with message '{}' will not be sent via email:", emailBody, throwable); } else { emailSender.send(emailIds, subject, emailBody); } } catch (EmailException | IOException e) { LOG.error("Error sending alert email, reason: {}", e.toString(), e); //Log error and move on. This should not stop the pipeline. } } public void alert(Object value, List<String> emailIds, RuleDefinition ruleDefinition) { Gauge<Object> gauge = MetricsConfigurator.getGauge(metrics, AlertsUtil.getAlertGaugeName(ruleDefinition.getId())); if (gauge == null) { Gauge<Object> alertResponseGauge = AlertManagerHelper.createAlertResponseGauge(pipelineName, revision, metrics, value, ruleDefinition); eventListenerManager.broadcastAlerts(new AlertInfo(pipelineName, ruleDefinition, alertResponseGauge)); //send email the first time alert is triggered if (ruleDefinition.isSendEmail()) { try { URL url = Resources.getResource(EmailConstants.METRIC_EMAIL_TEMPLATE); String emailBody = Resources.toString(url, Charsets.UTF_8); java.text.DateFormat dateTimeFormat = new SimpleDateFormat(EmailConstants.DATE_MASK, Locale.ENGLISH); emailBody = emailBody.replace(EmailConstants.ALERT_VALUE_KEY, String.valueOf(value)) .replace(EmailConstants.TIME_KEY, dateTimeFormat.format(new Date((Long) System.currentTimeMillis()))) .replace(EmailConstants.PIPELINE_NAME_KEY, pipelineName) .replace(EmailConstants.CONDITION_KEY, ruleDefinition.getCondition()) .replace(EmailConstants.URL_KEY, runtimeInfo.getBaseHttpUrl() + EmailConstants.PIPELINE_URL + pipelineName); if (ruleDefinition instanceof DataRuleDefinition) { emailBody = emailBody.replace(EmailConstants.ALERT_NAME_KEY, ((DataRuleDefinition) ruleDefinition).getLabel()); } else { emailBody = emailBody.replace(EmailConstants.ALERT_NAME_KEY, ruleDefinition.getAlertText()); } if (emailSender == null) { LOG.error( "Email Sender is not configured. Alert '{}' with message '{}' will not be sent via email.", ruleDefinition.getId(), emailBody); } else { emailSender.send(emailIds, EmailConstants.STREAMSETS_DATA_COLLECTOR_ALERT + ruleDefinition.getAlertText(), emailBody); } } catch (EmailException | IOException e) { LOG.error("Error sending alert email, reason: {}", e.toString(), e); //Log error and move on. This should not stop the pipeline. } } } else { AlertManagerHelper.updateAlertGauge(gauge, value, ruleDefinition); } } public void alertException(Object value, RuleDefinition ruleDefinition) { AlertManagerHelper.alertException(pipelineName, revision, metrics, value, ruleDefinition); } }