| /* |
| * Licensed to 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 org.apache.plc4x.java.scraper.triggeredscraper.triggerhandler; |
| |
| import org.apache.plc4x.java.api.PlcConnection; |
| import org.apache.plc4x.java.api.exceptions.PlcConnectionException; |
| import org.apache.plc4x.java.api.exceptions.PlcRuntimeException; |
| import org.apache.plc4x.java.api.messages.PlcReadRequest; |
| import org.apache.plc4x.java.api.messages.PlcReadResponse; |
| import org.apache.plc4x.java.scraper.exception.ScraperException; |
| import org.apache.plc4x.java.scraper.triggeredscraper.TriggeredScrapeJobImpl; |
| import org.apache.plc4x.java.scraper.triggeredscraper.TriggeredScraperTask; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.TimeUnit; |
| |
| /** |
| * holds the handler for the regarding trigger-scraper on rising-trigger edge |
| */ |
| public class TriggerHandler { |
| private static final Logger LOGGER = LoggerFactory.getLogger(TriggerHandler.class); |
| private static final String TRIGGER = "trigger"; |
| |
| private final TriggerConfiguration triggerConfiguration; |
| private final TriggeredScraperTask parentScraperTask; |
| |
| //used to enable trigger only on rising edge |
| private boolean lastTriggerState; |
| |
| public TriggerHandler(String triggerStrategy, TriggeredScrapeJobImpl triggeredScrapeJob,TriggeredScraperTask parentScraperTask) throws ScraperException { |
| this.triggerConfiguration = TriggerConfiguration.createConfiguration(triggerStrategy,triggeredScrapeJob); |
| this.parentScraperTask = parentScraperTask; |
| this.lastTriggerState = false; |
| } |
| |
| /** |
| * checks rising edge of trigger event |
| * @return true on detection of rising edge, false otherwise |
| */ |
| public boolean checkTrigger(){ |
| switch (this.triggerConfiguration.getTriggerType()){ |
| case SCHEDULED: |
| //used base scheduling -> trigger is always true |
| return true; |
| case S7_TRIGGER_VAR: |
| return checkS7TriggerVariable(); |
| default: |
| //should not happen |
| return false; |
| } |
| } |
| |
| /** |
| * acquires the given S7Field from S7 and evaluates if trigger is released |
| * @return true if rising-edge of trigger is detected, false otherwise |
| */ |
| private boolean checkS7TriggerVariable(){ |
| |
| CompletableFuture<PlcConnection> future = CompletableFuture.supplyAsync(() -> { |
| try { |
| return parentScraperTask.getDriverManager().getConnection(parentScraperTask.getConnectionString()); |
| } catch (PlcConnectionException e) { |
| LOGGER.warn("Unable to instantiate connection to " + parentScraperTask.getConnectionString(), e); |
| throw new PlcRuntimeException(e); |
| } |
| }, parentScraperTask.getExecutorService()); |
| PlcConnection connection = null; |
| try { |
| connection = future.get(parentScraperTask.getRequestTimeoutMs(), TimeUnit.MILLISECONDS); |
| LOGGER.trace("Connection to {} established: {}", parentScraperTask.getConnectionString(), connection); |
| PlcReadRequest.Builder builder = connection.readRequestBuilder(); |
| builder.addItem(TRIGGER, triggerConfiguration.getTriggerVariable()); |
| PlcReadResponse response = builder |
| .build() |
| .execute() |
| .get(parentScraperTask.getRequestTimeoutMs(), TimeUnit.MILLISECONDS); |
| |
| //check if trigger condition from TriggerConfiguration is fulfilled |
| boolean trigger = triggerConfiguration.evaluateTrigger(response.getObject(TRIGGER)); |
| |
| //only trigger scraping of data on rising edge of trigger |
| if(trigger && !this.lastTriggerState){ |
| this.lastTriggerState = true; |
| return true; |
| } |
| else{ |
| this.lastTriggerState = trigger; |
| return false; |
| } |
| |
| } catch (Exception e) { |
| // Handle execution exception |
| parentScraperTask.handleException(e); |
| return false; |
| } |
| finally { |
| if (connection != null) { |
| try { |
| connection.close(); |
| } catch (Exception e) { |
| LOGGER.warn("Error on closing connection",e); |
| // intentionally do nothing |
| } |
| } |
| } |
| } |
| |
| |
| |
| |
| |
| |
| } |