org.apache.pulsar.io.batchdiscovery.CronTriggerer Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* 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
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* specific language governing permissions and limitations
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*/
package org.apache.pulsar.io.batchdiscovery;
import java.util.Map;
import java.util.Objects;
import java.util.function.Consumer;
import lombok.extern.slf4j.Slf4j;
import org.apache.pulsar.io.core.BatchSourceTriggerer;
import org.apache.pulsar.io.core.SourceContext;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import org.springframework.scheduling.support.CronTrigger;
/**
* This is an implementation of BatchSourceTriggerer that triggers based on a cron expression.
* BatchSource developers using this should pass the json string of a map that contains
* "__CRON__" key with the appropriate cron expression. The triggerer will trigger based on this expression.
*
*/
@Slf4j
public class CronTriggerer implements BatchSourceTriggerer {
public static final String CRON_KEY = "__CRON__";
private String cronExpression;
private ThreadPoolTaskScheduler scheduler;
@Override
public void init(Map config, SourceContext sourceContext) {
if (config == null || config.containsKey(CRON_KEY)) {
cronExpression = (String) Objects.requireNonNull(config).get(CRON_KEY);
} else {
throw new IllegalArgumentException("Cron Trigger is not provided with Cron String");
}
scheduler = new ThreadPoolTaskScheduler();
scheduler.setThreadNamePrefix(String.format("%s/%s/%s-cron-triggerer-",
sourceContext.getTenant(), sourceContext.getNamespace(), sourceContext.getSourceName()));
log.info("Initialized CronTrigger with expression: {}", cronExpression);
}
@Override
public void start(Consumer trigger) {
scheduler.initialize();
scheduler.schedule(() -> trigger.accept("CRON"), new CronTrigger(cronExpression));
}
@Override
public void stop() {
if (scheduler != null) {
scheduler.shutdown();
}
}
}