org.springframework.cloud.task.batch.partition.DeployerStepExecutionHandler.java Source code

Introduction

Here is the source code for org.springframework.cloud.task.batch.partition.DeployerStepExecutionHandler.java

Source

/*
 * Copyright 2016 the original author or authors.
 *
 * 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.
 */
package org.springframework.cloud.task.batch.partition;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.batch.core.BatchStatus;
import org.springframework.batch.core.JobInterruptedException;
import org.springframework.batch.core.Step;
import org.springframework.batch.core.StepExecution;
import org.springframework.batch.core.explore.JobExplorer;
import org.springframework.batch.core.repository.JobRepository;
import org.springframework.batch.core.step.NoSuchStepException;
import org.springframework.batch.core.step.StepLocator;
import org.springframework.batch.integration.partition.BeanFactoryStepLocator;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.core.env.Environment;
import org.springframework.util.Assert;

/**
 * <p>A {@link CommandLineRunner} used to execute a {@link Step}.  No result is provided
 * directly to the associated {@link DeployerPartitionHandler} as it will obtain the step
 * results directly from the shared job repository.</p>
 *
 * <p>The {@link StepExecution} is rehydrated based on the environment variables provided.
 * Specifically, the following variables are required:</p>
 * <ul>
 *     <li>{@link DeployerPartitionHandler#SPRING_CLOUD_TASK_JOB_EXECUTION_ID}: The id of
 *     the JobExecution.</li>
 *     <li>{@link DeployerPartitionHandler#SPRING_CLOUD_TASK_STEP_EXECUTION_ID}: The id of
 *     the StepExecution.</li>
 *     <li>{@link DeployerPartitionHandler#SPRING_CLOUD_TASK_STEP_NAME}: The id of the
 *     bean definition for the Step to execute.  The id must be found within the provided
 *     {@link BeanFactory}</li>
 * </ul>
 *
 * @author Michael Minella
 */
public class DeployerStepExecutionHandler implements CommandLineRunner {

    private JobExplorer jobExplorer;

    private JobRepository jobRepository;

    private Log logger = LogFactory.getLog(DeployerStepExecutionHandler.class);

    @Autowired
    private Environment environment;

    private StepLocator stepLocator;

    public DeployerStepExecutionHandler(BeanFactory beanFactory, JobExplorer jobExplorer,
            JobRepository jobRepository) {
        Assert.notNull(beanFactory, "A beanFactory is required");
        Assert.notNull(jobExplorer, "A jobExplorer is required");
        Assert.notNull(jobRepository, "A jobRepository is required");

        this.stepLocator = new BeanFactoryStepLocator();
        ((BeanFactoryStepLocator) this.stepLocator).setBeanFactory(beanFactory);

        this.jobExplorer = jobExplorer;
        this.jobRepository = jobRepository;
    }

    @Override
    public void run(String... args) throws Exception {

        validateRequest();

        Long jobExecutionId = Long
                .parseLong(environment.getProperty(DeployerPartitionHandler.SPRING_CLOUD_TASK_JOB_EXECUTION_ID));
        Long stepExecutionId = Long
                .parseLong(environment.getProperty(DeployerPartitionHandler.SPRING_CLOUD_TASK_STEP_EXECUTION_ID));
        StepExecution stepExecution = jobExplorer.getStepExecution(jobExecutionId, stepExecutionId);

        if (stepExecution == null) {
            throw new NoSuchStepException(String.format(
                    "No StepExecution could be located for step execution id %s within job execution %s",
                    stepExecutionId, jobExecutionId));
        }

        String stepName = environment.getProperty(DeployerPartitionHandler.SPRING_CLOUD_TASK_STEP_NAME);
        Step step = stepLocator.getStep(stepName);

        try {
            logger.debug(String.format("Executing step %s with step execution id %s and job execution id %s",
                    stepExecution.getStepName(), stepExecutionId, jobExecutionId));

            step.execute(stepExecution);
        } catch (JobInterruptedException e) {
            stepExecution.setStatus(BatchStatus.STOPPED);
            jobRepository.update(stepExecution);
        } catch (Throwable e) {
            stepExecution.addFailureException(e);
            stepExecution.setStatus(BatchStatus.FAILED);
            jobRepository.update(stepExecution);
        }
    }

    private void validateRequest() {
        Assert.isTrue(environment.containsProperty(DeployerPartitionHandler.SPRING_CLOUD_TASK_JOB_EXECUTION_ID),
                "A job execution id is required");
        Assert.isTrue(environment.containsProperty(DeployerPartitionHandler.SPRING_CLOUD_TASK_STEP_EXECUTION_ID),
                "A step execution id is required");
        Assert.isTrue(environment.containsProperty(DeployerPartitionHandler.SPRING_CLOUD_TASK_STEP_NAME),
                "A step name is required");

        Assert.isTrue(
                this.stepLocator.getStepNames()
                        .contains(environment.getProperty(DeployerPartitionHandler.SPRING_CLOUD_TASK_STEP_NAME)),
                "The step requested cannot be found in the provided BeanFactory");
    }
}