如何从休息服务开始批处理。 afterJob 运行但 EnableBatchProcessing 仅在部署后运行

Question

我按照教程https://spring.io/guides/gs/batch-processing/ which basically reads a spreadsheet and insert the data in database once the application is started. I want to execute the reading process every time a rest service is evoked, so I added a controller in this application. To call the job I followed the suggestion in How to trigger a job using a rest web service? and now it rises my issue: whenever I called the rest service it runs only the afterJob method. I read how to select which spring batch job to run based on application argument - spring boot java config（与我的问题有一定的相似性）和优秀的博客post指出了它，但我仍然卡住了。我想在 rest 服务之后调用 "public ItemReader reader()"，我希望遵循与通过 main() 启动应用程序时相同的流程。我的意思是，和springboot部署时一样的流程。我想我的困惑在于 @EnableBatchProcessing 或 JobExecutionListenerSupport 但我真的坚持下去。以下是最重要的片段。

控制器

@Autowired
JobLauncher jobLauncher;

@Autowired
Job job;

@RequestMapping("/runit")
public void handle() throws Exception{
       JobParameters jobParameters =
                       new JobParametersBuilder()
                       .addLong("time",System.currentTimeMillis()).toJobParameters();
        jobLauncher.run(job, jobParameters);
}

监听器

@Component
public class JobCompletionNotificationListener extends   
    JobExecutionListenerSupport {

    @Override
    public void afterJob(JobExecution jobExecution) {
        if(jobExecution.getStatus() == BatchStatus.COMPLETED) {

批量配置

@Configuration
@EnableBatchProcessing
public class BatchConfiguration {
    // tag::readerwriterprocessor[]
    @Bean
    public ItemReader<Person> reader() {
        FlatFileItemReader<Person> reader = new FlatFileItemReader<Person>();
        reader.setResource(new ClassPathResource("sample-data.csv"));
        reader.setLineMapper(new DefaultLineMapper<Person>() {{
            setLineTokenizer(new DelimitedLineTokenizer() {{
                setNames(new String[] { "firstName", "lastName" });
            }});

            setFieldSetMapper(new BeanWrapperFieldSetMapper<Person>() {{
                setTargetType(Person.class);
            }});
        }});

        return reader;
    }

    @Bean
    public ItemProcessor<Person, Person> processor() {
        return new PersonItemProcessor();
    }

    @Bean
    public ItemWriter<Person> writer(DataSource dataSource) {
        JdbcBatchItemWriter<Person> writer = new JdbcBatchItemWriter<Person>();
        writer.setItemSqlParameterSourceProvider(new BeanPropertyItemSqlParameterSourceProvider<Person>());

        writer.setSql("INSERT INTO people (first_name, last_name) VALUES (:firstName, :lastName)");

        writer.setDataSource(dataSource);
        return writer;
    }

    @Bean
    public Job importUserJob(JobBuilderFactory jobs, Step s1, JobExecutionListener listener) {
        return jobs.get("importUserJob")
                .incrementer(new RunIdIncrementer())
                .listener(listener)
                .flow(s1)
                .end()
                .build();
    }

    @Bean
    public Step step1(StepBuilderFactory stepBuilderFactory, ItemReader<Person> reader,
            ItemWriter<Person> writer, ItemProcessor<Person, Person> processor) {
        return stepBuilderFactory.get("step1")
                .<Person, Person> chunk(10)
                .reader(reader)
                .processor(processor)
                .writer(writer)
                .build();
    }

application.properties

application.properties
# SPRING BATCH (BatchDatabaseInitializer)
spring.batch.job.enabled=false
spring.batch.initializer.enabled=false

Answer 1

在深入讨论这个问题之后，真正的 "issue" 是 ItemReader 被创建一次，而不是每次 REST 调用一次（也就是每次执行作业一次）。要解决此问题，请将 ItemReader 步骤限定范围。这将允许您获得每个运行的 reader 的新实例，这也使您能够根据作业参数注入文件名。

从代码的角度，改变这个：

@Bean
public ItemReader<Person> reader() {

对此：

@Bean
@StepScope
public FlatFileItemReader<Person> reader() {

return 类型更改的原因是 Spring Batch 会自动为您注册 ItemStreams。但是，当使用 @StepScope 时，我们只会看到您定义的 return。在这种情况下，ItemReader 不会 extend/implement ItemStream 因此我们不知道您正在 return 进行我们应该自动注册的内容。通过 returning FlatFileItemReader 我们可以看到所有 interfaces/etc 并且可以为您应用 "magic"。

如何从休息服务开始批处理。 afterJob 运行但 EnableBatchProcessing 仅在部署后运行

How start the batch from rest service. The afterJob runs but EnableBatchProcessing runs only after deployed

spring

spring-mvc

spring-batch

spring-boot