java - Spring在不重新启动应用程序的情况下找不到创建的表

问题描述

我有一个相当具体的场景，我遇到了问题：

我有一个骆驼路线，它试图从任意数量的数据源中获取数据并将其插入中央数据库。如果目标表在中心数据库中不存在，我会尝试从源数据库中获取 DDL。在中央数据库中创建丢失的表效果很好，但是当下次骆驼路线按计划运行时，它找不到表，即使我可以在我的数据库工具中看到它。如果我只是重新启动 spring boot 实例，它会找到表并且它可以工作。

为了让您更好地了解它是如何工作的，下面是它出错的部分路线：

from("direct:ensureTargetTableExists")
    .routeId("ensureTargetTableExists")
    .doTry()
        .toD(String.format("sql:select * from ${in.header.%s} where false?dataSource=%s&outputHeader=%s", QueryHandler.Properties.TARGET_TABLE, DataSourceHandler.Properties.TARGET_DATASOURCE_NAME, "tableExists"))
        .to("direct:handleResultSet")
    .doCatch(BadSqlGrammarException.class)
        .log("entered catch")
        .log(LoggingLevel.INFO, String.format("Could not find table ${in.header.%s} at %s, will attempt to create it by fetching DDL.", QueryHandler.Properties.TARGET_TABLE, DataSourceHandler.Properties.TARGET_DATASOURCE_NAME))
        .to("direct:fetchTableDdlFromSource")
    .endDoTry();

from("direct:fetchTableDdlFromSource")
    .routeId("fetchTableDdlFromSource")
    .streamCaching()
    .bean(DumpHandler.class, "generateDumpCommand")
    .toD(String.format("ssh:{{sync.dump.ssh.user}}@${in.header.%s}?password={{sync.dump.ssh.password}}", DataSourceHandler.Properties.FETCHED_FROM_HOST))
    .to("direct:applyDdlToTargetDatabase");

from("direct:applyDdlToTargetDatabase")
    .routeId("applyDdlToTargetDatabase")
    .transacted("targetTransactionPolicy")
    .toD(String.format("sql:?dataSource=%s&useMessageBodyForSql=true", DataSourceHandler.Properties.TARGET_DATASOURCE_NAME))
    .bean(FileUtil.class, "saveDdl")
    // Nothing else is called after this, since I want the transaction to be completed and commited
    .log(LoggingLevel.INFO, "Table will be populated next scheduled run.");

我让它运行两次迭代，这就是发生的事情：

entered catch
Could not find table article_flags at target, will attempt to create it by fetching DDL.
Saving DDL to config/sql/ddl/article_flags-20181206_162310.sql
Successfully created table article_flags
Table will be populated next scheduled run.
entered catch
Could not find table article_flags at target, will attempt to create it by fetching DDL.
Failed delivery for (MessageId: ID-overlord-1544109787810-0-12 on ExchangeId: ID-overlord-1544109787810-0-9). Exhausted after delivery attempt: 1 caught: org.springframework.jdbc.BadSqlGrammarException: PreparedStatementCallback; bad SQL grammar []; nested exception is org.postgresql.util.PSQLException: ERROR: relation "article_flags" already exists

我尝试使用在应用程序启动时添加的事务管理器和事务策略来解决此问题，但无济于事。如您所见，我targetTransactionPolicy在上面的骆驼路线中使用了交易策略。

public class ContextConfiguration implements BeanDefinitionRegistryPostProcessor {

    private static final Logger LOG = LoggerFactory.getLogger(ContextConfiguration.class);

    private Map<String, BasicDataSource> datasources;

    public ContextConfiguration(Map<String, BasicDataSource> datasources) {
        this.datasources = datasources;
    }

    @Override
    public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) throws BeansException {
        for (Entry<String, BasicDataSource> source : datasources.entrySet()) {
            LOG.info("Adding datasource {} targeting {} to Spring registry", source.getKey(), source.getValue().getUrl());
            PlatformTransactionManager transactionManager = new DataSourceTransactionManager(source.getValue());
            SpringTransactionPolicy transactionPolicy = new SpringTransactionPolicy(transactionManager);
            registry.registerBeanDefinition(source.getKey() + "TransactionPolicy", BeanDefinitionBuilder.genericBeanDefinition(SpringTransactionPolicy.class, () -> transactionPolicy).getBeanDefinition());
            registry.registerBeanDefinition(source.getKey() + "TransactionManager", BeanDefinitionBuilder.genericBeanDefinition(PlatformTransactionManager.class, () -> transactionManager).getBeanDefinition());
            registry.registerBeanDefinition(source.getKey(), BeanDefinitionBuilder.genericBeanDefinition(BasicDataSource.class, () -> source.getValue()).getBeanDefinition());
        }
    }

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException { }

}

在过去的几天里，我一直在听这件事，我似乎无法克服这个问题。任何帮助或见解将不胜感激。我最好的猜测是它与事务有关，或者我创建事务管理器、策略和数据源的方式。

附加信息：

春季启动 2.1.1
骆驼 2.23.0
底层数据源是 Postgres 10.6

标签： javadatabasespringapache-camel

java - Spring在不重新启动应用程序的情况下找不到创建的表

问题描述

解决方案

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