为什么新的线程在事务Spring JUnit测试中看不到主线程准备的测试数据？

Question

我用Spring-boot-test写了一个Junit测试,在一个测试方法中,我首先准备了一些应该保存到MySQL DB的测试数据,然后我调用了目标方法,应该在100个子线程中进行测试来测试目标方法是否在并发中运行良好.此测试方法如下所示:

public class SysCodeRuleServiceImplTest extends BaseServiceTest {

    @Autowired
    private SysCodeRuleService sysCodeRuleService;

    @Autowired
    private SysCodeRuleDtlService sysCodeRuleDtlService;

    private final String codeRuleNo = "sdkfjks443";

        @Test
    public void testCreateSheetIdWithoutUniformedSerial_2() throws InterruptedException {
                //------ prepare test data start-----------
        SysCodeRule sysCodeRule = new SysCodeRule();
        sysCodeRule.setCodeRuleNo(codeRuleNo);
        sysCodeRule.setIfDateCode(1);
        sysCodeRule.setPadChar("0");
        sysCodeRule.setSerialDigits(6);
        sysCodeRule.setResetMode(1);
        sysCodeRule.setIfUniteSerial(0);
        sysCodeRule.setIfCache(0);
        sysCodeRule.setConstValue("PETREL");
        sysCodeRule.setStatus(1);
        sysCodeRule.setName(codeRuleNo);
        sysCodeRule.setCurSerialNo("0");
        sysCodeRule.setCurSerialDate(new Date());
        sysCodeRule.setCreateTime(new Date());
        sysCodeRule.setCreator("??");
        sysCodeRule.setDateCutBeginPosition(3);
        sysCodeRule.setDateCutEndPosition(8);
        boolean insertSysCodeRuleSucc = sysCodeRuleService.insert(sysCodeRule);
        assertThat(TestMessageConstants.PREPARE_TEST_DATA_FAILED, insertSysCodeRuleSucc);
        assertThat("", sysCodeRule.getId(), notNullValue());

        SysCodeRuleDtl sysCodeRuleDtl1 = new SysCodeRuleDtl();
        sysCodeRuleDtl1.setSysCodeId(sysCodeRule.getId() + "");
        sysCodeRuleDtl1.setOrderNo(1);
        sysCodeRuleDtl1.setFieldValue("locno");
        sysCodeRuleDtl1.setCutEndPosition(0);
        sysCodeRuleDtl1.setCutBeginPosition(0);
        sysCodeRuleDtl1.setCreateTime(new Date());
        sysCodeRuleDtl1.setCreator("??");
        boolean insertDtl1Succ = sysCodeRuleDtlService.insert(sysCodeRuleDtl1);
        assertThat("", insertDtl1Succ);

        SysCodeRuleDtl sysCodeRuleDtl2 = new SysCodeRuleDtl();
        sysCodeRuleDtl2.setSysCodeId(sysCodeRule.getId() + "");
        sysCodeRuleDtl2.setOrderNo(2);
        sysCodeRuleDtl2.setFieldValue("fieldName1");
        sysCodeRuleDtl2.setCutBeginPosition(1);
        sysCodeRuleDtl2.setCutEndPosition(3);
        sysCodeRuleDtl2.setCreateTime(new Date());
        sysCodeRuleDtl2.setCreator("??");
        boolean insertDtl1Succ2 = sysCodeRuleDtlService.insert(sysCodeRuleDtl2);
        assertThat("", insertDtl1Succ2);
                //------prepare test data end------------------------

                //startLatch used to make sure all task threads start after 
                //prepared test data done
        CountDownLatch startLatch = new CountDownLatch(1);
                //parameters needed by the target method
        Map<String, String> fieldValueMap = new HashMap<>(2);
        fieldValueMap.put("locno", "cangku1");
        fieldValueMap.put("fieldName1", "ABCDEFGH");
                //doneLatch used to make sure all task threads done before the
                //the transaction which started in main thread roll back
        CountDownLatch doneLatch = new CountDownLatch(100);
        for(int i = 0; i < 100; i++) {
            new Thread(() -> {
                try {
                    startLatch.await();
                //this is the target method which i want to test
                    String result = sysCodeRuleService.createSheetIdWithoutUniformedSerial(codeRuleNo, JsonUtils.writeValueAsString(fieldValueMap));
                    if(CommonUtil.isNotNull(result)) {
                        logger.debug(">>>>>>>>>>>>>" + result);
                    }
                } catch(InterruptedException e) {
                    e.printStackTrace();
                } finally {
                    doneLatch.countDown();
                }
            }).start();
        }

                //guarantee the test data truly saved before all task treads 
                //start
        EntityWrapper<SysCodeRule> ew = new EntityWrapper<>();
        ew.eq("code_rule_no", codeRuleNo);
        SysCodeRule codeRule = sysCodeRuleService.selectOne(ew);
        if(codeRule != null) {
            startLatch.countDown();
        }
                //main thread keep waiting until all task threads done their 
                //work
        doneLatch.await();
    }

该BaseServiceTest如下所示:

@RunWith(SpringRunner.class)
@SpringBootTest(classes = TestApplication.class)
@Transactional
@Rollback
public class BaseServiceTest {
    protected  Logger logger = LoggerFactory.getLogger(BaseServiceTest.class);
}

目标方法的签名如下所示:

public synchronized String createSheetIdWithoutUniformedSerial(String codeRuleNo, String fieldValuesJson)

在目标方法中,它查询由"准备测试数据"代码块保存的数据,然后执行一些业务逻辑代码,然后返回结果.顺便说一句,在"业务服务层"中写入的目标方法具有由Spring AOP管理的事务,并且事务配置文件如下所示:

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd">

    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="doReweight" propagation="REQUIRES_NEW"/>
            <tx:method name="doClear*" propagation="REQUIRES_NEW"/>
            <tx:method name="doSend*" propagation="REQUIRES_NEW"/>
            <tx:method name="doBatchSave*" propagation="REQUIRES_NEW"/>

            <tx:method name="get*" propagation="REQUIRED" read-only="true"/>
            <tx:method name="count*" propagation="REQUIRED" read-only="true"/>
            <tx:method name="find*" propagation="REQUIRED" read-only="true"/>
            <tx:method name="list*" propagation="REQUIRED" read-only="true"/>
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

    <aop:config expose-proxy="true" proxy-target-class="true">
        <aop:pointcut id="txPointcut"
                      expression="execution(* com.xxx..service..*+.*(..))"/>
        <aop:advisor id="txAdvisor" advice-ref="txAdvice"
                     pointcut-ref="txPointcut"/>
    </aop:config>
</beans>

我的预期结果是同步目标方法运行良好

但!在每个子任务线程中,目标方法无法查询在主线程中准备好的准备好的测试数据!

所以,我很困惑,无法弄清楚出了什么问题？需要一些帮助或提示,我真的很感谢你们的帮助,提前谢谢!

ps:spring-boot verison是:1.5.10.RELEASE,Juite版本是:4.12

Answer 1

通过SysCodeRuleService在测试管理事务中插入测试数据与数据库的初始交互,该事务未提交给数据库.

然后createSheetIdWithoutUniformedSerial()在你的调用中SysCodeRuleService执行新线程; 但是,Spring不会将事务传播到新生成的线程.因此,createSheetIdWithoutUniformedSerial()在不同的线程中调用运行,这些线程无法在挂起的测试管理事务中看到未提交的测试数据.

为了允许createSheetIdWithoutUniformedSerial()在新线程中查看数据库中的此类测试数据,您必须在生成任何新线程之前将测试数据提交到数据库.

有几种方法可以实现这一目标.

如果您正在寻找一种非常低级的技术,可以使用SpringTransactionTemplate以编程方式提交数据库.这应该适用于测试管理的事务(即,通过@Transactional测试类或测试方法).

如果要执行特定于当前@Test方法的数据库设置,则另一个选项是使用TestTransactionAPI.有关详细信息,请参阅Spring Framework Reference Manual中的Programmatic Transaction Management.

如果要对当前类中的所有测试方法执行相同的数据库设置,可以引入@BeforeTransaction将测试数据插入数据库的@AfterTransaction方法以及从数据库中删除测试数据的方法.请参阅在事务之外运行代码.

如果您愿意或有兴趣将测试数据设置移动到SQL插入语句(可能在外部文件中),则可以使用Spring的@Sql支持.

作为旁注,您可以安全地删除@Rollback声明,因为您使用默认语义有效地覆盖了默认语义.