聊聊sharding-jdbc的ShardingTransactionManager
阿新 • • 發佈:2019-08-12
序
本文主要研究一下sharding-jdbc的ShardingTransactionManager
ShardingTransactionManager
incubator-shardingsphere-4.0.0-RC1/sharding-transaction/sharding-transaction-core/src/main/java/org/apache/shardingsphere/transaction/spi/ShardingTransactionManager.java
public interface ShardingTransactionManager extends AutoCloseable { /** * Initialize sharding transaction manager. * * @param databaseType database type * @param resourceDataSources resource data sources */ void init(DatabaseType databaseType, Collection<ResourceDataSource> resourceDataSources); /** * Get transaction type. * * @return transaction type */ TransactionType getTransactionType(); /** * Judge is in transaction or not. * * @return in transaction or not */ boolean isInTransaction(); /** * Get transactional connection. * * @param dataSourceName data source name * @return connection * @throws SQLException SQL exception */ Connection getConnection(String dataSourceName) throws SQLException; /** * Begin transaction. */ void begin(); /** * Commit transaction. */ void commit(); /** * Rollback transaction. */ void rollback(); }
- ShardingTransactionManager繼承了AutoCloseable介面,它定義了init、getTransactionType、isInTransaction、getConnection、begin、commit、rollback方法
XAShardingTransactionManager
incubator-shardingsphere-4.0.0-RC1/sharding-transaction/sharding-transaction-2pc/sharding-transaction-xa/sharding-transaction-xa-core/src/main/java/org/apache/shardingsphere/transaction/xa/XAShardingTransactionManager.java
public final class XAShardingTransactionManager implements ShardingTransactionManager { private final Map<String, SingleXADataSource> singleXADataSourceMap = new HashMap<>(); private final XATransactionManager xaTransactionManager = XATransactionManagerLoader.getInstance().getTransactionManager(); private ThreadLocal<List<String>> enlistedXAResource = new ThreadLocal<List<String>>() { @Override public List<String> initialValue() { return new LinkedList<>(); } }; @Override public void init(final DatabaseType databaseType, final Collection<ResourceDataSource> resourceDataSources) { for (ResourceDataSource each : resourceDataSources) { DataSource dataSource = each.getDataSource(); if (dataSource instanceof AtomikosDataSourceBean) { continue; } SingleXADataSource singleXADataSource = new SingleXADataSource(databaseType, each.getUniqueResourceName(), dataSource); singleXADataSourceMap.put(each.getOriginalName(), singleXADataSource); xaTransactionManager.registerRecoveryResource(each.getUniqueResourceName(), singleXADataSource.getXaDataSource()); } xaTransactionManager.init(); } @Override public TransactionType getTransactionType() { return TransactionType.XA; } @SneakyThrows @Override public boolean isInTransaction() { return Status.STATUS_NO_TRANSACTION != xaTransactionManager.getTransactionManager().getStatus(); } @SneakyThrows @Override public Connection getConnection(final String dataSourceName) { SingleXAConnection singleXAConnection = singleXADataSourceMap.get(dataSourceName).getXAConnection(); if (!enlistedXAResource.get().contains(dataSourceName)) { xaTransactionManager.enlistResource(singleXAConnection.getXAResource()); enlistedXAResource.get().add(dataSourceName); } return singleXAConnection.getConnection(); } @SneakyThrows @Override public void begin() { xaTransactionManager.getTransactionManager().begin(); } @SneakyThrows @Override public void commit() { try { xaTransactionManager.getTransactionManager().commit(); } finally { enlistedXAResource.remove(); } } @SneakyThrows @Override public void rollback() { try { xaTransactionManager.getTransactionManager().rollback(); } finally { enlistedXAResource.remove(); } } @Override public void close() throws Exception { for (SingleXADataSource each : singleXADataSourceMap.values()) { xaTransactionManager.removeRecoveryResource(each.getResourceName(), each.getXaDataSource()); } singleXADataSourceMap.clear(); xaTransactionManager.close(); enlistedXAResource = null; } }
- XAShardingTransactionManager實現了ShardingTransactionManager介面,它擁有singleXADataSourceMap、xaTransactionManager、enlistedXAResource三個屬性,其init方法對這三個屬性進行了初始化
- getTransactionType方法返回的是TransactionType.XA;isInTransaction方法則依據xaTransactionManager.getTransactionManager().getStatus()來判斷;getConnection方法從singleXADataSourceMap取出singleXAConnection,然後執行其getConnection方法
- begin方法執行的是xaTransactionManager.getTransactionManager().begin();commit方法則呼叫了xaTransactionManager.getTransactionManager().commit(),其會在finally中執行enlistedXAResource.remove();rollback方法呼叫了xaTransactionManager.getTransactionManager().rollback(),其也在finally中執行enlistedXAResource.remove();close方法則執行xaTransactionManager.removeRecoveryResource、singleXADataSourceMap.clear()、xaTransactionManager.close()
XAShardingTransactionManagerTest
incubator-shardingsphere-4.0.0-RC1/sharding-transaction/sharding-transaction-2pc/sharding-transaction-xa/sharding-transaction-xa-core/src/test/java/org/apache/shardingsphere/transaction/xa/XAShardingTransactionManagerTest.java
@RunWith(MockitoJUnitRunner.class)
public final class XAShardingTransactionManagerTest {
private XAShardingTransactionManager xaShardingTransactionManager = new XAShardingTransactionManager();
@Mock
private XATransactionManager xaTransactionManager;
@Mock
private TransactionManager transactionManager;
@Before
public void setUp() {
when(xaTransactionManager.getTransactionManager()).thenReturn(transactionManager);
ReflectiveUtil.setProperty(xaShardingTransactionManager, "xaTransactionManager", xaTransactionManager);
}
@Test
public void assertGetTransactionType() {
assertThat(xaShardingTransactionManager.getTransactionType(), is(TransactionType.XA));
}
@Test
public void assertRegisterXATransactionalDataSources() {
Collection<ResourceDataSource> resourceDataSources = createResourceDataSources(DruidXADataSource.class, DatabaseType.MySQL);
xaShardingTransactionManager.init(DatabaseType.MySQL, resourceDataSources);
for (ResourceDataSource each : resourceDataSources) {
verify(xaTransactionManager).registerRecoveryResource(each.getUniqueResourceName(), (XADataSource) each.getDataSource());
}
}
@Test
public void assertRegisterAtomikosDataSourceBeans() {
xaShardingTransactionManager.init(DatabaseType.MySQL, createAtomikosDataSourceBeanResource());
verify(xaTransactionManager, times(0)).registerRecoveryResource(anyString(), any(XADataSource.class));
}
@Test
public void assertRegisterNoneXATransactionalDAtaSources() {
Collection<ResourceDataSource> resourceDataSources = createResourceDataSources(HikariDataSource.class, DatabaseType.MySQL);
xaShardingTransactionManager.init(DatabaseType.MySQL, resourceDataSources);
Map<String, SingleXADataSource> cachedXADatasourceMap = getCachedSingleXADataSourceMap();
assertThat(cachedXADatasourceMap.size(), is(2));
}
@Test
public void assertIsInTransaction() throws SystemException {
when(transactionManager.getStatus()).thenReturn(Status.STATUS_ACTIVE);
assertTrue(xaShardingTransactionManager.isInTransaction());
}
@Test
public void assertIsNotInTransaction() throws SystemException {
when(transactionManager.getStatus()).thenReturn(Status.STATUS_NO_TRANSACTION);
assertFalse(xaShardingTransactionManager.isInTransaction());
}
@Test
public void assertGetConnection() {
setCachedSingleXADataSourceMap("ds1");
Connection actual = xaShardingTransactionManager.getConnection("ds1");
assertThat(actual, instanceOf(Connection.class));
verify(xaTransactionManager).enlistResource(any(SingleXAResource.class));
}
@Test
public void assertGetConnectionWithoutEnlist() {
setCachedSingleXADataSourceMap("ds1");
Connection actual = xaShardingTransactionManager.getConnection("ds1");
assertThat(actual, instanceOf(Connection.class));
xaShardingTransactionManager.getConnection("ds1");
assertThat(actual, instanceOf(Connection.class));
verify(xaTransactionManager).enlistResource(any(SingleXAResource.class));
}
@Test
public void assertClose() throws Exception {
setCachedSingleXADataSourceMap("ds1");
xaShardingTransactionManager.close();
Map<String, SingleXADataSource> cachedSingleXADataSourceMap = getCachedSingleXADataSourceMap();
verify(xaTransactionManager).removeRecoveryResource(anyString(), any(XADataSource.class));
assertThat(cachedSingleXADataSourceMap.size(), is(0));
}
@SneakyThrows
@SuppressWarnings("unchecked")
private Map<String, SingleXADataSource> getCachedSingleXADataSourceMap() {
Field field = xaShardingTransactionManager.getClass().getDeclaredField("singleXADataSourceMap");
field.setAccessible(true);
return (Map<String, SingleXADataSource>) field.get(xaShardingTransactionManager);
}
@SneakyThrows
private void setCachedSingleXADataSourceMap(final String datasourceName) {
Field field = xaShardingTransactionManager.getClass().getDeclaredField("singleXADataSourceMap");
field.setAccessible(true);
field.set(xaShardingTransactionManager, createMockSingleXADataSourceMap(datasourceName));
}
@SneakyThrows
private Map<String, SingleXADataSource> createMockSingleXADataSourceMap(final String datasourceName) {
SingleXADataSource singleXADataSource = mock(SingleXADataSource.class);
SingleXAConnection singleXAConnection = mock(SingleXAConnection.class);
XADataSource xaDataSource = mock(XADataSource.class);
SingleXAResource singleXAResource = mock(SingleXAResource.class);
Connection connection = mock(Connection.class);
when(singleXAConnection.getConnection()).thenReturn(connection);
when(singleXAConnection.getXAResource()).thenReturn(singleXAResource);
when(singleXADataSource.getXAConnection()).thenReturn(singleXAConnection);
when(singleXADataSource.getResourceName()).thenReturn(datasourceName);
when(singleXADataSource.getXaDataSource()).thenReturn(xaDataSource);
Map<String, SingleXADataSource> result = new HashMap<>();
result.put(datasourceName, singleXADataSource);
return result;
}
private Collection<ResourceDataSource> createResourceDataSources(final Class<? extends DataSource> dataSourceClass, final DatabaseType databaseType) {
List<ResourceDataSource> result = new LinkedList<>();
result.add(new ResourceDataSource("ds1", DataSourceUtils.build(dataSourceClass, databaseType, "demo_ds_1")));
result.add(new ResourceDataSource("ds2", DataSourceUtils.build(dataSourceClass, databaseType, "demo_ds_2")));
return result;
}
private Collection<ResourceDataSource> createAtomikosDataSourceBeanResource() {
List<ResourceDataSource> result = new LinkedList<>();
result.add(new ResourceDataSource("ds1", new AtomikosDataSourceBean()));
result.add(new ResourceDataSource("ds2", new AtomikosDataSourceBean()));
return result;
}
}
- 這裡mock了xaTransactionManager、transactionManager
小結
- XAShardingTransactionManager實現了ShardingTransactionManager介面,它擁有singleXADataSourceMap、xaTransactionManager、enlistedXAResource三個屬性,其init方法對這三個屬性進行了初始化
- getTransactionType方法返回的是TransactionType.XA;isInTransaction方法則依據xaTransactionManager.getTransactionManager().getStatus()來判斷;getConnection方法從singleXADataSourceMap取出singleXAConnection,然後執行其getConnection方法
- begin方法執行的是xaTransactionManager.getTransactionManager().begin();commit方法則呼叫了xaTransactionManager.getTransactionManager().commit(),其會在finally中執行enlistedXAResource.remove();rollback方法呼叫了xaTransactionManager.getTransactionManager().rollback(),其也在finally中執行enlistedXAResource.remove();close方法則執行xaTransactionManager.removeRecoveryResource、singleXADataSourceMap.clear()、xaTransactionManager.close()