How to use

abortTransaction

method

in

org.apache.asterix.metadata.api.IMetadataManager

/**
 * Abort the ongoing metadata transaction logging the error cause
 *
 * @param rootE
 * @param parentE
 * @param mdTxnCtx
 */
public static void abort(Exception rootE, Exception parentE, MetadataTransactionContext mdTxnCtx) {
  boolean interrupted = Thread.interrupted();
  try {
    if (IS_DEBUG_MODE) {
      LOGGER.log(Level.ERROR, rootE.getMessage(), rootE);
    }
    if (mdTxnCtx != null) {
      MetadataManager.INSTANCE.abortTransaction(mdTxnCtx);
    }
  } catch (Exception e2) {
    parentE.addSuppressed(e2);
    throw new IllegalStateException(rootE);
  } finally {
    if (interrupted) {
      Thread.currentThread().interrupt();
    }
  }
}

private List<Dataset> getAllDatasetsForRebalance(String dataverseName) throws Exception {
  List<Dataset> datasets;
  MetadataTransactionContext mdTxnCtx = MetadataManager.INSTANCE.beginTransaction();
  try {
    datasets = getDatasetsInDataverseForRebalance(dataverseName, mdTxnCtx);
    MetadataManager.INSTANCE.commitTransaction(mdTxnCtx);
  } catch (Exception e) {
    MetadataManager.INSTANCE.abortTransaction(mdTxnCtx);
    throw e;
  }
  return datasets;
}

private List<Dataset> getAllDatasetsForRebalance() throws Exception {
  List<Dataset> datasets = new ArrayList<>();
  MetadataTransactionContext mdTxnCtx = MetadataManager.INSTANCE.beginTransaction();
  try {
    List<Dataverse> dataverses = MetadataManager.INSTANCE.getDataverses(mdTxnCtx);
    for (Dataverse dv : dataverses) {
      datasets.addAll(getDatasetsInDataverseForRebalance(dv.getDataverseName(), mdTxnCtx));
    }
    MetadataManager.INSTANCE.commitTransaction(mdTxnCtx);
  } catch (Exception e) {
    MetadataManager.INSTANCE.abortTransaction(mdTxnCtx);
    throw e;
  }
  return datasets;
}

/**
 * Perform recovery of DDL operations metadata records
 */
public static void startDDLRecovery() throws AlgebricksException {
  // #. clean up any record which has pendingAdd/DelOp flag
  // as traversing all records from DATAVERSE_DATASET to DATASET_DATASET, and then
  // to INDEX_DATASET.
  MetadataTransactionContext mdTxnCtx = null;
  LOGGER.info("Starting DDL recovery ...");
  try {
    mdTxnCtx = MetadataManager.INSTANCE.beginTransaction();
    List<Dataverse> dataverses = MetadataManager.INSTANCE.getDataverses(mdTxnCtx);
    for (Dataverse dataverse : dataverses) {
      recoverDataverse(mdTxnCtx, dataverse);
    }
    MetadataManager.INSTANCE.commitTransaction(mdTxnCtx);
    LOGGER.info("Completed DDL recovery.");
  } catch (Exception e) {
    try {
      LOGGER.error("Failure during DDL recovery", e);
      MetadataManager.INSTANCE.abortTransaction(mdTxnCtx);
    } catch (Exception e2) {
      e.addSuppressed(e2);
    }
    throw MetadataException.create(e);
  }
}

if (ctx != null) {
  try {
    MetadataManager.INSTANCE.abortTransaction(ctx);
  } catch (ACIDException | RemoteException e2) {
    e.addSuppressed(e2);

  LOGGER.log(Level.ERROR, "Exception in installing library " + libraryName, e);
MetadataManager.INSTANCE.abortTransaction(mdTxnCtx);

    LOGGER.log(Level.ERROR, "Failure during metadata bootstrap", e);
  MetadataManager.INSTANCE.abortTransaction(mdTxnCtx);
} catch (Exception e2) {
  e.addSuppressed(e2);

  MetadataManager.INSTANCE.commitTransaction(mdTxnCtx);
} catch (Exception e) {
  MetadataManager.INSTANCE.abortTransaction(mdTxnCtx);
  throw new AsterixException(e);

@Test
public void abortMetadataTxn() throws Exception {
  ICcApplicationContext appCtx =
      (ICcApplicationContext) integrationUtil.getClusterControllerService().getApplicationContext();
  final MetadataProvider metadataProvider = new MetadataProvider(appCtx, null);
  final MetadataTransactionContext mdTxn = MetadataManager.INSTANCE.beginTransaction();
  metadataProvider.setMetadataTxnContext(mdTxn);
  final String nodeGroupName = "ng";
  try {
    final List<String> ngNodes = Arrays.asList("asterix_nc1");
    MetadataManager.INSTANCE.addNodegroup(mdTxn, new NodeGroup(nodeGroupName, ngNodes));
    MetadataManager.INSTANCE.abortTransaction(mdTxn);
  } finally {
    metadataProvider.getLocks().unlock();
  }
  // ensure that the node group was not added
  final MetadataTransactionContext readMdTxn = MetadataManager.INSTANCE.beginTransaction();
  try {
    final NodeGroup nodegroup = MetadataManager.INSTANCE.getNodegroup(readMdTxn, nodeGroupName);
    if (nodegroup != null) {
      throw new AssertionError("nodegroup was found after metadata txn was aborted");
    }
  } finally {
    MetadataManager.INSTANCE.commitTransaction(readMdTxn);
  }
}

      sourceDataset.getRebalanceCount() + 1, rebalanceToNodes, metadataProvider);
  MetadataManager.INSTANCE.abortTransaction(rebalanceTxn);
} finally {
  metadataProvider.getLocks().unlock();

  private void addDataset(ICcApplicationContext appCtx, Dataset source, int datasetPostfix, boolean abort)
      throws Exception {
    Dataset dataset = new Dataset(source.getDataverseName(), "ds_" + datasetPostfix, source.getDataverseName(),
        source.getDatasetType().name(), source.getNodeGroupName(), NoMergePolicyFactory.NAME, null,
        source.getDatasetDetails(), source.getHints(), DatasetConfig.DatasetType.INTERNAL, datasetPostfix, 0);
    MetadataProvider metadataProvider = new MetadataProvider(appCtx, null);
    final MetadataTransactionContext writeTxn = MetadataManager.INSTANCE.beginTransaction();
    metadataProvider.setMetadataTxnContext(writeTxn);
    try {
      MetadataManager.INSTANCE.addDataset(writeTxn, dataset);
      if (abort) {
        MetadataManager.INSTANCE.abortTransaction(writeTxn);
      } else {
        MetadataManager.INSTANCE.commitTransaction(writeTxn);
      }
    } finally {
      metadataProvider.getLocks().unlock();
    }
  }
}