Examples with Scanner com.scalar.db.api.Scanner used on opensource projects

Example 6 with Scanner

use of com.scalar.db.api.Scanner in project scalardb by scalar-labs.

the class Dynamo method get.

@Override
@Nonnull
public Optional<Result> get(Get get) throws ExecutionException {
    get = copyAndSetTargetToIfNot(get);
    operationChecker.check(get);
    Scanner scanner = null;
    try {
        scanner = selectStatementHandler.handle(get);
        Optional<Result> ret = scanner.one();
        if (scanner.one().isPresent()) {
            throw new IllegalArgumentException("please use scan() for non-exact match selection");
        }
        return ret;
    } finally {
        if (scanner != null) {
            try {
                scanner.close();
            } catch (IOException e) {
                LOGGER.warn("failed to close the scanner", e);
            }
        }
    }
}

Example 7 with Scanner

use of com.scalar.db.api.Scanner in project scalardb by scalar-labs.

the class CrudHandler method scan.

public List<Result> scan(Scan scan) throws CrudException {
    List<String> originalProjections = new ArrayList<>(scan.getProjections());
    List<Result> results = new ArrayList<>();
    Optional<List<Snapshot.Key>> keysInSnapshot = snapshot.get(scan);
    if (keysInSnapshot.isPresent()) {
        for (Snapshot.Key key : keysInSnapshot.get()) {
            snapshot.get(key).ifPresent(results::add);
        }
        return createScanResults(scan, originalProjections, results);
    }
    List<Snapshot.Key> keys = new ArrayList<>();
    Scanner scanner = null;
    try {
        scanner = getFromStorage(scan);
        for (Result r : scanner) {
            TransactionResult result = new TransactionResult(r);
            if (!result.isCommitted()) {
                throw new UncommittedRecordException(result, "the record needs recovery");
            }
            Snapshot.Key key = new Snapshot.Key(scan, r);
            if (!snapshot.containsKeyInReadSet(key)) {
                snapshot.put(key, Optional.of(result));
            }
            keys.add(key);
            snapshot.get(key).ifPresent(results::add);
        }
    } finally {
        if (scanner != null) {
            try {
                scanner.close();
            } catch (IOException e) {
                LOGGER.warn("failed to close the scanner", e);
            }
        }
    }
    snapshot.put(scan, keys);
    return createScanResults(scan, originalProjections, results);
}

Example 8 with Scanner

use of com.scalar.db.api.Scanner in project scalardb by scalar-labs.

the class SelectStatementHandlerTest method handle_GetOperationNoItemReturned_ShouldReturnEmptyScanner.

@Test
public void handle_GetOperationNoItemReturned_ShouldReturnEmptyScanner() throws Exception {
    // Arrange
    when(client.getItem(any(GetItemRequest.class))).thenReturn(getResponse);
    when(getResponse.hasItem()).thenReturn(false);
    Get get = prepareGet();
    // Act Assert
    List<Result> actual;
    try (Scanner scanner = handler.handle(get)) {
        actual = scanner.all();
    }
    // Assert
    assertThat(actual).isEmpty();
}

Example 9 with Scanner

use of com.scalar.db.api.Scanner in project scalardb by scalar-labs.

the class JdbcDatabaseTest method whenScanOperationExecutedAndScannerClosed_shouldCallJdbcService.

@Test
public void whenScanOperationExecutedAndScannerClosed_shouldCallJdbcService() throws Exception {
    // Arrange
    when(jdbcService.getScanner(any(), any())).thenReturn(new ScannerImpl(resultInterpreter, connection, preparedStatement, resultSet));
    // Act
    Scan scan = new Scan(new Key("p1", "val")).forNamespace(NAMESPACE).forTable(TABLE);
    Scanner scanner = jdbcDatabase.scan(scan);
    scanner.close();
    // Assert
    verify(jdbcService).getScanner(any(), any());
    verify(connection).close();
}

Example 10 with Scanner

use of com.scalar.db.api.Scanner in project scalardb by scalar-labs.

the class SnapshotTest method toSerializableWithExtraRead_ScanSetUpdated_ShouldProcessWithoutExceptions.

@Test
public void toSerializableWithExtraRead_ScanSetUpdated_ShouldProcessWithoutExceptions() throws ExecutionException {
    // Arrange
    snapshot = prepareSnapshot(Isolation.SERIALIZABLE, SerializableStrategy.EXTRA_READ);
    Scan scan = prepareScan();
    Put put = preparePut();
    TransactionResult txResult = prepareResult(ANY_ID);
    Snapshot.Key key = new Snapshot.Key(scan, txResult);
    snapshot.put(key, Optional.of(txResult));
    snapshot.put(scan, Collections.singletonList(key));
    snapshot.put(new Snapshot.Key(put), put);
    DistributedStorage storage = mock(DistributedStorage.class);
    TransactionResult changedTxResult = prepareResult(ANY_ID + "x");
    Scanner scanner = mock(Scanner.class);
    when(scanner.iterator()).thenReturn(Collections.singletonList((Result) changedTxResult).iterator());
    Scan scanWithProjections = prepareScan().withProjections(Arrays.asList(Attribute.ID, Attribute.VERSION, ANY_NAME_1, ANY_NAME_2));
    when(storage.scan(scanWithProjections)).thenReturn(scanner);
    // Act Assert
    assertThatThrownBy(() -> snapshot.toSerializableWithExtraRead(storage)).isInstanceOf(CommitConflictException.class);
    // Assert
    verify(storage).scan(scanWithProjections);
}