/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.facebook.presto.example;
import com.facebook.presto.spi.ConnectorSplitManager;
import com.facebook.presto.spi.FixedSplitSource;
import com.facebook.presto.spi.Partition;
import com.facebook.presto.spi.PartitionResult;
import com.facebook.presto.spi.Split;
import com.facebook.presto.spi.SplitSource;
import com.facebook.presto.spi.TableHandle;
import com.facebook.presto.spi.TupleDomain;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Lists;
import javax.inject.Inject;
import java.net.URI;
import java.util.Collections;
import java.util.List;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
public class ExampleSplitManager
implements ConnectorSplitManager
{
private final String connectorId;
private final ExampleClient exampleClient;
@Inject
public ExampleSplitManager(ExampleConnectorId connectorId, ExampleClient exampleClient)
{
this.connectorId = checkNotNull(connectorId, "connectorId is null").toString();
this.exampleClient = checkNotNull(exampleClient, "client is null");
}
@Override
public String getConnectorId()
{
return connectorId;
}
@Override
public boolean canHandle(TableHandle tableHandle)
{
return tableHandle instanceof ExampleTableHandle && ((ExampleTableHandle) tableHandle).getConnectorId().equals(connectorId);
}
@Override
public PartitionResult getPartitions(TableHandle tableHandle, TupleDomain tupleDomain)
{
checkArgument(tableHandle instanceof ExampleTableHandle, "tableHandle is not an instance of ExampleTableHandle");
ExampleTableHandle exampleTableHandle = (ExampleTableHandle) tableHandle;
// example connector has only one partition
List<Partition> partitions = ImmutableList.<Partition>of(new ExamplePartition(exampleTableHandle.getSchemaName(), exampleTableHandle.getTableName()));
// example connector does not do any additional processing/filtering with the TupleDomain, so just return the whole TupleDomain
return new PartitionResult(partitions, tupleDomain);
}
@Override
public SplitSource getPartitionSplits(TableHandle tableHandle, List<Partition> partitions)
{
checkNotNull(partitions, "partitions is null");
checkArgument(partitions.size() == 1, "Expected one partition but got %s", partitions.size());
Partition partition = partitions.get(0);
checkArgument(partition instanceof ExamplePartition, "partition is not an instance of ExamplePartition");
ExamplePartition examplePartition = (ExamplePartition) partition;
ExampleTableHandle exampleTableHandle = (ExampleTableHandle) tableHandle;
ExampleTable table = exampleClient.getTable(exampleTableHandle.getSchemaName(), exampleTableHandle.getTableName());
// this can happen if table is removed during a query
checkState(table != null, "Table %s.%s no longer exists", exampleTableHandle.getSchemaName(), exampleTableHandle.getTableName());
List<Split> splits = Lists.newArrayList();
for (URI uri : table.getSources()) {
splits.add(new ExampleSplit(connectorId, examplePartition.getSchemaName(), examplePartition.getTableName(), uri));
}
Collections.shuffle(splits);
return new FixedSplitSource(connectorId, splits);
}
}