asterix-external-data/src/main/java/edu/uci/ics/asterix/external/data/operator/FeedIntakeOperatorDescriptor.java

/*
 * Copyright 2009-2012 by The Regents of the University of California
 * 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 from
 * 
 *     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 edu.uci.ics.asterix.external.data.operator;

import java.util.Map;

import edu.uci.ics.asterix.external.adapter.factory.IAdapterFactory;
import edu.uci.ics.asterix.external.adapter.factory.IGenericDatasetAdapterFactory;
import edu.uci.ics.asterix.external.adapter.factory.ITypedDatasetAdapterFactory;
import edu.uci.ics.asterix.external.dataset.adapter.ITypedDatasourceAdapter;
import edu.uci.ics.asterix.external.feed.lifecycle.FeedId;
import edu.uci.ics.asterix.om.types.ARecordType;
import edu.uci.ics.asterix.om.types.IAType;
import edu.uci.ics.hyracks.api.context.IHyracksTaskContext;
import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
import edu.uci.ics.hyracks.api.job.JobSpecification;
import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;

/**
 * Operator responsible for ingesting data from an external source. This
 * operator uses a (configurable) adapter associated with the feed dataset.
 */
public class FeedIntakeOperatorDescriptor extends
		AbstractSingleActivityOperatorDescriptor {

	private static final long serialVersionUID = 1L;

	private final String adapterFactoryClassName;
	private final Map<String, String> adapterConfiguration;
	private final IAType atype;
	private final FeedId feedId;

	private transient IAdapterFactory datasourceAdapterFactory;

	public FeedIntakeOperatorDescriptor(JobSpecification spec, FeedId feedId,
			String adapter, Map<String, String> arguments, ARecordType atype,
			RecordDescriptor rDesc) {
		super(spec, 1, 1);
		recordDescriptors[0] = rDesc;
		this.adapterFactoryClassName = adapter;
		this.adapterConfiguration = arguments;
		this.atype = atype;
		this.feedId = feedId;
	}

	public IOperatorNodePushable createPushRuntime(IHyracksTaskContext ctx,
			IRecordDescriptorProvider recordDescProvider, final int partition,
			int nPartitions) throws HyracksDataException {
		ITypedDatasourceAdapter adapter;
		try {
			datasourceAdapterFactory = (IAdapterFactory) Class.forName(
					adapterFactoryClassName).newInstance();
			if (datasourceAdapterFactory instanceof IGenericDatasetAdapterFactory) {
				adapter = (ITypedDatasourceAdapter) ((IGenericDatasetAdapterFactory) datasourceAdapterFactory)
						.createAdapter(adapterConfiguration, atype);
			} else if (datasourceAdapterFactory instanceof ITypedDatasetAdapterFactory) {
				adapter = (ITypedDatasourceAdapter) ((ITypedDatasetAdapterFactory) datasourceAdapterFactory)
						.createAdapter(adapterConfiguration);
			} else {
				throw new IllegalStateException(
						" Unknown adapter factory type for "
								+ adapterFactoryClassName);
			}
			adapter.initialize(ctx);
		} catch (Exception e) {
			throw new HyracksDataException("initialization of adapter failed",
					e);
		}
		return new FeedIntakeOperatorNodePushable(feedId, adapter, partition);
	}
}