asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/entities/ExternalDatasetDetails.java

/*
 * Copyright 2009-2011 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.metadata.entities;

import java.io.DataOutput;
import java.io.IOException;
import java.util.Map;

import edu.uci.ics.asterix.builders.IARecordBuilder;
import edu.uci.ics.asterix.builders.OrderedListBuilder;
import edu.uci.ics.asterix.builders.RecordBuilder;
import edu.uci.ics.asterix.common.config.DatasetConfig.DatasetType;
import edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider;
import edu.uci.ics.asterix.metadata.IDatasetDetails;
import edu.uci.ics.asterix.metadata.bootstrap.MetadataRecordTypes;
import edu.uci.ics.asterix.om.base.AMutableString;
import edu.uci.ics.asterix.om.base.AString;
import edu.uci.ics.asterix.om.types.AOrderedListType;
import edu.uci.ics.asterix.om.types.ARecordType;
import edu.uci.ics.asterix.om.types.BuiltinType;
import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
import edu.uci.ics.hyracks.data.std.util.ArrayBackedValueStorage;

public class ExternalDatasetDetails implements IDatasetDetails {

    private static final long serialVersionUID = 1L;
    private final String adapter;
    private final Map<String, String> properties;

    private final static ARecordType externalRecordType = MetadataRecordTypes.EXTERNAL_DETAILS_RECORDTYPE;
    private final static ARecordType propertyRecordType = MetadataRecordTypes.DATASOURCE_ADAPTER_PROPERTIES_RECORDTYPE;

    public ExternalDatasetDetails(String adapter, Map<String, String> properties) {
        this.properties = properties;
        this.adapter = adapter;
    }

    public String getAdapter() {
        return adapter;
    }

    public Map<String, String> getProperties() {
        return properties;
    }

    @Override
    public DatasetType getDatasetType() {
        return DatasetType.EXTERNAL;
    }

    @Override
    public void writeDatasetDetailsRecordType(DataOutput out) throws HyracksDataException {
        IARecordBuilder externalRecordBuilder = new RecordBuilder();
        OrderedListBuilder listBuilder = new OrderedListBuilder();
        ArrayBackedValueStorage fieldValue = new ArrayBackedValueStorage();
        ArrayBackedValueStorage itemValue = new ArrayBackedValueStorage();
        externalRecordBuilder.reset(externalRecordType);
        AMutableString aString = new AMutableString("");
        ISerializerDeserializer<AString> stringSerde = AqlSerializerDeserializerProvider.INSTANCE
                .getSerializerDeserializer(BuiltinType.ASTRING);

        // write field 0
        fieldValue.reset();
        aString.setValue(this.getAdapter());
        stringSerde.serialize(aString, fieldValue.getDataOutput());
        externalRecordBuilder.addField(MetadataRecordTypes.EXTERNAL_DETAILS_ARECORD_DATASOURCE_ADAPTER_FIELD_INDEX, fieldValue);

        // write field 1
        listBuilder.reset((AOrderedListType) externalRecordType.getFieldTypes()[1]);
        for (Map.Entry<String, String> property : this.properties.entrySet()) {
            String name = property.getKey();
            String value = property.getValue();
            itemValue.reset();
            writePropertyTypeRecord(name, value, itemValue.getDataOutput());
            listBuilder.addItem(itemValue);
        }
        fieldValue.reset();
        listBuilder.write(fieldValue.getDataOutput(), true);
        externalRecordBuilder.addField(MetadataRecordTypes.EXTERNAL_DETAILS_ARECORD_PROPERTIES_FIELD_INDEX, fieldValue);

        try {
            externalRecordBuilder.write(out, true);
        } catch (IOException ioe) {
            throw new HyracksDataException(ioe);
        }

    }

    public void writePropertyTypeRecord(String name, String value, DataOutput out) throws HyracksDataException {
        IARecordBuilder propertyRecordBuilder = new RecordBuilder();
        ArrayBackedValueStorage fieldValue = new ArrayBackedValueStorage();
        propertyRecordBuilder.reset(propertyRecordType);
        AMutableString aString = new AMutableString("");
        ISerializerDeserializer<AString> stringSerde = AqlSerializerDeserializerProvider.INSTANCE
                .getSerializerDeserializer(BuiltinType.ASTRING);

        // write field 0
        fieldValue.reset();
        aString.setValue(name);
        stringSerde.serialize(aString, fieldValue.getDataOutput());
        propertyRecordBuilder.addField(0, fieldValue);

        // write field 1
        fieldValue.reset();
        aString.setValue(value);
        stringSerde.serialize(aString, fieldValue.getDataOutput());
        propertyRecordBuilder.addField(1, fieldValue);

        try {
            propertyRecordBuilder.write(out, true);
        } catch (IOException ioe) {
            throw new HyracksDataException(ioe);
        }
    }
}