/*
* Copyright © 2016 Cask Data, Inc.
*
* 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 co.cask.cdap.data2.metadata.system;
import co.cask.cdap.api.data.format.FormatSpecification;
import co.cask.cdap.api.data.format.RecordFormat;
import co.cask.cdap.api.data.schema.Schema;
import co.cask.cdap.api.data.schema.UnsupportedTypeException;
import co.cask.cdap.data2.metadata.store.MetadataStore;
import co.cask.cdap.format.RecordFormats;
import co.cask.cdap.proto.Id;
import co.cask.cdap.proto.ViewSpecification;
import com.google.common.collect.ImmutableMap;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Map;
import javax.annotation.Nullable;
/**
* A {@link AbstractSystemMetadataWriter} for an {@link Id.Stream.View view}.
*/
public class ViewSystemMetadataWriter extends AbstractSystemMetadataWriter {
private static final Logger LOG = LoggerFactory.getLogger(ViewSystemMetadataWriter.class);
private final Id.Stream.View viewId;
private final ViewSpecification viewSpec;
public ViewSystemMetadataWriter(MetadataStore metadataStore, Id.Stream.View viewId, ViewSpecification viewSpec) {
super(metadataStore, viewId);
this.viewId = viewId;
this.viewSpec = viewSpec;
}
@Override
protected Map<String, String> getSystemPropertiesToAdd() {
ImmutableMap.Builder<String, String> properties = ImmutableMap.builder();
return properties.build();
}
@Override
protected String[] getSystemTagsToAdd() {
return new String[] {
viewId.getId(),
viewId.getStreamId()
};
}
@Nullable
@Override
protected String getSchemaToAdd() {
Schema schema = viewSpec.getFormat().getSchema();
if (schema == null) {
FormatSpecification format = viewSpec.getFormat();
RecordFormat<Object, Object> initializedFormat = null;
try {
initializedFormat = RecordFormats.createInitializedFormat(format);
schema = initializedFormat.getSchema();
} catch (IllegalAccessException | InstantiationException | UnsupportedTypeException | ClassNotFoundException e) {
LOG.debug("Exception: ", e);
LOG.warn("Exception while determining schema for view {}. View {} will not contain schema as metadata.", viewId,
viewId);
}
}
return schema == null ? null : schema.toString();
}
}