io.cdap.cdap.metadata.DefaultMetadataReader Maven / Gradle / Ivy
/*
* Copyright © 2018-2019 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 io.cdap.cdap.metadata;
import com.google.inject.Inject;
import io.cdap.cdap.api.metadata.Metadata;
import io.cdap.cdap.api.metadata.MetadataEntity;
import io.cdap.cdap.api.metadata.MetadataException;
import io.cdap.cdap.api.metadata.MetadataReader;
import io.cdap.cdap.api.metadata.MetadataScope;
import io.cdap.cdap.data2.metadata.MetadataCompatibility;
import io.cdap.cdap.spi.metadata.MetadataStorage;
import java.io.IOException;
import java.util.Map;
/**
* {@link MetadataReader} which should be used in local/in-memory mode where {@link MetadataAdmin} can be accessed
* directly i.e. the process is running as cdap system user and it can access the {@link MetadataStorage} which belongs
* to cdap user.
*
* This implementation should not be used in distributed program container or any process which is not running as
* cdap system user because the dataset operation will fail due to lack of privileges.
*/
public class DefaultMetadataReader implements MetadataReader {
private final MetadataAdmin metadataAdmin;
@Inject
public DefaultMetadataReader(MetadataAdmin metadataAdmin) {
this.metadataAdmin = metadataAdmin;
}
@Override
public Map getMetadata(MetadataEntity metadataEntity) throws MetadataException {
try {
return MetadataCompatibility.toV5Metadata(metadataAdmin.getMetadata(metadataEntity));
} catch (IOException e) {
throw new MetadataException(e);
}
}
@Override
public Metadata getMetadata(MetadataScope scope, MetadataEntity metadataEntity) throws MetadataException {
try {
return MetadataCompatibility.toV5Metadata(metadataAdmin.getMetadata(metadataEntity, scope), scope);
} catch (IOException e) {
throw new MetadataException(e);
}
}
}