/*
* Copyright © 2014 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.gateway.handlers;
import co.cask.cdap.api.common.Bytes;
import co.cask.cdap.api.dataset.DatasetProperties;
import co.cask.cdap.api.dataset.module.DatasetModule;
import co.cask.cdap.app.store.ServiceStore;
import co.cask.cdap.common.conf.CConfiguration;
import co.cask.cdap.common.conf.Constants;
import co.cask.cdap.data.Namespace;
import co.cask.cdap.data2.datafabric.DefaultDatasetNamespace;
import co.cask.cdap.data2.datafabric.dataset.DatasetsUtil;
import co.cask.cdap.data2.dataset2.DatasetDefinitionRegistryFactory;
import co.cask.cdap.data2.dataset2.DatasetFramework;
import co.cask.cdap.data2.dataset2.InMemoryDatasetFramework;
import co.cask.cdap.data2.dataset2.NamespacedDatasetFramework;
import co.cask.cdap.data2.dataset2.lib.kv.NoTxKeyValueTable;
import co.cask.tephra.TransactionFailureException;
import com.google.inject.Inject;
import com.google.inject.name.Named;
/**
* DataSetService Store implements ServiceStore using DataSets without Transaction.
*/
public final class DatasetServiceStore implements ServiceStore {
private final NoTxKeyValueTable table;
@Inject
public DatasetServiceStore(CConfiguration cConf, DatasetDefinitionRegistryFactory dsRegistryFactory,
@Named("serviceModule") DatasetModule datasetModule) throws Exception {
DatasetFramework dsFramework =
new NamespacedDatasetFramework(new InMemoryDatasetFramework(dsRegistryFactory),
new DefaultDatasetNamespace(cConf, Namespace.SYSTEM));
dsFramework.addModule("basicKVTable", datasetModule);
table = DatasetsUtil.getOrCreateDataset(dsFramework, Constants.Service.SERVICE_INSTANCE_TABLE_NAME,
NoTxKeyValueTable.class.getName(),
DatasetProperties.EMPTY, null, null);
}
@Override
public synchronized Integer getServiceInstance(final String serviceName) throws TransactionFailureException {
String count = Bytes.toString(table.get(Bytes.toBytes(serviceName)));
return (count != null) ? Integer.valueOf(count) : null;
}
@Override
public synchronized void setServiceInstance(final String serviceName, final int instances) {
table.put(Bytes.toBytes(serviceName), Bytes.toBytes(String.valueOf(instances)));
}
}