/*
* 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.api.dataset.lib;
import co.cask.cdap.api.app.ApplicationConfigurer;
import co.cask.cdap.api.dataset.DatasetProperties;
import co.cask.cdap.internal.io.ReflectionSchemaGenerator;
import co.cask.cdap.internal.io.Schema;
import co.cask.cdap.internal.io.SchemaTypeAdapter;
import co.cask.cdap.internal.io.TypeRepresentation;
import co.cask.cdap.internal.io.UnsupportedTypeException;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import java.lang.reflect.Type;
/**
* Utility for describing {@link ObjectStore} and similar datasets within application configuration.
*/
public final class ObjectStores {
private static final Gson GSON = new GsonBuilder()
.registerTypeAdapter(Schema.class, new SchemaTypeAdapter())
.create();
private ObjectStores() {}
/**
* Adds {@link ObjectStore} dataset to be created at application deploy if not exists.
* @param configurer application configurer
* @param datasetName dataset name
* @param type type of objects to be stored in {@link ObjectStore}
* @param props any additional dataset properties
* @throws UnsupportedTypeException
*/
public static void createObjectStore(ApplicationConfigurer configurer,
String datasetName, Type type, DatasetProperties props)
throws UnsupportedTypeException {
configurer.createDataset(datasetName, ObjectStore.class, objectStoreProperties(type, props));
}
/**
* Same as {@link #createObjectStore(ApplicationConfigurer, String, Type, DatasetProperties)} but with empty
* properties.
*/
public static void createObjectStore(ApplicationConfigurer configurer, String datasetName, Type type)
throws UnsupportedTypeException {
createObjectStore(configurer, datasetName, type, DatasetProperties.EMPTY);
}
/**
* Adds {@link IndexedObjectStore} dataset to be created at application deploy if not exists.
* @param configurer application configurer
* @param datasetName dataset name
* @param type type of objects to be stored in {@link IndexedObjectStore}
* @param props any additional dataset properties
* @throws UnsupportedTypeException
*/
public static void createIndexedObjectStore(ApplicationConfigurer configurer,
String datasetName, Type type, DatasetProperties props)
throws UnsupportedTypeException {
configurer.createDataset(datasetName, IndexedObjectStore.class, objectStoreProperties(type, props));
}
/**
* Same as {@link #createIndexedObjectStore(ApplicationConfigurer, String, Type, DatasetProperties)} but with empty
* properties.
*/
public static void createIndexedObjectStore(ApplicationConfigurer configurer, String datasetName, Type type)
throws UnsupportedTypeException {
createIndexedObjectStore(configurer, datasetName, type, DatasetProperties.EMPTY);
}
/**
* Creates properties for {@link ObjectStore} dataset instance.
* @param type type of objects to be stored in dataset
* @return {@link DatasetProperties} for the dataset
* @throws UnsupportedTypeException
*/
public static DatasetProperties objectStoreProperties(Type type, DatasetProperties props)
throws UnsupportedTypeException {
Schema schema = new ReflectionSchemaGenerator().generate(type);
TypeRepresentation typeRep = new TypeRepresentation(type);
return DatasetProperties.builder()
.add("schema", GSON.toJson(schema))
.add("type", GSON.toJson(typeRep))
.addAll(props.getProperties())
.build();
}
}