/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.drill.exec.store.sys;
import java.io.IOException;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import com.google.common.collect.ImmutableList;
import net.hydromatic.optiq.SchemaPlus;
import org.apache.drill.common.JSONOptions;
import org.apache.drill.common.expression.SchemaPath;
import org.apache.drill.common.logical.StoragePluginConfig;
import org.apache.drill.exec.ops.FragmentContext;
import org.apache.drill.exec.physical.base.AbstractGroupScan;
import org.apache.drill.exec.planner.logical.DrillTable;
import org.apache.drill.exec.rpc.user.UserSession;
import org.apache.drill.exec.server.DrillbitContext;
import org.apache.drill.exec.server.options.DrillConfigIterator;
import org.apache.drill.exec.server.options.OptionValue;
import org.apache.drill.exec.store.AbstractSchema;
import org.apache.drill.exec.store.AbstractStoragePlugin;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import com.google.common.collect.Iterables;
public class SystemTablePlugin extends AbstractStoragePlugin{
static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(SystemTablePlugin.class);
private final DrillbitContext context;
private final String name;
public SystemTablePlugin(SystemTablePluginConfig configuration, DrillbitContext context, String name){
this.context = context;
this.name = name;
}
private SystemSchema schema = new SystemSchema();
@Override
public StoragePluginConfig getConfig() {
return SystemTablePluginConfig.INSTANCE;
}
@Override
public void registerSchemas(UserSession session, SchemaPlus parent) {
parent.add(schema.getName(), schema);
}
public Iterator<Object> getRecordIterator(FragmentContext context, SystemTable table){
switch(table){
case DRILLBITS:
return new DrillbitIterator(context);
case OPTION:
return Iterables.concat((Iterable<Object>)(Object) new DrillConfigIterator(context.getConfig()), //
context.getOptions()).iterator();
default:
throw new UnsupportedOperationException("Unable to create record iterator for table: " + table.getTableName());
}
}
@Override
public AbstractGroupScan getPhysicalScan(JSONOptions selection, List<SchemaPath> columns) throws IOException {
SystemTable table = selection.getWith(context.getConfig(), SystemTable.class);
return new SystemTableScan(table, this);
}
private class SystemSchema extends AbstractSchema{
private Set<String> tableNames;
public SystemSchema() {
super(ImmutableList.<String>of(), "sys");
Set<String> names = Sets.newHashSet();
for(SystemTable t : SystemTable.values()){
names.add(t.getTableName());
}
this.tableNames = ImmutableSet.copyOf(names);
}
@Override
public Set<String> getTableNames() {
return tableNames;
}
@Override
public DrillTable getTable(String name) {
for(SystemTable table : SystemTable.values()){
if(table.getTableName().equalsIgnoreCase(name)){
return new StaticDrillTable(table.getType(), SystemTablePlugin.this.name, SystemTablePlugin.this, table);
}
}
return null;
}
@Override
public String getTypeName() {
return SystemTablePluginConfig.NAME;
}
}
}