| /* |
| * 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.druid.sql.calcite.external; |
| |
| import com.fasterxml.jackson.core.JsonProcessingException; |
| import com.fasterxml.jackson.databind.ObjectMapper; |
| import org.apache.calcite.plan.Convention; |
| import org.apache.calcite.plan.RelOptCluster; |
| import org.apache.calcite.rel.AbstractRelNode; |
| import org.apache.calcite.rel.RelWriter; |
| import org.apache.calcite.rel.type.RelDataType; |
| import org.apache.druid.sql.calcite.table.DruidTable; |
| import org.apache.druid.sql.calcite.table.ExternalTable; |
| |
| /** |
| * Represents a scan of an external table. Generated by {@link ExternalTable}, |
| * which represents an {@link ExternalDataSource}. |
| * |
| * This class is exercised in CalciteInsertDmlTest but is not currently |
| * exposed to end users. |
| */ |
| public class ExternalTableScan extends AbstractRelNode |
| { |
| private final ObjectMapper jsonMapper; |
| private final ExternalTable druidTable; |
| |
| public ExternalTableScan( |
| final RelOptCluster cluster, |
| final ObjectMapper jsonMapper, |
| final ExternalTable druidTable |
| ) |
| { |
| super(cluster, cluster.traitSetOf(Convention.NONE)); |
| this.jsonMapper = jsonMapper; |
| this.druidTable = druidTable; |
| } |
| |
| public DruidTable getDruidTable() |
| { |
| return druidTable; |
| } |
| |
| @Override |
| protected RelDataType deriveRowType() |
| { |
| return druidTable.getRowType(getCluster().getTypeFactory()); |
| } |
| |
| @Override |
| public RelWriter explainTerms(RelWriter pw) |
| { |
| final String dataSourceString; |
| |
| try { |
| dataSourceString = jsonMapper.writeValueAsString(druidTable.getDataSource()); |
| } |
| catch (JsonProcessingException e) { |
| throw new RuntimeException(e); |
| } |
| |
| return pw.item("dataSource", dataSourceString); |
| } |
| } |