ihuzenko commented on a change in pull request #1559: DRILL-540: Allow querying hive views in Drill URL: https://github.com/apache/drill/pull/1559#discussion_r242920560
########## File path: contrib/storage-hive/core/src/main/java/org/apache/drill/exec/planner/types/HiveToRelDataTypeConverter.java ########## @@ -0,0 +1,158 @@ +/* + * 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.planner.types; + +import java.util.List; +import java.util.stream.Collectors; + +import org.apache.calcite.rel.type.RelDataType; +import org.apache.calcite.rel.type.RelDataTypeFactory; +import org.apache.calcite.sql.SqlCollation; +import org.apache.calcite.sql.type.SqlTypeName; +import org.apache.calcite.util.Util; +import org.apache.hadoop.hive.metastore.api.FieldSchema; +import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector.Category; +import org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector; +import org.apache.hadoop.hive.serde2.typeinfo.DecimalTypeInfo; +import org.apache.hadoop.hive.serde2.typeinfo.ListTypeInfo; +import org.apache.hadoop.hive.serde2.typeinfo.MapTypeInfo; +import org.apache.hadoop.hive.serde2.typeinfo.PrimitiveTypeInfo; +import org.apache.hadoop.hive.serde2.typeinfo.StructTypeInfo; +import org.apache.hadoop.hive.serde2.typeinfo.TypeInfo; +import org.apache.hadoop.hive.serde2.typeinfo.TypeInfoUtils; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * This class is responsible for data type conversions + * from {@link org.apache.hadoop.hive.metastore.api.FieldSchema} instances + * to {@link org.apache.calcite.rel.type.RelDataType} instances + */ +public class HiveToRelDataTypeConverter { + + private static final Logger logger = LoggerFactory.getLogger(HiveToRelDataTypeConverter.class); + + private static final String UNSUPPORTED_HIVE_DATA_TYPE_ERROR_MSG = "Unsupported Hive data type %s. %n" + + "Following Hive data types are supported in Drill INFORMATION_SCHEMA: " + + "BOOLEAN, BYTE, SHORT, INT, LONG, FLOAT, DOUBLE, DATE, TIMESTAMP, BINARY, DECIMAL, STRING, " + + "VARCHAR, CHAR, LIST, MAP, STRUCT and UNION"; + + + private final RelDataTypeFactory typeFactory; + + public HiveToRelDataTypeConverter(RelDataTypeFactory typeFactory) { + this.typeFactory = typeFactory; + } + + /** + * Performs conversion from Hive field to nullable RelDataType + * + * @param field - representation of data type in Hive Metastore + * @return appropriate nullable RelDataType for using with Calcite + * @throws RuntimeException for unsupported data types, check + * {@link HiveToRelDataTypeConverter#UNSUPPORTED_HIVE_DATA_TYPE_ERROR_MSG} + * for details about supported hive types + */ + public RelDataType convertToNullableRelDataType(FieldSchema field) { + TypeInfo fieldTypeInfo = TypeInfoUtils.getTypeInfoFromTypeString(field.getType()); + RelDataType relDataType = convertToRelDataType(fieldTypeInfo); + return typeFactory.createTypeWithNullability(relDataType, true); + } + + private RelDataType convertToRelDataType(TypeInfo typeInfo) { + final Category typeCategory = typeInfo.getCategory(); + switch (typeCategory) { + case PRIMITIVE: + return getRelDataType((PrimitiveTypeInfo) typeInfo); + case LIST: + return getRelDataType((ListTypeInfo) typeInfo); + case MAP: + return getRelDataType((MapTypeInfo) typeInfo); + case STRUCT: + return getRelDataType((StructTypeInfo) typeInfo); + case UNION: + logger.warn("There is no UNION data type in SQL. Converting it to Sql type OTHER to avoid " + + "breaking INFORMATION_SCHEMA queries"); + return typeFactory.createSqlType(SqlTypeName.OTHER); + } + throw new RuntimeException(String.format(UNSUPPORTED_HIVE_DATA_TYPE_ERROR_MSG, typeCategory)); + } + + private RelDataType getRelDataType(StructTypeInfo structTypeInfo) { + final List<String> fieldNames = structTypeInfo.getAllStructFieldNames(); + final List<RelDataType> relDataTypes = structTypeInfo.getAllStructFieldTypeInfos() + .stream() + .map(this::convertToRelDataType) + .collect(Collectors.toList()); + return typeFactory.createStructType(relDataTypes, fieldNames); + } + + private RelDataType getRelDataType(MapTypeInfo mapTypeInfo) { + RelDataType keyType = convertToRelDataType(mapTypeInfo.getMapKeyTypeInfo()); + RelDataType valueType = convertToRelDataType(mapTypeInfo.getMapValueTypeInfo()); + return typeFactory.createMapType(keyType, valueType); + } + + private RelDataType getRelDataType(ListTypeInfo listTypeInfo) { + RelDataType listElemTypeInfo = convertToRelDataType(listTypeInfo.getListElementTypeInfo()); + return typeFactory.createArrayType(listElemTypeInfo, -1); + } + + private RelDataType getRelDataType(PrimitiveTypeInfo primitiveTypeInfo) { + final PrimitiveObjectInspector.PrimitiveCategory primitiveCategory = primitiveTypeInfo.getPrimitiveCategory(); + switch (primitiveCategory) { + case STRING: + case VARCHAR: + return getRelDataType(primitiveTypeInfo, SqlTypeName.VARCHAR); + case CHAR: + return getRelDataType(primitiveTypeInfo, SqlTypeName.CHAR); + case BYTE: + case SHORT: + case INT: + return typeFactory.createSqlType(SqlTypeName.INTEGER); + case DECIMAL: + return getRelDataType((DecimalTypeInfo) primitiveTypeInfo); + case BOOLEAN: + return typeFactory.createSqlType(SqlTypeName.BOOLEAN); + case LONG: + return typeFactory.createSqlType(SqlTypeName.BIGINT); + case FLOAT: + return typeFactory.createSqlType(SqlTypeName.FLOAT); + case DOUBLE: + return typeFactory.createSqlType(SqlTypeName.DOUBLE); + case DATE: + return typeFactory.createSqlType(SqlTypeName.DATE); + case TIMESTAMP: + return typeFactory.createSqlType(SqlTypeName.TIMESTAMP); + case BINARY: + return typeFactory.createSqlType(SqlTypeName.VARBINARY); + } + throw new RuntimeException(String.format(UNSUPPORTED_HIVE_DATA_TYPE_ERROR_MSG, primitiveCategory)); + } + + private RelDataType getRelDataType(PrimitiveTypeInfo pTypeInfo, SqlTypeName typeName) { + int maxLen = TypeInfoUtils.getCharacterLengthForType(pTypeInfo); + RelDataType relDataType = typeFactory.createSqlType(typeName, maxLen); + return typeFactory.createTypeWithCharsetAndCollation(relDataType, Util.getDefaultCharset(), + SqlCollation.IMPLICIT); + } + + private RelDataType getRelDataType(DecimalTypeInfo decimalTypeInfo) { + return typeFactory.createSqlType(SqlTypeName.DECIMAL, decimalTypeInfo.precision(), decimalTypeInfo.scale()); + } +} Review comment: done ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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