rdblue commented on a change in pull request #1612: URL: https://github.com/apache/iceberg/pull/1612#discussion_r511143329
########## File path: mr/src/main/java/org/apache/iceberg/mr/hive/HiveSchemaUtil.java ########## @@ -0,0 +1,171 @@ +/* + * 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.iceberg.mr.hive; + +import java.util.ArrayList; +import java.util.Collections; +import java.util.List; +import org.apache.hadoop.hive.metastore.api.FieldSchema; +import org.apache.hadoop.hive.serde2.typeinfo.CharTypeInfo; +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.apache.iceberg.PartitionSpec; +import org.apache.iceberg.Schema; +import org.apache.iceberg.types.Types; + +public class HiveSchemaUtil { + private HiveSchemaUtil() { + } + + /** + * Converts the list of Hive FieldSchemas to an Iceberg schema. + * <p> + * The list should contain the columns and the partition columns as well. + * @param fieldSchemas The list of the columns + * @return An equivalent Iceberg Schema + */ + public static Schema schema(List<FieldSchema> fieldSchemas) { + List<String> names = new ArrayList<>(fieldSchemas.size()); + List<TypeInfo> typeInfos = new ArrayList<>(fieldSchemas.size()); + + for (FieldSchema col : fieldSchemas) { + names.add(col.getName()); + typeInfos.add(TypeInfoUtils.getTypeInfoFromTypeString(col.getType())); + } + + return convert(names, typeInfos); + } + + /** + * Converts the Hive properties defining the columns to an Iceberg schema. + * @param columnNames The property containing the column names + * @param columnTypes The property containing the column types + * @param columnNameDelimiter The name delimiter + * @return The Iceberg schema + */ + public static Schema schema(String columnNames, String columnTypes, String columnNameDelimiter) { + // Parse the configuration parameters + List<String> names = new ArrayList<>(); + Collections.addAll(names, columnNames.split(columnNameDelimiter)); + + return HiveSchemaUtil.convert(names, TypeInfoUtils.getTypeInfosFromTypeString(columnTypes)); + } + + /** + * Converts the Hive partition columns to Iceberg identity partition specification. + * @param schema The Iceberg schema + * @param fieldSchemas The partition column specification + * @return The Iceberg partition specification + */ + public static PartitionSpec spec(Schema schema, List<FieldSchema> fieldSchemas) { + PartitionSpec.Builder builder = PartitionSpec.builderFor(schema); + fieldSchemas.forEach(fieldSchema -> builder.identity(fieldSchema.getName())); + return builder.build(); + } + + private static Schema convert(List<String> names, List<TypeInfo> typeInfos) { + HiveSchemaVisitor visitor = new HiveSchemaVisitor(); + return new Schema(visitor.visit(names, typeInfos)); + } + + private static class HiveSchemaVisitor { + private int id; + + private HiveSchemaVisitor() { + id = 0; + } + + private List<Types.NestedField> visit(List<String> names, List<TypeInfo> typeInfos) { + List<Types.NestedField> result = new ArrayList<>(names.size()); + for (int i = 0; i < names.size(); ++i) { + result.add(visit(names.get(i), typeInfos.get(i))); + } + + return result; + } + + private Types.NestedField visit(String name, TypeInfo typeInfo) { + switch (typeInfo.getCategory()) { + case PRIMITIVE: + switch (((PrimitiveTypeInfo) typeInfo).getPrimitiveCategory()) { + case FLOAT: + return Types.NestedField.optional(id++, name, Types.FloatType.get()); + case DOUBLE: + return Types.NestedField.optional(id++, name, Types.DoubleType.get()); + case BOOLEAN: + return Types.NestedField.optional(id++, name, Types.BooleanType.get()); + case BYTE: + case SHORT: + case INT: + return Types.NestedField.optional(id++, name, Types.IntegerType.get()); + case LONG: + return Types.NestedField.optional(id++, name, Types.LongType.get()); + case BINARY: + return Types.NestedField.optional(id++, name, Types.BinaryType.get()); + case STRING: + case VARCHAR: + return Types.NestedField.optional(id++, name, Types.StringType.get()); + case CHAR: + Types.FixedType fixedType = Types.FixedType.ofLength(((CharTypeInfo) typeInfo).getLength()); + return Types.NestedField.optional(id++, name, fixedType); + case TIMESTAMP: + return Types.NestedField.optional(id++, name, Types.TimestampType.withZone()); Review comment: Does Hive support both TIMESTAMP WITH ZONE and WITHOUT ZONE? I thought that the default was WITHOUT ZONE, so I'm surprised to see the default here to with zone. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
