JingsongLi commented on a change in pull request #12010: URL: https://github.com/apache/flink/pull/12010#discussion_r422490558
########## File path: flink-formats/flink-json/src/main/java/org/apache/flink/formats/json/JsonFileSystemFormatFactory.java ########## @@ -0,0 +1,242 @@ +/* + * 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.flink.formats.json; + +import org.apache.flink.api.common.io.DelimitedInputFormat; +import org.apache.flink.api.common.io.InputFormat; +import org.apache.flink.api.common.serialization.BulkWriter; +import org.apache.flink.api.common.serialization.Encoder; +import org.apache.flink.api.java.typeutils.GenericTypeInfo; +import org.apache.flink.core.fs.FileInputSplit; +import org.apache.flink.core.fs.Path; +import org.apache.flink.table.data.GenericRowData; +import org.apache.flink.table.data.RowData; +import org.apache.flink.table.descriptors.DescriptorProperties; +import org.apache.flink.table.factories.FileSystemFormatFactory; +import org.apache.flink.table.types.DataType; +import org.apache.flink.table.types.logical.RowType; +import org.apache.flink.table.utils.PartitionPathUtils; + +import java.io.IOException; +import java.io.OutputStream; +import java.nio.charset.StandardCharsets; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.HashMap; +import java.util.List; +import java.util.Map; +import java.util.Optional; + +import static org.apache.flink.table.descriptors.FormatDescriptorValidator.FORMAT; +import static org.apache.flink.table.descriptors.JsonValidator.FORMAT_FAIL_ON_MISSING_FIELD; +import static org.apache.flink.table.descriptors.JsonValidator.FORMAT_IGNORE_PARSE_ERRORS; + +/** + * Factory to build reader/writer to read/write json format file. + */ +public class JsonFileSystemFormatFactory implements FileSystemFormatFactory { + + @Override + public Map<String, String> requiredContext() { + Map<String, String> context = new HashMap<>(); + context.put(FORMAT, "json"); + return context; + } + + @Override + public List<String> supportedProperties() { + ArrayList<String> properties = new ArrayList<>(); + properties.add(FORMAT_FAIL_ON_MISSING_FIELD); + properties.add(FORMAT_IGNORE_PARSE_ERRORS); + return properties; + } + + @Override + public InputFormat<RowData, ?> createReader(ReaderContext context) { + DescriptorProperties properties = getValidatedProperties(context.getFormatProperties()); + boolean failOnMissingField = properties.getOptionalBoolean(FORMAT_FAIL_ON_MISSING_FIELD).orElse(false); + boolean ignoreParseErrors = properties.getOptionalBoolean(FORMAT_IGNORE_PARSE_ERRORS).orElse(false); + + RowType nonPartRowType = context.getNonPartRowType(); + JsonRowDataDeserializationSchema deserializationSchema = new JsonRowDataDeserializationSchema( + nonPartRowType, + new GenericTypeInfo(GenericRowData.class), + failOnMissingField, + ignoreParseErrors); + + int[] jsonSelectFieldToProjectFieldMapping = context.getNonPartFieldProjectMapping(); + int[] jsonSelectFieldToJsonFieldMapping = context.getSelectFieldToNonPartFieldMapping(); + + return new JsonInputFormat( + context.getPaths(), + context.getSchema().getFieldDataTypes(), + context.getSchema().getFieldNames(), + context.getProjectFields(), + context.getPartitionKeys(), + context.getDefaultPartName(), + context.getPushedDownLimit(), + jsonSelectFieldToProjectFieldMapping, + jsonSelectFieldToJsonFieldMapping, + deserializationSchema); + } + + @Override + public Optional<Encoder<RowData>> createEncoder(WriterContext context) { + return Optional.of(new JsonRowDataEncoder(new JsonRowDataSerializationSchema(context.getNonPartRowType()))); + } + + @Override + public Optional<BulkWriter.Factory<RowData>> createBulkWriterFactory(WriterContext context) { + return Optional.empty(); + } + + @Override + public boolean supportsSchemaDerivation() { + return true; + } + + private static DescriptorProperties getValidatedProperties(Map<String, String> propertiesMap) { + final DescriptorProperties properties = new DescriptorProperties(true); + properties.putProperties(propertiesMap); + properties.validateBoolean(FORMAT_FAIL_ON_MISSING_FIELD, true); + properties.validateBoolean(FORMAT_IGNORE_PARSE_ERRORS, true); + return properties; + } + + /** + * A {@link JsonInputFormat} is responsible to read {@link RowData} records + * from json format files. + */ + public static class JsonInputFormat extends DelimitedInputFormat<RowData> { + /** + * Code of \r, used to remove \r from a line when the line ends with \r\n. + */ + private static final byte CARRIAGE_RETURN = (byte) '\r'; + + /** + * Code of \n, used to identify if \n is used as delimiter. + */ + private static final byte NEW_LINE = (byte) '\n'; + + private final DataType[] fieldTypes; + private final String[] fieldNames; + private final int[] selectFields; + private final List<String> partitionKeys; + private final String defaultPartValue; + private final long limit; + private final int[] jsonSelectFieldToProjectFieldMapping; + private final int[] jsonSelectFieldToJsonFieldMapping; + private final JsonRowDataDeserializationSchema deserializationSchema; + + private transient boolean end; + private transient long emitted; + // reuse object for per record + private transient GenericRowData rowData; + + public JsonInputFormat( + Path[] filePaths, + DataType[] fieldTypes, + String[] fieldNames, + int[] selectFields, + List<String> partitionKeys, + String defaultPartValue, + long limit, + int[] jsonSelectFieldToProjectFieldMapping, + int[] jsonSelectFieldToJsonFieldMapping, + JsonRowDataDeserializationSchema deserializationSchema) { + super.setFilePaths(filePaths); + this.fieldTypes = fieldTypes; + this.fieldNames = fieldNames; + this.selectFields = selectFields; + this.partitionKeys = partitionKeys; + this.defaultPartValue = defaultPartValue; + this.limit = limit; + this.jsonSelectFieldToProjectFieldMapping = jsonSelectFieldToProjectFieldMapping; + this.jsonSelectFieldToJsonFieldMapping = jsonSelectFieldToJsonFieldMapping; + this.deserializationSchema = deserializationSchema; + } + + @Override + public boolean supportsMultiPaths() { + return true; + } + + @Override + public void open(FileInputSplit split) throws IOException { + super.open(split); + this.end = false; + this.emitted = 0L; + this.rowData = PartitionPathUtils.fillPartitionValueForRecord(fieldNames, fieldTypes, selectFields, + partitionKeys, currentSplit.getPath(), defaultPartValue); + } + + @Override + public boolean reachedEnd() { + return emitted >= limit || end; + } + + @Override + public RowData readRecord(RowData reuse, byte[] bytes, int offset, int numBytes) throws IOException { + GenericRowData returnRecord = null; + do { + // remove \r from a line when the line ends with \r\n + if (this.getDelimiter() != null && this.getDelimiter().length == 1 + && this.getDelimiter()[0] == NEW_LINE && offset + numBytes >= 1 + && bytes[offset + numBytes - 1] == CARRIAGE_RETURN){ + numBytes -= 1; + } + byte[] trimBytes = Arrays.copyOfRange(bytes, offset, offset + numBytes); + GenericRowData jsonRow = (GenericRowData) deserializationSchema.deserialize(trimBytes); + + if (jsonRow != null) { + // if the record is null, simply just skip + returnRecord = rowData; + for (int i = 0; i < jsonSelectFieldToJsonFieldMapping.length; i++) { + returnRecord.setField(jsonSelectFieldToProjectFieldMapping[i], + jsonRow.getField(jsonSelectFieldToJsonFieldMapping[i])); + } + } + } while (returnRecord == null && !reachedEnd()); Review comment: ``` RowData readRecord() { ... if (jsonRow != null) { return null; } ... } RowData nextRecord() { while (true) { if (readLine()) { RowData row = readRecord(record, this.currBuffer, this.currOffset, this.currLen); if (row == null) { continue; } else { return row; } } else { this.end = true; return null; } } } ``` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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