wuchong commented on a change in pull request #11944: URL: https://github.com/apache/flink/pull/11944#discussion_r417375698
########## File path: flink-formats/flink-json/src/main/java/org/apache/flink/formats/json/JsonRowDataDeserializationSchema.java ########## @@ -0,0 +1,492 @@ +/* + * 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.annotation.Internal; +import org.apache.flink.api.common.serialization.DeserializationSchema; +import org.apache.flink.api.common.typeinfo.TypeInformation; +import org.apache.flink.table.data.DecimalData; +import org.apache.flink.table.data.GenericArrayData; +import org.apache.flink.table.data.GenericMapData; +import org.apache.flink.table.data.GenericRowData; +import org.apache.flink.table.data.RowData; +import org.apache.flink.table.data.StringData; +import org.apache.flink.table.data.TimestampData; +import org.apache.flink.table.types.logical.ArrayType; +import org.apache.flink.table.types.logical.DecimalType; +import org.apache.flink.table.types.logical.LogicalType; +import org.apache.flink.table.types.logical.LogicalTypeFamily; +import org.apache.flink.table.types.logical.MapType; +import org.apache.flink.table.types.logical.RowType; +import org.apache.flink.table.types.logical.utils.LogicalTypeChecks; +import org.apache.flink.table.types.logical.utils.LogicalTypeUtils; + +import org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.JsonNode; +import org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.ObjectMapper; +import org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ArrayNode; +import org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode; +import org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.TextNode; + +import java.io.IOException; +import java.io.Serializable; +import java.lang.reflect.Array; +import java.math.BigDecimal; +import java.time.LocalDate; +import java.time.LocalDateTime; +import java.time.LocalTime; +import java.time.ZoneOffset; +import java.time.temporal.TemporalAccessor; +import java.time.temporal.TemporalQueries; +import java.util.HashMap; +import java.util.Iterator; +import java.util.Map; + +import static java.lang.String.format; +import static java.time.format.DateTimeFormatter.ISO_LOCAL_DATE; +import static org.apache.flink.formats.json.TimeFormats.RFC3339_TIMESTAMP_FORMAT; +import static org.apache.flink.formats.json.TimeFormats.RFC3339_TIME_FORMAT; +import static org.apache.flink.util.Preconditions.checkNotNull; + +/** + * Deserialization schema from JSON to Flink Table/SQL internal data structure {@link RowData}. + * + * <p>Deserializes a <code>byte[]</code> message as a JSON object and reads + * the specified fields. + * + * <p>Failures during deserialization are forwarded as wrapped IOExceptions. + */ +@Internal +public class JsonRowDataDeserializationSchema implements DeserializationSchema<RowData> { + private static final long serialVersionUID = 8576854315236033439L; + + /** Flag indicating whether to fail if a field is missing. */ + private final boolean failOnMissingField; + + /** Flag indicating whether to ignore invalid fields/rows (default: throw an exception). */ + private final boolean ignoreParseErrors; + + /** TypeInformation of the produced {@link RowData}. **/ + private final TypeInformation<RowData> resultTypeInfo; + + /** + * Runtime converter that converts {@link JsonNode}s into + * objects of Flink SQL internal data structures. **/ + private final DeserializationRuntimeConverter runtimeConverter; + + /** Object mapper for parsing the JSON. */ + private final ObjectMapper objectMapper = new ObjectMapper(); + + /** + * Creates a builder for {@link JsonRowDataDeserializationSchema}. + */ + public static Builder builder() { + return new Builder(); + } + + private JsonRowDataDeserializationSchema( + RowType rowType, + TypeInformation<RowData> resultTypeInfo, + boolean failOnMissingField, + boolean ignoreParseErrors) { + if (ignoreParseErrors && failOnMissingField) { + throw new IllegalArgumentException( + "JSON format doesn't support failOnMissingField and ignoreParseErrors are both enabled."); + } + this.resultTypeInfo = checkNotNull(resultTypeInfo); + this.failOnMissingField = failOnMissingField; + this.ignoreParseErrors = ignoreParseErrors; + this.runtimeConverter = createRowConverter(checkNotNull(rowType)); + } + + @Override + public RowData deserialize(byte[] message) throws IOException { + try { + final JsonNode root = objectMapper.readTree(message); + return (RowData) runtimeConverter.convert(root); + } catch (Throwable t) { + if (ignoreParseErrors) { + return null; + } + throw new IOException(format("Failed to deserialize JSON '%s'.", new String(message)), t); + } + } + + @Override + public boolean isEndOfStream(RowData nextElement) { + return false; + } + + @Override + public TypeInformation<RowData> getProducedType() { + return resultTypeInfo; + } + + // ------------------------------------------------------------------------------------- + // Builder + // ------------------------------------------------------------------------------------- + + /** + * Builder for {@link JsonRowDataDeserializationSchema}. + */ + public static class Builder { Review comment: I think we will support more and more options for JSON in the future. A builder is more friendly to evolve without breaking constructors. But I'm also fine to remove builders because this is an `@Internal` class. ---------------------------------------------------------------- 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: us...@infra.apache.org
