snuyanzin commented on code in PR #24967: URL: https://github.com/apache/flink/pull/24967#discussion_r1673910427
########## flink-table/flink-table-runtime/src/main/java/org/apache/flink/table/runtime/functions/scalar/JsonUnquoteFunction.java: ########## @@ -0,0 +1,128 @@ +/* + * 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.table.runtime.functions.scalar; + +import org.apache.flink.annotation.Internal; +import org.apache.flink.table.data.binary.BinaryStringData; +import org.apache.flink.table.functions.BuiltInFunctionDefinitions; +import org.apache.flink.table.functions.SpecializedFunction.SpecializedContext; +import org.apache.flink.table.runtime.functions.SqlJsonUtils; + +import javax.annotation.Nullable; + +/** Implementation of {@link BuiltInFunctionDefinitions#JSON_UNQUOTE}. */ +@Internal +public class JsonUnquoteFunction extends BuiltInScalarFunction { + + public JsonUnquoteFunction(SpecializedContext context) { + super(BuiltInFunctionDefinitions.JSON_UNQUOTE, context); + } + + private static boolean isValidJsonVal(String jsonInString) { + // See also BuiltInMethods.scala, IS_JSON_VALUE + return SqlJsonUtils.isJsonValue(jsonInString); + } + + private String unescapeStr(String inputStr) { + StringBuilder result = new StringBuilder(); + int i = 0; + while (i < inputStr.length()) { + if (inputStr.charAt(i) == '\\' && i + 1 < inputStr.length()) { + i++; // move to the next char + char ch = inputStr.charAt(i++); + + switch (ch) { + case '"': + result.append(ch); + break; + case '\\': + result.append(ch); + break; + case '/': + result.append(ch); + break; + case 'b': + result.append('\b'); + break; + case 'f': + result.append('\f'); + break; + case 'n': + result.append('\n'); + break; + case 'r': + result.append('\r'); + break; + case 't': + result.append('\t'); + break; + case 'u': + result.append(fromUnicodeLiteral(inputStr, i)); + i = i + 4; + break; + default: + throw new RuntimeException("Illegal escape sequence: \\" + ch); + } + } else { + result.append(inputStr.charAt(i)); + i++; + } + } + return result.toString(); + } + + private String unescapeValidJson(String inputStr) { + // check for a quoted json string val and unescape + if (inputStr.charAt(0) == '"' && inputStr.charAt(inputStr.length() - 1) == '"') { + // remove quotes, string len is atleast 2 here + return unescapeStr(inputStr.substring(1, inputStr.length() - 1)); + } else { + // string representing Json - array, object or unquoted scalar val, return as-is + return inputStr; + } + } + + private static String fromUnicodeLiteral(String input, int curPos) { + + StringBuilder number = new StringBuilder(); + // isValidJsonVal will already check for unicode literal validity + for (char ch : input.substring(curPos, curPos + 4).toCharArray()) { + number.append(Character.toLowerCase(ch)); + } + int code = Integer.parseInt(number.toString(), 16); + return String.valueOf((char) code); + } + + public @Nullable Object eval(Object input) { Review Comment: nit: usually we put public methods above and utility private methods below e.g. https://github.com/apache/flink/blob/master/flink-table/flink-sql-parser/src/main/java/org/apache/calcite/sql/fun/SqlJsonQueryFunction.java -- 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. To unsubscribe, e-mail: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
