| # 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. | |
| from typing import Optional | |
| def truncate_upper_bound_text_string(value: str, trunc_length: Optional[int]) -> Optional[str]: | |
| result = value[:trunc_length] | |
| if result != value: | |
| chars = [*result] | |
| for i in range(-1, -len(result) - 1, -1): | |
| try: | |
| to_inc = ord(chars[i]) | |
| # will raise exception if the highest unicode code is reached | |
| _next = chr(to_inc + 1) | |
| chars[i] = _next | |
| return "".join(chars) | |
| except ValueError: | |
| pass | |
| return None # didn't find a valid upper bound | |
| return result | |
| def truncate_upper_bound_binary_string(value: bytes, trunc_length: Optional[int]) -> Optional[bytes]: | |
| result = value[:trunc_length] | |
| if result != value: | |
| _bytes = [*result] | |
| for i in range(-1, -len(result) - 1, -1): | |
| if _bytes[i] < 255: | |
| _bytes[i] += 1 | |
| return b"".join([i.to_bytes(1, byteorder="little") for i in _bytes]) | |
| return None | |
| return result | |