| """ |
| Script to automatically generate a JSON file containing time zone information. |
| |
| This is done to allow "pinning" a small subset of the tzdata in the tests, |
| since we are testing properties of a file that may be subject to change. For |
| example, the behavior in the far future of any given zone is likely to change, |
| but "does this give the right answer for this file in 2040" is still an |
| important property to test. |
| |
| This must be run from a computer with zoneinfo data installed. |
| """ |
| from __future__ import annotations |
| |
| import base64 |
| import functools |
| import json |
| import lzma |
| import pathlib |
| import textwrap |
| import typing |
| |
| import zoneinfo |
| |
| KEYS = [ |
| "Africa/Abidjan", |
| "Africa/Casablanca", |
| "America/Los_Angeles", |
| "America/Santiago", |
| "Asia/Tokyo", |
| "Australia/Sydney", |
| "Europe/Dublin", |
| "Europe/Lisbon", |
| "Europe/London", |
| "Pacific/Kiritimati", |
| "UTC", |
| ] |
| |
| TEST_DATA_LOC = pathlib.Path(__file__).parent |
| |
| |
| @functools.lru_cache(maxsize=None) |
| def get_zoneinfo_path() -> pathlib.Path: |
| """Get the first zoneinfo directory on TZPATH containing the "UTC" zone.""" |
| key = "UTC" |
| for path in map(pathlib.Path, zoneinfo.TZPATH): |
| if (path / key).exists(): |
| return path |
| else: |
| raise OSError("Cannot find time zone data.") |
| |
| |
| def get_zoneinfo_metadata() -> typing.Dict[str, str]: |
| path = get_zoneinfo_path() |
| |
| tzdata_zi = path / "tzdata.zi" |
| if not tzdata_zi.exists(): |
| # tzdata.zi is necessary to get the version information |
| raise OSError("Time zone data does not include tzdata.zi.") |
| |
| with open(tzdata_zi, "r") as f: |
| version_line = next(f) |
| |
| _, version = version_line.strip().rsplit(" ", 1) |
| |
| if ( |
| not version[0:4].isdigit() |
| or len(version) < 5 |
| or not version[4:].isalpha() |
| ): |
| raise ValueError( |
| "Version string should be YYYYx, " |
| + "where YYYY is the year and x is a letter; " |
| + f"found: {version}" |
| ) |
| |
| return {"version": version} |
| |
| |
| def get_zoneinfo(key: str) -> bytes: |
| path = get_zoneinfo_path() |
| |
| with open(path / key, "rb") as f: |
| return f.read() |
| |
| |
| def encode_compressed(data: bytes) -> typing.List[str]: |
| compressed_zone = lzma.compress(data) |
| raw = base64.b85encode(compressed_zone) |
| |
| raw_data_str = raw.decode("utf-8") |
| |
| data_str = textwrap.wrap(raw_data_str, width=70) |
| return data_str |
| |
| |
| def load_compressed_keys() -> typing.Dict[str, typing.List[str]]: |
| output = {key: encode_compressed(get_zoneinfo(key)) for key in KEYS} |
| |
| return output |
| |
| |
| def update_test_data(fname: str = "zoneinfo_data.json") -> None: |
| TEST_DATA_LOC.mkdir(exist_ok=True, parents=True) |
| |
| # Annotation required: https://github.com/python/mypy/issues/8772 |
| json_kwargs: typing.Dict[str, typing.Any] = dict( |
| indent=2, sort_keys=True, |
| ) |
| |
| compressed_keys = load_compressed_keys() |
| metadata = get_zoneinfo_metadata() |
| output = { |
| "metadata": metadata, |
| "data": compressed_keys, |
| } |
| |
| with open(TEST_DATA_LOC / fname, "w") as f: |
| json.dump(output, f, **json_kwargs) |
| |
| |
| if __name__ == "__main__": |
| update_test_data() |