| | import os |
| | import sysconfig |
| |
|
| |
|
| | def reset_tzpath(to=None): |
| | global TZPATH |
| |
|
| | tzpaths = to |
| | if tzpaths is not None: |
| | if isinstance(tzpaths, (str, bytes)): |
| | raise TypeError( |
| | f"tzpaths must be a list or tuple, " |
| | + f"not {type(tzpaths)}: {tzpaths!r}" |
| | ) |
| |
|
| | if not all(map(os.path.isabs, tzpaths)): |
| | raise ValueError(_get_invalid_paths_message(tzpaths)) |
| | base_tzpath = tzpaths |
| | else: |
| | env_var = os.environ.get("PYTHONTZPATH", None) |
| | if env_var is not None: |
| | base_tzpath = _parse_python_tzpath(env_var) |
| | else: |
| | base_tzpath = _parse_python_tzpath( |
| | sysconfig.get_config_var("TZPATH") |
| | ) |
| |
|
| | TZPATH = tuple(base_tzpath) |
| |
|
| |
|
| | def _parse_python_tzpath(env_var): |
| | if not env_var: |
| | return () |
| |
|
| | raw_tzpath = env_var.split(os.pathsep) |
| | new_tzpath = tuple(filter(os.path.isabs, raw_tzpath)) |
| |
|
| | |
| | if len(new_tzpath) != len(raw_tzpath): |
| | import warnings |
| |
|
| | msg = _get_invalid_paths_message(raw_tzpath) |
| |
|
| | warnings.warn( |
| | "Invalid paths specified in PYTHONTZPATH environment variable. " |
| | + msg, |
| | InvalidTZPathWarning, |
| | ) |
| |
|
| | return new_tzpath |
| |
|
| |
|
| | def _get_invalid_paths_message(tzpaths): |
| | invalid_paths = (path for path in tzpaths if not os.path.isabs(path)) |
| |
|
| | prefix = "\n " |
| | indented_str = prefix + prefix.join(invalid_paths) |
| |
|
| | return ( |
| | "Paths should be absolute but found the following relative paths:" |
| | + indented_str |
| | ) |
| |
|
| |
|
| | def find_tzfile(key): |
| | """Retrieve the path to a TZif file from a key.""" |
| | _validate_tzfile_path(key) |
| | for search_path in TZPATH: |
| | filepath = os.path.join(search_path, key) |
| | if os.path.isfile(filepath): |
| | return filepath |
| |
|
| | return None |
| |
|
| |
|
| | _TEST_PATH = os.path.normpath(os.path.join("_", "_"))[:-1] |
| |
|
| |
|
| | def _validate_tzfile_path(path, _base=_TEST_PATH): |
| | if os.path.isabs(path): |
| | raise ValueError( |
| | f"ZoneInfo keys may not be absolute paths, got: {path}" |
| | ) |
| |
|
| | |
| | |
| | |
| | |
| | new_path = os.path.normpath(path) |
| | if len(new_path) != len(path): |
| | raise ValueError( |
| | f"ZoneInfo keys must be normalized relative paths, got: {path}" |
| | ) |
| |
|
| | resolved = os.path.normpath(os.path.join(_base, new_path)) |
| | if not resolved.startswith(_base): |
| | raise ValueError( |
| | f"ZoneInfo keys must refer to subdirectories of TZPATH, got: {path}" |
| | ) |
| |
|
| |
|
| | del _TEST_PATH |
| |
|
| |
|
| | def available_timezones(): |
| | """Returns a set containing all available time zones. |
| | |
| | .. caution:: |
| | |
| | This may attempt to open a large number of files, since the best way to |
| | determine if a given file on the time zone search path is to open it |
| | and check for the "magic string" at the beginning. |
| | """ |
| | from importlib import resources |
| |
|
| | valid_zones = set() |
| |
|
| | |
| | |
| | try: |
| | with resources.open_text("tzdata", "zones") as f: |
| | for zone in f: |
| | zone = zone.strip() |
| | if zone: |
| | valid_zones.add(zone) |
| | except (ImportError, FileNotFoundError): |
| | pass |
| |
|
| | def valid_key(fpath): |
| | try: |
| | with open(fpath, "rb") as f: |
| | return f.read(4) == b"TZif" |
| | except Exception: |
| | return False |
| |
|
| | for tz_root in TZPATH: |
| | if not os.path.exists(tz_root): |
| | continue |
| |
|
| | for root, dirnames, files in os.walk(tz_root): |
| | if root == tz_root: |
| | |
| | |
| | if "right" in dirnames: |
| | dirnames.remove("right") |
| | if "posix" in dirnames: |
| | dirnames.remove("posix") |
| |
|
| | for file in files: |
| | fpath = os.path.join(root, file) |
| |
|
| | key = os.path.relpath(fpath, start=tz_root) |
| | if os.sep != "/": |
| | key = key.replace(os.sep, "/") |
| |
|
| | if not key or key in valid_zones: |
| | continue |
| |
|
| | if valid_key(fpath): |
| | valid_zones.add(key) |
| |
|
| | if "posixrules" in valid_zones: |
| | |
| | |
| | valid_zones.remove("posixrules") |
| |
|
| | return valid_zones |
| |
|
| |
|
| | class InvalidTZPathWarning(RuntimeWarning): |
| | """Warning raised if an invalid path is specified in PYTHONTZPATH.""" |
| |
|
| |
|
| | TZPATH = () |
| | reset_tzpath() |
| |
|