Files
dvc/dvc/utils/serialize/_common.py
T
skshetry 6df70d388e update pre-commit; add some more hooks (#8492)
* update pre-commit; add some more hooks

* Apply suggestions from code review
2022-10-31 21:04:11 +05:45

97 lines
2.3 KiB
Python

"""Common utilities for serialize."""
import os
from contextlib import contextmanager
from typing import (
TYPE_CHECKING,
Any,
Callable,
ContextManager,
Dict,
Protocol,
Union,
)
from funcy import reraise
from dvc.exceptions import DvcException
if TYPE_CHECKING:
from dvc.fs import FileSystem
from dvc.types import AnyPath
class DumperFn(Protocol):
def __call__(
self, path: "AnyPath", data: Any, fs: "FileSystem" = None
) -> Any:
...
class ModifierFn(Protocol):
def __call__(
self, path: "AnyPath", fs: "FileSystem" = None
) -> ContextManager[Dict]:
...
class LoaderFn(Protocol):
def __call__(self, path: "AnyPath", fs: "FileSystem" = None) -> Any:
...
ReadType = Union[bytes, None, str]
ParserFn = Callable[[ReadType, "AnyPath"], dict]
class ParseError(DvcException):
"""Errors while parsing files"""
def __init__(self, path: "AnyPath", message: str):
from dvc.utils import relpath
path = relpath(path)
self.path = path
super().__init__(f"unable to read: '{path}', {message}")
class EncodingError(ParseError):
"""We could not read a file with the given encoding"""
def __init__(self, path: "AnyPath", encoding: str):
self.encoding = encoding
super().__init__(path, f"is not valid {encoding}")
def _load_data(path: "AnyPath", parser: ParserFn, fs: "FileSystem" = None):
open_fn = fs.open if fs else open
encoding = "utf-8"
with open_fn(path, encoding=encoding) as fd: # type: ignore
with reraise(UnicodeDecodeError, EncodingError(path, encoding)):
return parser(fd.read(), path)
def _dump_data(
path,
data: Any,
dumper: DumperFn,
fs: "FileSystem" = None,
**dumper_args,
):
open_fn = fs.open if fs else open
with open_fn(path, "w+", encoding="utf-8") as fd: # type: ignore
dumper(data, fd, **dumper_args)
@contextmanager
def _modify_data(
path: "AnyPath",
parser: ParserFn,
dumper: DumperFn,
fs: "FileSystem" = None,
):
exists_fn = fs.exists if fs else os.path.exists
file_exists = exists_fn(path) # type: ignore
data = _load_data(path, parser=parser, fs=fs) if file_exists else {}
yield data
dumper(path, data, fs=fs)