Coverage for python / lsst / daf / butler / formatters / pickle.py: 0%

1# This file is part of daf_butler. 

2# 

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14# 

15# This program is free software: you can redistribute it and/or modify 

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27 

28"""Formatter associated with Python pickled objects.""" 

29 

30from __future__ import annotations 

31 

32__all__ = ("PickleFormatter",) 

33 

34import pickle 

35from typing import Any 

36 

37from lsst.resources import ResourcePath 

38 

39from .typeless import TypelessFormatter 

40 

41 

42class PickleFormatter(TypelessFormatter): 

43 """Interface for reading and writing Python objects to and from pickle 

44 files. 

45 """ 

46 

47 default_extension = ".pickle" 

48 unsupported_parameters = None 

49 can_read_from_uri = True 

50 

51 def read_from_uri(self, uri: ResourcePath, component: str | None = None, expected_size: int = -1) -> Any: 

52 # Read the pickle file directly from the resource into memory. 

53 try: 

54 data = pickle.loads(uri.read()) 

55 except pickle.PicklingError: 

56 data = None 

57 

58 return data 

59 

60 def to_bytes(self, in_memory_dataset: Any) -> bytes: 

61 return pickle.dumps(in_memory_dataset, protocol=-1)