lsst.obs.base  20.0.0-74-g0218c7a+7d276c6844
pexConfig.py
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1 # This file is part of daf_butler.
2 #
3 # Developed for the LSST Data Management System.
4 # This product includes software developed by the LSST Project
5 # (http://www.lsst.org).
6 # See the COPYRIGHT file at the top-level directory of this distribution
7 # for details of code ownership.
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21 
22 from __future__ import annotations
23 
24 __all__ = ("PexConfigFormatter", )
25 
26 import os.path
27 
28 from typing import (
29  Any,
30  Optional,
31  Type,
32 )
33 
34 from lsst.pex.config import Config
35 from lsst.daf.butler.formatters.file import FileFormatter
36 
37 
38 class PexConfigFormatter(FileFormatter):
39  """Interface for reading and writing pex.config.Config objects from disk.
40  """
41  extension = ".py"
42 
43  def _readFile(self, path: str, pytype: Optional[Type[Any]] = None) -> Any:
44  """Read a pex.config.Config instance from the given file.
45 
46  Parameters
47  ----------
48  path : `str`
49  Path to use to open the file.
50  pytype : `type`, optional
51  Class to use to read the config file.
52 
53  Returns
54  -------
55  data : `lsst.pex.config.Config`
56  Instance of class ``pytype`` read from config file. `None`
57  if the file could not be opened.
58  """
59  if not os.path.exists(path):
60  return None
61 
62  # Automatically determine the Config class from the serialized form
63  with open(path, "r") as fd:
64  config_py = fd.read()
65  return Config._fromPython(config_py)
66 
67  def _writeFile(self, inMemoryDataset: Any) -> None:
68  """Write the in memory dataset to file on disk.
69 
70  Parameters
71  ----------
72  inMemoryDataset : `object`
73  Object to serialize.
74 
75  Raises
76  ------
77  Exception
78  The file could not be written.
79  """
80  inMemoryDataset.save(self.fileDescriptor.location.path)
lsst.obs.base.formatters.pexConfig.PexConfigFormatter
Definition: pexConfig.py:38