cpython/Doc/library/plistlib.rst

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:mod:`plistlib` --- Generate and parse Apple ``.plist`` files
=============================================================
.. module:: plistlib
:synopsis: Generate and parse Apple plist files.
.. moduleauthor:: Jack Jansen
.. sectionauthor:: Georg Brandl <georg@python.org>
.. (harvested from docstrings in the original file)
**Source code:** :source:`Lib/plistlib.py`
.. index::
pair: plist; file
single: property list
--------------
This module provides an interface for reading and writing the "property list"
files used by Apple, primarily on macOS and iOS. This module supports both binary
and XML plist files.
The property list (``.plist``) file format is a simple serialization supporting
basic object types, like dictionaries, lists, numbers and strings. Usually the
top level object is a dictionary.
To write out and to parse a plist file, use the :func:`dump` and
:func:`load` functions.
To work with plist data in bytes objects, use :func:`dumps`
and :func:`loads`.
Values can be strings, integers, floats, booleans, tuples, lists, dictionaries
(but only with string keys), :class:`bytes`, :class:`bytearray`
or :class:`datetime.datetime` objects.
.. versionchanged:: 3.4
New API, old API deprecated. Support for binary format plists added.
.. versionchanged:: 3.8
Support added for reading and writing :class:`UID` tokens in binary plists as used
by NSKeyedArchiver and NSKeyedUnarchiver.
.. versionchanged:: 3.9
Old API removed.
.. seealso::
`PList manual page <https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/PropertyLists/>`_
Apple's documentation of the file format.
This module defines the following functions:
.. function:: load(fp, \*, fmt=None, dict_type=dict)
Read a plist file. *fp* should be a readable and binary file object.
Return the unpacked root object (which usually is a
dictionary).
The *fmt* is the format of the file and the following values are valid:
* :data:`None`: Autodetect the file format
* :data:`FMT_XML`: XML file format
* :data:`FMT_BINARY`: Binary plist format
The *dict_type* is the type used for dictionaries that are read from the
plist file.
XML data for the :data:`FMT_XML` format is parsed using the Expat parser
from :mod:`xml.parsers.expat` -- see its documentation for possible
exceptions on ill-formed XML. Unknown elements will simply be ignored
by the plist parser.
The parser for the binary format raises :exc:`InvalidFileException`
when the file cannot be parsed.
.. versionadded:: 3.4
.. function:: loads(data, \*, fmt=None, dict_type=dict)
Load a plist from a bytes object. See :func:`load` for an explanation of
the keyword arguments.
.. versionadded:: 3.4
.. function:: dump(value, fp, \*, fmt=FMT_XML, sort_keys=True, skipkeys=False)
Write *value* to a plist file. *Fp* should be a writable, binary
file object.
The *fmt* argument specifies the format of the plist file and can be
one of the following values:
* :data:`FMT_XML`: XML formatted plist file
* :data:`FMT_BINARY`: Binary formatted plist file
When *sort_keys* is true (the default) the keys for dictionaries will be
written to the plist in sorted order, otherwise they will be written in
the iteration order of the dictionary.
When *skipkeys* is false (the default) the function raises :exc:`TypeError`
when a key of a dictionary is not a string, otherwise such keys are skipped.
A :exc:`TypeError` will be raised if the object is of an unsupported type or
a container that contains objects of unsupported types.
An :exc:`OverflowError` will be raised for integer values that cannot
be represented in (binary) plist files.
.. versionadded:: 3.4
.. function:: dumps(value, \*, fmt=FMT_XML, sort_keys=True, skipkeys=False)
Return *value* as a plist-formatted bytes object. See
the documentation for :func:`dump` for an explanation of the keyword
arguments of this function.
.. versionadded:: 3.4
The following classes are available:
.. class:: UID(data)
Wraps an :class:`int`. This is used when reading or writing NSKeyedArchiver
encoded data, which contains UID (see PList manual).
It has one attribute, :attr:`data`, which can be used to retrieve the int value
of the UID. :attr:`data` must be in the range `0 <= data < 2**64`.
.. versionadded:: 3.8
The following constants are available:
.. data:: FMT_XML
The XML format for plist files.
.. versionadded:: 3.4
.. data:: FMT_BINARY
The binary format for plist files
.. versionadded:: 3.4
Examples
--------
Generating a plist::
pl = dict(
aString = "Doodah",
aList = ["A", "B", 12, 32.1, [1, 2, 3]],
aFloat = 0.1,
anInt = 728,
aDict = dict(
anotherString = "<hello & hi there!>",
aThirdString = "M\xe4ssig, Ma\xdf",
aTrueValue = True,
aFalseValue = False,
),
someData = b"<binary gunk>",
someMoreData = b"<lots of binary gunk>" * 10,
aDate = datetime.datetime.fromtimestamp(time.mktime(time.gmtime())),
)
with open(fileName, 'wb') as fp:
dump(pl, fp)
Parsing a plist::
with open(fileName, 'rb') as fp:
pl = load(fp)
print(pl["aKey"])