14.5. plistlib — Generate and parse Mac OS X .plist files

Source code: Lib/plistlib.py

This module provides an interface for reading and writing the “property list” files used mainly by Mac OS X and 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 dump() and load() functions.

To work with plist data in bytes objects, use dumps() and loads().

Values can be strings, integers, floats, booleans, tuples, lists, dictionaries (but only with string keys), Data, bytes, bytesarray or datetime.datetime objects.

This module defines the following functions:

plistlib.load(fp, *, fmt=None, use_builtin_types=True, 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:

• None: Autodetect the file format
• FMT_XML: XML file format
• FMT_BINARY: Binary plist format

If use_builtin_types is true (the default) binary data will be returned as instances of bytes, otherwise it is returned as instances of Data.

The dict_type is the type used for dictionaries that are read from the plist file. The exact structure of the plist can be recovered by using collections.OrderedDict (although the order of keys shouldn’t be important in plist files).

XML data for the FMT_XML format is parsed using the Expat parser from 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 InvalidFileException when the file cannot be parsed.

New in version 3.4.

plistlib.loads(data, *, fmt=None, use_builtin_types=True, dict_type=dict)

Load a plist from a bytes object. See load() for an explanation of the keyword arguments.

New in version 3.4.

plistlib.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:

• FMT_XML: XML formatted plist file
• 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 TypeError when a key of a dictionary is not a string, otherwise such keys are skipped.

A TypeError will be raised if the object is of an unsupported type or a container that contains objects of unsupported types.

An OverflowError will be raised for integer values that cannot be represented in (binary) plist files.

New in version 3.4.

plistlib.dumps(value, *, fmt=FMT_XML, sort_keys=True, skipkeys=False)

Return value as a plist-formatted bytes object. See the documentation for dump() for an explanation of the keyword arguments of this function.

New in version 3.4.

The following functions are deprecated:

plistlib.readPlist(pathOrFile)

Read a plist file. pathOrFile may be either a file name or a (readable and binary) file object. Returns the unpacked root object (which usually is a dictionary).

This function calls load() to do the actual work, see the documentation of that function for an explanation of the keyword arguments.

Note

Dict values in the result have a __getattr__ method that defers to __getitem_. This means that you can use attribute access to access items of these dictionaries.

Deprecated since version 3.4: Use load() instead.

plistlib.writePlist(rootObject, pathOrFile)

Write rootObject to an XML plist file. pathOrFile may be either a file name or a (writable and binary) file object

Deprecated since version 3.4: Use dump() instead.

plistlib.readPlistFromBytes(data)

Read a plist data from a bytes object. Return the root object.

See load() for a description of the keyword arguments.

Note

Dict values in the result have a __getattr__ method that defers to __getitem_. This means that you can use attribute access to access items of these dictionaries.

Deprecated since version 3.4: Use loads() instead.

plistlib.writePlistToBytes(rootObject)

Return rootObject as an XML plist-formatted bytes object.

Deprecated since version 3.4: Use dumps() instead.

The following classes are available:

Dict([dict]):

Return an extended mapping object with the same value as dictionary dict.

This class is a subclass of dict where attribute access can be used to access items. That is, aDict.key is the same as aDict['key'] for getting, setting and deleting items in the mapping.

Deprecated since version 3.0.

class plistlib.Data(data)

Return a “data” wrapper object around the bytes object data. This is used in functions converting from/to plists to represent the <data> type available in plists.

It has one attribute, data, that can be used to retrieve the Python bytes object stored in it.

Deprecated since version 3.4: Use a bytes object instead.

The following constants are available:

plistlib.FMT_XML

The XML format for plist files.

New in version 3.4.

plistlib.FMT_BINARY

The binary format for plist files

New in version 3.4.

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)

with open(fileName, 'rb') as fp:
    pl = load(fp)
print(pl["aKey"])