cpython/Lib/plat-mac/plistlib.py

"""plistlib.py -- a tool to generate and parse MacOSX .plist files.

The PropertList (.plist) file format is a simple XML pickle supporting
basic object types, like dictionaries, lists, numbers and strings.
Usually the top level object is a dictionary.

To write out a plist file, use the writePlist(rootObject, pathOrFile)
function. 'rootObject' is the top level object, 'pathOrFile' is a
filename or a (writable) file object.

To parse a plist from a file, use the readPlist(pathOrFile)
function, with a file name or a (readable) file object as the only
argument. It returns the top level object (usually a dictionary).

Values can be strings, integers, floats, booleans, tuples, lists,
dictionaries, Data or Date objects. String values (including dictionary
keys) may be unicode strings -- they will be written out as UTF-8.

This module exports a class named Dict(), which allows you to easily
construct (nested) dicts using keyword arguments as well as accessing
values with attribute notation, where d.foo is equivalent to d["foo"].
Regular dictionaries work, too.

The <data> plist type is supported through the Data class. This is a
thin wrapper around a Python string.

The <date> plist data has (limited) support through the Date class.
(Warning: Dates are only supported if the PyXML package is installed.)

Generate Plist example:

    pl = Dict(
        aString="Doodah",
        aList=["A", "B", 12, 32.1, [1, 2, 3]],
        aFloat = 0.1,
        anInt = 728,
        aDict=Dict(
            anotherString="<hello & hi there!>",
            aUnicodeValue=u'M\xe4ssig, Ma\xdf',
            aTrueValue=True,
            aFalseValue=False,
        ),
        someData = Data("<binary gunk>"),
        someMoreData = Data("<lots of binary gunk>" * 10),
        aDate = Date(time.mktime(time.gmtime())),
    )
    # unicode keys are possible, but a little awkward to use:
    pl[u'\xc5benraa'] = "That was a unicode key."
    writePlist(pl, fileName)

Parse Plist example:

    pl = readPlist(pathOrFile)
    print pl.aKey  # same as pl["aKey"]


"""


__all__ = ["readPlist", "writePlist", "Plist", "Data", "Date", "Dict"]
# Note: the Plist class has been deprecated.


def readPlist(pathOrFile):
    """Read a .plist file. 'pathOrFile' may either be a file name or a
    (readable) file object. Return the unpacked root object (which
    usually is a dictionary).
    """
    didOpen = 0
    if isinstance(pathOrFile, (str, unicode)):
        pathOrFile = open(pathOrFile)
        didOpen = 1
    p = PlistParser()
    rootObject = p.parse(pathOrFile)
    if didOpen:
        pathOrFile.close()
    return rootObject


def writePlist(rootObject, pathOrFile):
    """Write 'rootObject' to a .plist file. 'pathOrFile' may either be a
    file name or a (writable) file object.
    """
    didOpen = 0
    if isinstance(pathOrFile, (str, unicode)):
        pathOrFile = open(pathOrFile, "w")
        didOpen = 1
    writer = PlistWriter(pathOrFile)
    writer.writeln("<plist version=\"1.0\">")
    writer.writeValue(rootObject)
    writer.writeln("</plist>")
    if didOpen:
        pathOrFile.close()


class DumbXMLWriter:

    def __init__(self, file, indentLevel=0, indent="\t"):
        self.file = file
        self.stack = []
        self.indentLevel = indentLevel
        self.indent = indent

    def beginElement(self, element):
        self.stack.append(element)
        self.writeln("<%s>" % element)
        self.indentLevel += 1

    def endElement(self, element):
        assert self.indentLevel > 0
        assert self.stack.pop() == element
        self.indentLevel -= 1
        self.writeln("</%s>" % element)

    def simpleElement(self, element, value=None):
        if value is not None:
            value = _escapeAndEncode(value)
            self.writeln("<%s>%s</%s>" % (element, value, element))
        else:
            self.writeln("<%s/>" % element)

    def writeln(self, line):
        if line:
            self.file.write(self.indentLevel * self.indent + line + "\n")
        else:
            self.file.write("\n")


import re
# Regex to strip all control chars, but for \t \n \r and \f
_controlStripper = re.compile(r"[\x00\x01\x02\x03\x04\x05\x06\x07\x08\x0b\x0e\x0f"
    "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f]")

def _escapeAndEncode(text):
    text = text.replace("\r\n", "\n")       # convert DOS line endings
    text = text.replace("\r", "\n")         # convert Mac line endings
    text = text.replace("&", "&amp;")       # escape '&'
    text = text.replace("<", "&lt;")        # escape '<'
    text = _controlStripper.sub("?", text)  # replace control chars with '?'
    return text.encode("utf-8")             # encode as UTF-8


PLISTHEADER = """\
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
"""

class PlistWriter(DumbXMLWriter):

    def __init__(self, file, indentLevel=0, indent="\t", writeHeader=1):
        if writeHeader:
            file.write(PLISTHEADER)
        DumbXMLWriter.__init__(self, file, indentLevel, indent)

    def writeValue(self, value):
        if isinstance(value, (str, unicode)):
            self.simpleElement("string", value)
        elif isinstance(value, bool):
            # must switch for bool before int, as bool is a
            # subclass of int...
            if value:
                self.simpleElement("true")
            else:
                self.simpleElement("false")
        elif isinstance(value, int):
            self.simpleElement("integer", str(value))
        elif isinstance(value, float):
            # should perhaps use repr() for better precision?
            self.simpleElement("real", str(value))
        elif isinstance(value, dict):
            self.writeDict(value)
        elif isinstance(value, Data):
            self.writeData(value)
        elif isinstance(value, Date):
            self.simpleElement("date", value.toString())
        elif isinstance(value, (tuple, list)):
            self.writeArray(value)
        else:
            raise TypeError("unsuported type: %s" % type(value))

    def writeData(self, data):
        self.beginElement("data")
        for line in data.asBase64().split("\n"):
            if line:
                self.writeln(line)
        self.endElement("data")

    def writeDict(self, d):
        self.beginElement("dict")
        items = d.items()
        items.sort()
        for key, value in items:
            if not isinstance(key, (str, unicode)):
                raise TypeError("keys must be strings")
            self.simpleElement("key", key)
            self.writeValue(value)
        self.endElement("dict")

    def writeArray(self, array):
        self.beginElement("array")
        for value in array:
            self.writeValue(value)
        self.endElement("array")


class Dict(dict):

    """Convenience dictionary subclass: it allows dict construction using
    keyword arguments (just like dict() in 2.3) as well as attribute notation
    to retrieve values, making d.foo equivalent to d["foo"].
    """

    def __new__(cls, **kwargs):
        self = dict.__new__(cls)
        self.update(kwargs)
        return self

    def __init__(self, **kwargs):
        self.update(kwargs)

    def __getattr__(self, attr):
        try:
            value = self[attr]
        except KeyError:
            raise AttributeError, attr
        return value

    def __setattr__(self, attr, value):
        self[attr] = value

    def __delattr__(self, attr):
        try:
            del self[attr]
        except KeyError:
            raise AttributeError, attr


class Plist(Dict):

    """This class has been deprecated! Use the Dict with readPlist() and
    writePlist() functions instead.
    """

    def fromFile(cls, pathOrFile):
        """Deprecated! Use the readPlist() function instead."""
        rootObject = readPlist(pathOrFile)
        plist = cls()
        plist.update(rootObject)
        return plist
    fromFile = classmethod(fromFile)

    def write(self, pathOrFile):
        """Deprecated! Use the writePlist() function instead."""
        writePlist(self, pathOrFile)


class Data:

    """Wrapper for binary data."""

    def __init__(self, data):
        self.data = data

    def fromBase64(cls, data):
        import base64
        return cls(base64.decodestring(data))
    fromBase64 = classmethod(fromBase64)

    def asBase64(self):
        import base64
        return base64.encodestring(self.data)

    def __cmp__(self, other):
        if isinstance(other, self.__class__):
            return cmp(self.data, other.data)
        elif isinstance(other, str):
            return cmp(self.data, other)
        else:
            return cmp(id(self), id(other))

    def __repr__(self):
        return "%s(%s)" % (self.__class__.__name__, repr(self.data))


class Date:

    """Primitive date wrapper, uses time floats internally, is agnostic
    about time zones.
    """

    def __init__(self, date):
        if isinstance(date, str):
            from xml.utils.iso8601 import parse
            date = parse(date)
        self.date = date

    def toString(self):
        from xml.utils.iso8601 import tostring
        return tostring(self.date)

    def __cmp__(self, other):
        if isinstance(other, self.__class__):
            return cmp(self.date, other.date)
        elif isinstance(other, (int, float)):
            return cmp(self.date, other)
        else:
            return cmp(id(self), id(other))

    def __repr__(self):
        return "%s(%s)" % (self.__class__.__name__, repr(self.toString()))


class PlistParser:

    def __init__(self):
        self.stack = []
        self.currentKey = None
        self.root = None

    def parse(self, file):
        from xml.parsers.expat import ParserCreate
        parser = ParserCreate()
        parser.StartElementHandler = self.handleBeginElement
        parser.EndElementHandler = self.handleEndElement
        parser.CharacterDataHandler = self.handleData
        parser.ParseFile(file)
        return self.root

    def handleBeginElement(self, element, attrs):
        self.data = []
        handler = getattr(self, "begin_" + element, None)
        if handler is not None:
            handler(attrs)

    def handleEndElement(self, element):
        handler = getattr(self, "end_" + element, None)
        if handler is not None:
            handler()

    def handleData(self, data):
        self.data.append(data)

    def addObject(self, value):
        if self.currentKey is not None:
            self.stack[-1][self.currentKey] = value
            self.currentKey = None
        elif not self.stack:
            # this is the root object
            self.root = value
        else:
            self.stack[-1].append(value)

    def getData(self):
        data = "".join(self.data)
        try:
            data = data.encode("ascii")
        except UnicodeError:
            pass
        self.data = []
        return data

    # element handlers

    def begin_dict(self, attrs):
        d = Dict()
        self.addObject(d)
        self.stack.append(d)
    def end_dict(self):
        self.stack.pop()

    def end_key(self):
        self.currentKey = self.getData()

    def begin_array(self, attrs):
        a = []
        self.addObject(a)
        self.stack.append(a)
    def end_array(self):
        self.stack.pop()

    def end_true(self):
        self.addObject(True)
    def end_false(self):
        self.addObject(False)
    def end_integer(self):
        self.addObject(int(self.getData()))
    def end_real(self):
        self.addObject(float(self.getData()))
    def end_string(self):
        self.addObject(self.getData())
    def end_data(self):
        self.addObject(Data.fromBase64(self.getData()))
    def end_date(self):
        self.addObject(Date(self.getData()))