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877 lines
28 KiB
877 lines
28 KiB
:mod:`xml.parsers.expat` --- Fast XML parsing using Expat
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=========================================================
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.. module:: xml.parsers.expat
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:synopsis: An interface to the Expat non-validating XML parser.
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.. moduleauthor:: Paul Prescod <paul@prescod.net>
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--------------
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.. Markup notes:
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Many of the attributes of the XMLParser objects are callbacks. Since
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signature information must be presented, these are described using the method
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directive. Since they are attributes which are set by client code, in-text
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references to these attributes should be marked using the :member: role.
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.. warning::
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The :mod:`pyexpat` module is not secure against maliciously
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constructed data. If you need to parse untrusted or unauthenticated data see
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:ref:`xml-vulnerabilities`.
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.. index:: single: Expat
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The :mod:`xml.parsers.expat` module is a Python interface to the Expat
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non-validating XML parser. The module provides a single extension type,
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:class:`xmlparser`, that represents the current state of an XML parser. After
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an :class:`xmlparser` object has been created, various attributes of the object
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can be set to handler functions. When an XML document is then fed to the
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parser, the handler functions are called for the character data and markup in
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the XML document.
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.. index:: module: pyexpat
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This module uses the :mod:`pyexpat` module to provide access to the Expat
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parser. Direct use of the :mod:`pyexpat` module is deprecated.
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This module provides one exception and one type object:
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.. exception:: ExpatError
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The exception raised when Expat reports an error. See section
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:ref:`expaterror-objects` for more information on interpreting Expat errors.
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.. exception:: error
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Alias for :exc:`ExpatError`.
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.. data:: XMLParserType
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The type of the return values from the :func:`ParserCreate` function.
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The :mod:`xml.parsers.expat` module contains two functions:
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.. function:: ErrorString(errno)
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Returns an explanatory string for a given error number *errno*.
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.. function:: ParserCreate(encoding=None, namespace_separator=None)
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Creates and returns a new :class:`xmlparser` object. *encoding*, if specified,
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must be a string naming the encoding used by the XML data. Expat doesn't
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support as many encodings as Python does, and its repertoire of encodings can't
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be extended; it supports UTF-8, UTF-16, ISO-8859-1 (Latin1), and ASCII. If
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*encoding* [1]_ is given it will override the implicit or explicit encoding of the
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document.
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Expat can optionally do XML namespace processing for you, enabled by providing a
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value for *namespace_separator*. The value must be a one-character string; a
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:exc:`ValueError` will be raised if the string has an illegal length (``None``
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is considered the same as omission). When namespace processing is enabled,
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element type names and attribute names that belong to a namespace will be
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expanded. The element name passed to the element handlers
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:attr:`StartElementHandler` and :attr:`EndElementHandler` will be the
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concatenation of the namespace URI, the namespace separator character, and the
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local part of the name. If the namespace separator is a zero byte (``chr(0)``)
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then the namespace URI and the local part will be concatenated without any
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separator.
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For example, if *namespace_separator* is set to a space character (``' '``) and
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the following document is parsed:
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.. code-block:: xml
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<?xml version="1.0"?>
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<root xmlns = "http://default-namespace.org/"
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xmlns:py = "http://www.python.org/ns/">
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<py:elem1 />
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<elem2 xmlns="" />
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</root>
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:attr:`StartElementHandler` will receive the following strings for each
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element::
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http://default-namespace.org/ root
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http://www.python.org/ns/ elem1
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elem2
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Due to limitations in the ``Expat`` library used by :mod:`pyexpat`,
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the :class:`xmlparser` instance returned can only be used to parse a single
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XML document. Call ``ParserCreate`` for each document to provide unique
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parser instances.
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.. seealso::
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`The Expat XML Parser <http://www.libexpat.org/>`_
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Home page of the Expat project.
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.. _xmlparser-objects:
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XMLParser Objects
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-----------------
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:class:`xmlparser` objects have the following methods:
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.. method:: xmlparser.Parse(data[, isfinal])
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Parses the contents of the string *data*, calling the appropriate handler
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functions to process the parsed data. *isfinal* must be true on the final call
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to this method; it allows the parsing of a single file in fragments,
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not the submission of multiple files.
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*data* can be the empty string at any time.
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.. method:: xmlparser.ParseFile(file)
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Parse XML data reading from the object *file*. *file* only needs to provide
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the ``read(nbytes)`` method, returning the empty string when there's no more
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data.
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.. method:: xmlparser.SetBase(base)
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Sets the base to be used for resolving relative URIs in system identifiers in
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declarations. Resolving relative identifiers is left to the application: this
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value will be passed through as the *base* argument to the
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:func:`ExternalEntityRefHandler`, :func:`NotationDeclHandler`, and
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:func:`UnparsedEntityDeclHandler` functions.
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.. method:: xmlparser.GetBase()
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Returns a string containing the base set by a previous call to :meth:`SetBase`,
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or ``None`` if :meth:`SetBase` hasn't been called.
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.. method:: xmlparser.GetInputContext()
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Returns the input data that generated the current event as a string. The data is
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in the encoding of the entity which contains the text. When called while an
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event handler is not active, the return value is ``None``.
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.. method:: xmlparser.ExternalEntityParserCreate(context[, encoding])
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Create a "child" parser which can be used to parse an external parsed entity
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referred to by content parsed by the parent parser. The *context* parameter
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should be the string passed to the :meth:`ExternalEntityRefHandler` handler
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function, described below. The child parser is created with the
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:attr:`ordered_attributes` and :attr:`specified_attributes` set to the values of
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this parser.
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.. method:: xmlparser.SetParamEntityParsing(flag)
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Control parsing of parameter entities (including the external DTD subset).
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Possible *flag* values are :const:`XML_PARAM_ENTITY_PARSING_NEVER`,
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:const:`XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE` and
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:const:`XML_PARAM_ENTITY_PARSING_ALWAYS`. Return true if setting the flag
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was successful.
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.. method:: xmlparser.UseForeignDTD([flag])
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Calling this with a true value for *flag* (the default) will cause Expat to call
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the :attr:`ExternalEntityRefHandler` with :const:`None` for all arguments to
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allow an alternate DTD to be loaded. If the document does not contain a
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document type declaration, the :attr:`ExternalEntityRefHandler` will still be
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called, but the :attr:`StartDoctypeDeclHandler` and
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:attr:`EndDoctypeDeclHandler` will not be called.
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Passing a false value for *flag* will cancel a previous call that passed a true
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value, but otherwise has no effect.
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This method can only be called before the :meth:`Parse` or :meth:`ParseFile`
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methods are called; calling it after either of those have been called causes
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:exc:`ExpatError` to be raised with the :attr:`code` attribute set to
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``errors.codes[errors.XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING]``.
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:class:`xmlparser` objects have the following attributes:
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.. attribute:: xmlparser.buffer_size
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The size of the buffer used when :attr:`buffer_text` is true.
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A new buffer size can be set by assigning a new integer value
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to this attribute.
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When the size is changed, the buffer will be flushed.
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.. attribute:: xmlparser.buffer_text
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Setting this to true causes the :class:`xmlparser` object to buffer textual
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content returned by Expat to avoid multiple calls to the
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:meth:`CharacterDataHandler` callback whenever possible. This can improve
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performance substantially since Expat normally breaks character data into chunks
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at every line ending. This attribute is false by default, and may be changed at
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any time.
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.. attribute:: xmlparser.buffer_used
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If :attr:`buffer_text` is enabled, the number of bytes stored in the buffer.
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These bytes represent UTF-8 encoded text. This attribute has no meaningful
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interpretation when :attr:`buffer_text` is false.
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.. attribute:: xmlparser.ordered_attributes
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Setting this attribute to a non-zero integer causes the attributes to be
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reported as a list rather than a dictionary. The attributes are presented in
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the order found in the document text. For each attribute, two list entries are
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presented: the attribute name and the attribute value. (Older versions of this
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module also used this format.) By default, this attribute is false; it may be
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changed at any time.
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.. attribute:: xmlparser.specified_attributes
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If set to a non-zero integer, the parser will report only those attributes which
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were specified in the document instance and not those which were derived from
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attribute declarations. Applications which set this need to be especially
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careful to use what additional information is available from the declarations as
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needed to comply with the standards for the behavior of XML processors. By
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default, this attribute is false; it may be changed at any time.
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The following attributes contain values relating to the most recent error
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encountered by an :class:`xmlparser` object, and will only have correct values
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once a call to :meth:`Parse` or :meth:`ParseFile` has raised an
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:exc:`xml.parsers.expat.ExpatError` exception.
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.. attribute:: xmlparser.ErrorByteIndex
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Byte index at which an error occurred.
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.. attribute:: xmlparser.ErrorCode
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Numeric code specifying the problem. This value can be passed to the
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:func:`ErrorString` function, or compared to one of the constants defined in the
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``errors`` object.
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.. attribute:: xmlparser.ErrorColumnNumber
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Column number at which an error occurred.
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.. attribute:: xmlparser.ErrorLineNumber
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Line number at which an error occurred.
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The following attributes contain values relating to the current parse location
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in an :class:`xmlparser` object. During a callback reporting a parse event they
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indicate the location of the first of the sequence of characters that generated
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the event. When called outside of a callback, the position indicated will be
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just past the last parse event (regardless of whether there was an associated
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callback).
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.. attribute:: xmlparser.CurrentByteIndex
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Current byte index in the parser input.
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.. attribute:: xmlparser.CurrentColumnNumber
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Current column number in the parser input.
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.. attribute:: xmlparser.CurrentLineNumber
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Current line number in the parser input.
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Here is the list of handlers that can be set. To set a handler on an
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:class:`xmlparser` object *o*, use ``o.handlername = func``. *handlername* must
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be taken from the following list, and *func* must be a callable object accepting
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the correct number of arguments. The arguments are all strings, unless
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otherwise stated.
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.. method:: xmlparser.XmlDeclHandler(version, encoding, standalone)
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Called when the XML declaration is parsed. The XML declaration is the
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(optional) declaration of the applicable version of the XML recommendation, the
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encoding of the document text, and an optional "standalone" declaration.
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*version* and *encoding* will be strings, and *standalone* will be ``1`` if the
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document is declared standalone, ``0`` if it is declared not to be standalone,
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or ``-1`` if the standalone clause was omitted. This is only available with
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Expat version 1.95.0 or newer.
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.. method:: xmlparser.StartDoctypeDeclHandler(doctypeName, systemId, publicId, has_internal_subset)
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Called when Expat begins parsing the document type declaration (``<!DOCTYPE
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...``). The *doctypeName* is provided exactly as presented. The *systemId* and
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*publicId* parameters give the system and public identifiers if specified, or
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``None`` if omitted. *has_internal_subset* will be true if the document
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contains and internal document declaration subset. This requires Expat version
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1.2 or newer.
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.. method:: xmlparser.EndDoctypeDeclHandler()
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Called when Expat is done parsing the document type declaration. This requires
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Expat version 1.2 or newer.
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.. method:: xmlparser.ElementDeclHandler(name, model)
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Called once for each element type declaration. *name* is the name of the
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element type, and *model* is a representation of the content model.
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.. method:: xmlparser.AttlistDeclHandler(elname, attname, type, default, required)
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Called for each declared attribute for an element type. If an attribute list
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declaration declares three attributes, this handler is called three times, once
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for each attribute. *elname* is the name of the element to which the
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declaration applies and *attname* is the name of the attribute declared. The
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attribute type is a string passed as *type*; the possible values are
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``'CDATA'``, ``'ID'``, ``'IDREF'``, ... *default* gives the default value for
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the attribute used when the attribute is not specified by the document instance,
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or ``None`` if there is no default value (``#IMPLIED`` values). If the
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attribute is required to be given in the document instance, *required* will be
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true. This requires Expat version 1.95.0 or newer.
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.. method:: xmlparser.StartElementHandler(name, attributes)
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Called for the start of every element. *name* is a string containing the
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element name, and *attributes* is the element attributes. If
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:attr:`ordered_attributes` is true, this is a list (see
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:attr:`ordered_attributes` for a full description). Otherwise it's a
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dictionary mapping names to values.
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.. method:: xmlparser.EndElementHandler(name)
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Called for the end of every element.
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.. method:: xmlparser.ProcessingInstructionHandler(target, data)
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Called for every processing instruction.
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.. method:: xmlparser.CharacterDataHandler(data)
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Called for character data. This will be called for normal character data, CDATA
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marked content, and ignorable whitespace. Applications which must distinguish
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these cases can use the :attr:`StartCdataSectionHandler`,
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:attr:`EndCdataSectionHandler`, and :attr:`ElementDeclHandler` callbacks to
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collect the required information.
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.. method:: xmlparser.UnparsedEntityDeclHandler(entityName, base, systemId, publicId, notationName)
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Called for unparsed (NDATA) entity declarations. This is only present for
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version 1.2 of the Expat library; for more recent versions, use
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:attr:`EntityDeclHandler` instead. (The underlying function in the Expat
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library has been declared obsolete.)
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.. method:: xmlparser.EntityDeclHandler(entityName, is_parameter_entity, value, base, systemId, publicId, notationName)
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Called for all entity declarations. For parameter and internal entities,
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*value* will be a string giving the declared contents of the entity; this will
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be ``None`` for external entities. The *notationName* parameter will be
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``None`` for parsed entities, and the name of the notation for unparsed
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entities. *is_parameter_entity* will be true if the entity is a parameter entity
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or false for general entities (most applications only need to be concerned with
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general entities). This is only available starting with version 1.95.0 of the
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Expat library.
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.. method:: xmlparser.NotationDeclHandler(notationName, base, systemId, publicId)
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Called for notation declarations. *notationName*, *base*, and *systemId*, and
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*publicId* are strings if given. If the public identifier is omitted,
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*publicId* will be ``None``.
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.. method:: xmlparser.StartNamespaceDeclHandler(prefix, uri)
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Called when an element contains a namespace declaration. Namespace declarations
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are processed before the :attr:`StartElementHandler` is called for the element
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on which declarations are placed.
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.. method:: xmlparser.EndNamespaceDeclHandler(prefix)
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Called when the closing tag is reached for an element that contained a
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namespace declaration. This is called once for each namespace declaration on
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the element in the reverse of the order for which the
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:attr:`StartNamespaceDeclHandler` was called to indicate the start of each
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namespace declaration's scope. Calls to this handler are made after the
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corresponding :attr:`EndElementHandler` for the end of the element.
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.. method:: xmlparser.CommentHandler(data)
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Called for comments. *data* is the text of the comment, excluding the leading
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``'<!-``\ ``-'`` and trailing ``'-``\ ``->'``.
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.. method:: xmlparser.StartCdataSectionHandler()
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Called at the start of a CDATA section. This and :attr:`EndCdataSectionHandler`
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are needed to be able to identify the syntactical start and end for CDATA
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sections.
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.. method:: xmlparser.EndCdataSectionHandler()
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Called at the end of a CDATA section.
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.. method:: xmlparser.DefaultHandler(data)
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Called for any characters in the XML document for which no applicable handler
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has been specified. This means characters that are part of a construct which
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could be reported, but for which no handler has been supplied.
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.. method:: xmlparser.DefaultHandlerExpand(data)
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This is the same as the :func:`DefaultHandler`, but doesn't inhibit expansion
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of internal entities. The entity reference will not be passed to the default
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handler.
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.. method:: xmlparser.NotStandaloneHandler()
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Called if the XML document hasn't been declared as being a standalone document.
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This happens when there is an external subset or a reference to a parameter
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entity, but the XML declaration does not set standalone to ``yes`` in an XML
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declaration. If this handler returns ``0``, then the parser will raise an
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:const:`XML_ERROR_NOT_STANDALONE` error. If this handler is not set, no
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exception is raised by the parser for this condition.
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.. method:: xmlparser.ExternalEntityRefHandler(context, base, systemId, publicId)
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Called for references to external entities. *base* is the current base, as set
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by a previous call to :meth:`SetBase`. The public and system identifiers,
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*systemId* and *publicId*, are strings if given; if the public identifier is not
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given, *publicId* will be ``None``. The *context* value is opaque and should
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only be used as described below.
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For external entities to be parsed, this handler must be implemented. It is
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responsible for creating the sub-parser using
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``ExternalEntityParserCreate(context)``, initializing it with the appropriate
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callbacks, and parsing the entity. This handler should return an integer; if it
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returns ``0``, the parser will raise an
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:const:`XML_ERROR_EXTERNAL_ENTITY_HANDLING` error, otherwise parsing will
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continue.
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If this handler is not provided, external entities are reported by the
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:attr:`DefaultHandler` callback, if provided.
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.. _expaterror-objects:
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ExpatError Exceptions
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---------------------
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.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
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:exc:`ExpatError` exceptions have a number of interesting attributes:
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.. attribute:: ExpatError.code
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Expat's internal error number for the specific error. The
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:data:`errors.messages <xml.parsers.expat.errors.messages>` dictionary maps
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these error numbers to Expat's error messages. For example::
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from xml.parsers.expat import ParserCreate, ExpatError, errors
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p = ParserCreate()
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try:
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p.Parse(some_xml_document)
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except ExpatError as err:
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print("Error:", errors.messages[err.code])
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The :mod:`~xml.parsers.expat.errors` module also provides error message
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constants and a dictionary :data:`~xml.parsers.expat.errors.codes` mapping
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these messages back to the error codes, see below.
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.. attribute:: ExpatError.lineno
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Line number on which the error was detected. The first line is numbered ``1``.
|
|
|
|
|
|
.. attribute:: ExpatError.offset
|
|
|
|
Character offset into the line where the error occurred. The first column is
|
|
numbered ``0``.
|
|
|
|
|
|
.. _expat-example:
|
|
|
|
Example
|
|
-------
|
|
|
|
The following program defines three handlers that just print out their
|
|
arguments. ::
|
|
|
|
import xml.parsers.expat
|
|
|
|
# 3 handler functions
|
|
def start_element(name, attrs):
|
|
print('Start element:', name, attrs)
|
|
def end_element(name):
|
|
print('End element:', name)
|
|
def char_data(data):
|
|
print('Character data:', repr(data))
|
|
|
|
p = xml.parsers.expat.ParserCreate()
|
|
|
|
p.StartElementHandler = start_element
|
|
p.EndElementHandler = end_element
|
|
p.CharacterDataHandler = char_data
|
|
|
|
p.Parse("""<?xml version="1.0"?>
|
|
<parent id="top"><child1 name="paul">Text goes here</child1>
|
|
<child2 name="fred">More text</child2>
|
|
</parent>""", 1)
|
|
|
|
The output from this program is::
|
|
|
|
Start element: parent {'id': 'top'}
|
|
Start element: child1 {'name': 'paul'}
|
|
Character data: 'Text goes here'
|
|
End element: child1
|
|
Character data: '\n'
|
|
Start element: child2 {'name': 'fred'}
|
|
Character data: 'More text'
|
|
End element: child2
|
|
Character data: '\n'
|
|
End element: parent
|
|
|
|
|
|
.. _expat-content-models:
|
|
|
|
Content Model Descriptions
|
|
--------------------------
|
|
|
|
.. module:: xml.parsers.expat.model
|
|
|
|
.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
|
|
|
|
Content models are described using nested tuples. Each tuple contains four
|
|
values: the type, the quantifier, the name, and a tuple of children. Children
|
|
are simply additional content model descriptions.
|
|
|
|
The values of the first two fields are constants defined in the
|
|
:mod:`xml.parsers.expat.model` module. These constants can be collected in two
|
|
groups: the model type group and the quantifier group.
|
|
|
|
The constants in the model type group are:
|
|
|
|
|
|
.. data:: XML_CTYPE_ANY
|
|
:noindex:
|
|
|
|
The element named by the model name was declared to have a content model of
|
|
``ANY``.
|
|
|
|
|
|
.. data:: XML_CTYPE_CHOICE
|
|
:noindex:
|
|
|
|
The named element allows a choice from a number of options; this is used for
|
|
content models such as ``(A | B | C)``.
|
|
|
|
|
|
.. data:: XML_CTYPE_EMPTY
|
|
:noindex:
|
|
|
|
Elements which are declared to be ``EMPTY`` have this model type.
|
|
|
|
|
|
.. data:: XML_CTYPE_MIXED
|
|
:noindex:
|
|
|
|
|
|
.. data:: XML_CTYPE_NAME
|
|
:noindex:
|
|
|
|
|
|
.. data:: XML_CTYPE_SEQ
|
|
:noindex:
|
|
|
|
Models which represent a series of models which follow one after the other are
|
|
indicated with this model type. This is used for models such as ``(A, B, C)``.
|
|
|
|
The constants in the quantifier group are:
|
|
|
|
|
|
.. data:: XML_CQUANT_NONE
|
|
:noindex:
|
|
|
|
No modifier is given, so it can appear exactly once, as for ``A``.
|
|
|
|
|
|
.. data:: XML_CQUANT_OPT
|
|
:noindex:
|
|
|
|
The model is optional: it can appear once or not at all, as for ``A?``.
|
|
|
|
|
|
.. data:: XML_CQUANT_PLUS
|
|
:noindex:
|
|
|
|
The model must occur one or more times (like ``A+``).
|
|
|
|
|
|
.. data:: XML_CQUANT_REP
|
|
:noindex:
|
|
|
|
The model must occur zero or more times, as for ``A*``.
|
|
|
|
|
|
.. _expat-errors:
|
|
|
|
Expat error constants
|
|
---------------------
|
|
|
|
.. module:: xml.parsers.expat.errors
|
|
|
|
The following constants are provided in the :mod:`xml.parsers.expat.errors`
|
|
module. These constants are useful in interpreting some of the attributes of
|
|
the :exc:`ExpatError` exception objects raised when an error has occurred.
|
|
Since for backwards compatibility reasons, the constants' value is the error
|
|
*message* and not the numeric error *code*, you do this by comparing its
|
|
:attr:`code` attribute with
|
|
:samp:`errors.codes[errors.XML_ERROR_{CONSTANT_NAME}]`.
|
|
|
|
The ``errors`` module has the following attributes:
|
|
|
|
.. data:: codes
|
|
|
|
A dictionary mapping numeric error codes to their string descriptions.
|
|
|
|
.. versionadded:: 3.2
|
|
|
|
|
|
.. data:: messages
|
|
|
|
A dictionary mapping string descriptions to their error codes.
|
|
|
|
.. versionadded:: 3.2
|
|
|
|
|
|
.. data:: XML_ERROR_ASYNC_ENTITY
|
|
|
|
|
|
.. data:: XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF
|
|
|
|
An entity reference in an attribute value referred to an external entity instead
|
|
of an internal entity.
|
|
|
|
|
|
.. data:: XML_ERROR_BAD_CHAR_REF
|
|
|
|
A character reference referred to a character which is illegal in XML (for
|
|
example, character ``0``, or '``�``').
|
|
|
|
|
|
.. data:: XML_ERROR_BINARY_ENTITY_REF
|
|
|
|
An entity reference referred to an entity which was declared with a notation, so
|
|
cannot be parsed.
|
|
|
|
|
|
.. data:: XML_ERROR_DUPLICATE_ATTRIBUTE
|
|
|
|
An attribute was used more than once in a start tag.
|
|
|
|
|
|
.. data:: XML_ERROR_INCORRECT_ENCODING
|
|
|
|
|
|
.. data:: XML_ERROR_INVALID_TOKEN
|
|
|
|
Raised when an input byte could not properly be assigned to a character; for
|
|
example, a NUL byte (value ``0``) in a UTF-8 input stream.
|
|
|
|
|
|
.. data:: XML_ERROR_JUNK_AFTER_DOC_ELEMENT
|
|
|
|
Something other than whitespace occurred after the document element.
|
|
|
|
|
|
.. data:: XML_ERROR_MISPLACED_XML_PI
|
|
|
|
An XML declaration was found somewhere other than the start of the input data.
|
|
|
|
|
|
.. data:: XML_ERROR_NO_ELEMENTS
|
|
|
|
The document contains no elements (XML requires all documents to contain exactly
|
|
one top-level element)..
|
|
|
|
|
|
.. data:: XML_ERROR_NO_MEMORY
|
|
|
|
Expat was not able to allocate memory internally.
|
|
|
|
|
|
.. data:: XML_ERROR_PARAM_ENTITY_REF
|
|
|
|
A parameter entity reference was found where it was not allowed.
|
|
|
|
|
|
.. data:: XML_ERROR_PARTIAL_CHAR
|
|
|
|
An incomplete character was found in the input.
|
|
|
|
|
|
.. data:: XML_ERROR_RECURSIVE_ENTITY_REF
|
|
|
|
An entity reference contained another reference to the same entity; possibly via
|
|
a different name, and possibly indirectly.
|
|
|
|
|
|
.. data:: XML_ERROR_SYNTAX
|
|
|
|
Some unspecified syntax error was encountered.
|
|
|
|
|
|
.. data:: XML_ERROR_TAG_MISMATCH
|
|
|
|
An end tag did not match the innermost open start tag.
|
|
|
|
|
|
.. data:: XML_ERROR_UNCLOSED_TOKEN
|
|
|
|
Some token (such as a start tag) was not closed before the end of the stream or
|
|
the next token was encountered.
|
|
|
|
|
|
.. data:: XML_ERROR_UNDEFINED_ENTITY
|
|
|
|
A reference was made to an entity which was not defined.
|
|
|
|
|
|
.. data:: XML_ERROR_UNKNOWN_ENCODING
|
|
|
|
The document encoding is not supported by Expat.
|
|
|
|
|
|
.. data:: XML_ERROR_UNCLOSED_CDATA_SECTION
|
|
|
|
A CDATA marked section was not closed.
|
|
|
|
|
|
.. data:: XML_ERROR_EXTERNAL_ENTITY_HANDLING
|
|
|
|
|
|
.. data:: XML_ERROR_NOT_STANDALONE
|
|
|
|
The parser determined that the document was not "standalone" though it declared
|
|
itself to be in the XML declaration, and the :attr:`NotStandaloneHandler` was
|
|
set and returned ``0``.
|
|
|
|
|
|
.. data:: XML_ERROR_UNEXPECTED_STATE
|
|
|
|
|
|
.. data:: XML_ERROR_ENTITY_DECLARED_IN_PE
|
|
|
|
|
|
.. data:: XML_ERROR_FEATURE_REQUIRES_XML_DTD
|
|
|
|
An operation was requested that requires DTD support to be compiled in, but
|
|
Expat was configured without DTD support. This should never be reported by a
|
|
standard build of the :mod:`xml.parsers.expat` module.
|
|
|
|
|
|
.. data:: XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING
|
|
|
|
A behavioral change was requested after parsing started that can only be changed
|
|
before parsing has started. This is (currently) only raised by
|
|
:meth:`UseForeignDTD`.
|
|
|
|
|
|
.. data:: XML_ERROR_UNBOUND_PREFIX
|
|
|
|
An undeclared prefix was found when namespace processing was enabled.
|
|
|
|
|
|
.. data:: XML_ERROR_UNDECLARING_PREFIX
|
|
|
|
The document attempted to remove the namespace declaration associated with a
|
|
prefix.
|
|
|
|
|
|
.. data:: XML_ERROR_INCOMPLETE_PE
|
|
|
|
A parameter entity contained incomplete markup.
|
|
|
|
|
|
.. data:: XML_ERROR_XML_DECL
|
|
|
|
The document contained no document element at all.
|
|
|
|
|
|
.. data:: XML_ERROR_TEXT_DECL
|
|
|
|
There was an error parsing a text declaration in an external entity.
|
|
|
|
|
|
.. data:: XML_ERROR_PUBLICID
|
|
|
|
Characters were found in the public id that are not allowed.
|
|
|
|
|
|
.. data:: XML_ERROR_SUSPENDED
|
|
|
|
The requested operation was made on a suspended parser, but isn't allowed. This
|
|
includes attempts to provide additional input or to stop the parser.
|
|
|
|
|
|
.. data:: XML_ERROR_NOT_SUSPENDED
|
|
|
|
An attempt to resume the parser was made when the parser had not been suspended.
|
|
|
|
|
|
.. data:: XML_ERROR_ABORTED
|
|
|
|
This should not be reported to Python applications.
|
|
|
|
|
|
.. data:: XML_ERROR_FINISHED
|
|
|
|
The requested operation was made on a parser which was finished parsing input,
|
|
but isn't allowed. This includes attempts to provide additional input or to
|
|
stop the parser.
|
|
|
|
|
|
.. data:: XML_ERROR_SUSPEND_PE
|
|
|
|
|
|
.. rubric:: Footnotes
|
|
|
|
.. [1] The encoding string included in XML output should conform to the
|
|
appropriate standards. For example, "UTF-8" is valid, but "UTF8" is
|
|
not. See https://www.w3.org/TR/2006/REC-xml11-20060816/#NT-EncodingDecl
|
|
and https://www.iana.org/assignments/character-sets/character-sets.xhtml.
|
|
|