html5lib
========
.. image:: https://travis-ci.org/html5lib/html5lib-python.png?branch=master
:target: https://travis-ci.org/html5lib/html5lib-python
html5lib is a pure-python library for parsing HTML. It is designed to
conform to the WHATWG HTML specification, as is implemented by all major
web browsers.
Usage
-----
Simple usage follows this pattern:
.. code-block:: python
import html5lib
with open("mydocument.html", "rb") as f:
document = html5lib.parse(f)
or:
.. code-block:: python
import html5lib
document = html5lib.parse("
Hello World!")
By default, the ``document`` will be an ``xml.etree`` element instance.
Whenever possible, html5lib chooses the accelerated ``ElementTree``
implementation (i.e. ``xml.etree.cElementTree`` on Python 2.x).
Two other tree types are supported: ``xml.dom.minidom`` and
``lxml.etree``. To use an alternative format, specify the name of
a treebuilder:
.. code-block:: python
import html5lib
with open("mydocument.html", "rb") as f:
lxml_etree_document = html5lib.parse(f, treebuilder="lxml")
When using with ``urllib2`` (Python 2), the charset from HTTP should be
pass into html5lib as follows:
.. code-block:: python
from contextlib import closing
from urllib2 import urlopen
import html5lib
with closing(urlopen("http://example.com/")) as f:
document = html5lib.parse(f, transport_encoding=f.info().getparam("charset"))
When using with ``urllib.request`` (Python 3), the charset from HTTP
should be pass into html5lib as follows:
.. code-block:: python
from urllib.request import urlopen
import html5lib
with urlopen("http://example.com/") as f:
document = html5lib.parse(f, transport_encoding=f.info().get_content_charset())
To have more control over the parser, create a parser object explicitly.
For instance, to make the parser raise exceptions on parse errors, use:
.. code-block:: python
import html5lib
with open("mydocument.html", "rb") as f:
parser = html5lib.HTMLParser(strict=True)
document = parser.parse(f)
When you're instantiating parser objects explicitly, pass a treebuilder
class as the ``tree`` keyword argument to use an alternative document
format:
.. code-block:: python
import html5lib
parser = html5lib.HTMLParser(tree=html5lib.getTreeBuilder("dom"))
minidom_document = parser.parse("
Hello World!")
More documentation is available at https://html5lib.readthedocs.io/.
Installation
------------
html5lib works on CPython 2.7+, CPython 3.3+ and PyPy. To install it,
use:
.. code-block:: bash
$ pip install html5lib
Optional Dependencies
---------------------
The following third-party libraries may be used for additional
functionality:
- ``datrie`` can be used under CPython to improve parsing performance
(though in almost all cases the improvement is marginal);
- ``lxml`` is supported as a tree format (for both building and
walking) under CPython (but *not* PyPy where it is known to cause
segfaults);
- ``genshi`` has a treewalker (but not builder); and
- ``chardet`` can be used as a fallback when character encoding cannot
be determined.
Bugs
----
Please report any bugs on the `issue tracker
`_.
Tests
-----
Unit tests require the ``pytest`` and ``mock`` libraries and can be
run using the ``py.test`` command in the root directory.
Test data are contained in a separate `html5lib-tests
`_ repository and included
as a submodule, thus for git checkouts they must be initialized::
$ git submodule init
$ git submodule update
If you have all compatible Python implementations available on your
system, you can run tests on all of them using the ``tox`` utility,
which can be found on PyPI.
Questions?
----------
There's a mailing list available for support on Google Groups,
`html5lib-discuss `_,
though you may get a quicker response asking on IRC in `#whatwg on
irc.freenode.net `_.
Change Log
----------
1.0.1
~~~~~
Released on December 7, 2017
Breaking changes:
* Drop support for Python 2.6. (#330) (Thank you, Hugo, Will Kahn-Greene!)
* Remove ``utils/spider.py`` (#353) (Thank you, Jon Dufresne!)
Features:
* Improve documentation. (#300, #307) (Thank you, Jon Dufresne, Tom Most,
Will Kahn-Greene!)
* Add iframe seamless boolean attribute. (Thank you, Ritwik Gupta!)
* Add itemscope as a boolean attribute. (#194) (Thank you, Jonathan Vanasco!)
* Support Python 3.6. (#333) (Thank you, Jon Dufresne!)
* Add CI support for Windows using AppVeyor. (Thank you, John Vandenberg!)
* Improve testing and CI and add code coverage (#323, #334), (Thank you, Jon
Dufresne, John Vandenberg, Geoffrey Sneddon, Will Kahn-Greene!)
* Semver-compliant version number.
Bug fixes:
* Add support for setuptools < 18.5 to support environment markers. (Thank you,
John Vandenberg!)
* Add explicit dependency for six >= 1.9. (Thank you, Eric Amorde!)
* Fix regexes to work with Python 3.7 regex adjustments. (#318, #379) (Thank
you, Benedikt Morbach, Ville Skyttä, Mark Vasilkov!)
* Fix alphabeticalattributes filter namespace bug. (#324) (Thank you, Will
Kahn-Greene!)
* Include license file in generated wheel package. (#350) (Thank you, Jon
Dufresne!)
* Fix annotation-xml typo. (#339) (Thank you, Will Kahn-Greene!)
* Allow uppercase hex chararcters in CSS colour check. (#377) (Thank you,
Komal Dembla, Hugo!)
1.0
~~~
Released and unreleased on December 7, 2017. Badly packaged release.
0.999999999/1.0b10
~~~~~~~~~~~~~~~~~~
Released on July 15, 2016
* Fix attribute order going to the tree builder to be document order
instead of reverse document order(!).
0.99999999/1.0b9
~~~~~~~~~~~~~~~~
Released on July 14, 2016
* **Added ordereddict as a mandatory dependency on Python 2.6.**
* Added ``lxml``, ``genshi``, ``datrie``, ``charade``, and ``all``
extras that will do the right thing based on the specific
interpreter implementation.
* Now requires the ``mock`` package for the testsuite.
* Cease supporting DATrie under PyPy.
* **Remove PullDOM support, as this hasn't ever been properly
tested, doesn't entirely work, and as far as I can tell is
completely unused by anyone.**
* Move testsuite to ``py.test``.
* **Fix #124: move to webencodings for decoding the input byte stream;
this makes html5lib compliant with the Encoding Standard, and
introduces a required dependency on webencodings.**
* **Cease supporting Python 3.2 (in both CPython and PyPy forms).**
* **Fix comments containing double-dash with lxml 3.5 and above.**
* **Use scripting disabled by default (as we don't implement
scripting).**
* **Fix #11, avoiding the XSS bug potentially caused by serializer
allowing attribute values to be escaped out of in old browser versions,
changing the quote_attr_values option on serializer to take one of
three values, "always" (the old True value), "legacy" (the new option,
and the new default), and "spec" (the old False value, and the old
default).**
* **Fix #72 by rewriting the sanitizer to apply only to treewalkers
(instead of the tokenizer); as such, this will require amending all
callers of it to use it via the treewalker API.**
* **Drop support of charade, now that chardet is supported once more.**
* **Replace the charset keyword argument on parse and related methods
with a set of keyword arguments: override_encoding, transport_encoding,
same_origin_parent_encoding, likely_encoding, and default_encoding.**
* **Move filters._base, treebuilder._base, and treewalkers._base to .base
to clarify their status as public.**
* **Get rid of the sanitizer package. Merge sanitizer.sanitize into the
sanitizer.htmlsanitizer module and move that to sanitizer. This means
anyone who used sanitizer.sanitize or sanitizer.HTMLSanitizer needs no
code changes.**
* **Rename treewalkers.lxmletree to .etree_lxml and
treewalkers.genshistream to .genshi to have a consistent API.**
* Move a whole load of stuff (inputstream, ihatexml, trie, tokenizer,
utils) to be underscore prefixed to clarify their status as private.
0.9999999/1.0b8
~~~~~~~~~~~~~~~
Released on September 10, 2015
* Fix #195: fix the sanitizer to drop broken URLs (it threw an
exception between 0.9999 and 0.999999).
0.999999/1.0b7
~~~~~~~~~~~~~~
Released on July 7, 2015
* Fix #189: fix the sanitizer to allow relative URLs again (as it did
prior to 0.9999/1.0b5).
0.99999/1.0b6
~~~~~~~~~~~~~
Released on April 30, 2015
* Fix #188: fix the sanitizer to not throw an exception when sanitizing
bogus data URLs.
0.9999/1.0b5
~~~~~~~~~~~~
Released on April 29, 2015
* Fix #153: Sanitizer fails to treat some attributes as URLs. Despite how
this sounds, this has no known security implications. No known version
of IE (5.5 to current), Firefox (3 to current), Safari (6 to current),
Chrome (1 to current), or Opera (12 to current) will run any script
provided in these attributes.
* Pass error message to the ParseError exception in strict parsing mode.
* Allow data URIs in the sanitizer, with a whitelist of content-types.
* Add support for Python implementations that don't support lone
surrogates (read: Jython). Fixes #2.
* Remove localization of error messages. This functionality was totally
unused (and untested that everything was localizable), so we may as
well follow numerous browsers in not supporting translating technical
strings.
* Expose treewalkers.pprint as a public API.
* Add a documentEncoding property to HTML5Parser, fix #121.
0.999
~~~~~
Released on December 23, 2013
* Fix #127: add work-around for CPython issue #20007: .read(0) on
http.client.HTTPResponse drops the rest of the content.
* Fix #115: lxml treewalker can now deal with fragments containing, at
their root level, text nodes with non-ASCII characters on Python 2.
0.99
~~~~
Released on September 10, 2013
* No library changes from 1.0b3; released as 0.99 as pip has changed
behaviour from 1.4 to avoid installing pre-release versions per
PEP 440.
1.0b3
~~~~~
Released on July 24, 2013
* Removed ``RecursiveTreeWalker`` from ``treewalkers._base``. Any
implementation using it should be moved to
``NonRecursiveTreeWalker``, as everything bundled with html5lib has
for years.
* Fix #67 so that ``BufferedStream`` to correctly returns a bytes
object, thereby fixing any case where html5lib is passed a
non-seekable RawIOBase-like object.
1.0b2
~~~~~
Released on June 27, 2013
* Removed reordering of attributes within the serializer. There is now
an ``alphabetical_attributes`` option which preserves the previous
behaviour through a new filter. This allows attribute order to be
preserved through html5lib if the tree builder preserves order.
* Removed ``dom2sax`` from DOM treebuilders. It has been replaced by
``treeadapters.sax.to_sax`` which is generic and supports any
treewalker; it also resolves all known bugs with ``dom2sax``.
* Fix treewalker assertions on hitting bytes strings on
Python 2. Previous to 1.0b1, treewalkers coped with mixed
bytes/unicode data on Python 2; this reintroduces this prior
behaviour on Python 2. Behaviour is unchanged on Python 3.
1.0b1
~~~~~
Released on May 17, 2013
* Implementation updated to implement the `HTML specification
`_ as of 5th May
2013 (`SVN `_ revision r7867).
* Python 3.2+ supported in a single codebase using the ``six`` library.
* Removed support for Python 2.5 and older.
* Removed the deprecated Beautiful Soup 3 treebuilder.
``beautifulsoup4`` can use ``html5lib`` as a parser instead. Note that
since it doesn't support namespaces, foreign content like SVG and
MathML is parsed incorrectly.
* Removed ``simpletree`` from the package. The default tree builder is
now ``etree`` (using the ``xml.etree.cElementTree`` implementation if
available, and ``xml.etree.ElementTree`` otherwise).
* Removed the ``XHTMLSerializer`` as it never actually guaranteed its
output was well-formed XML, and hence provided little of use.
* Removed default DOM treebuilder, so ``html5lib.treebuilders.dom`` is no
longer supported. ``html5lib.treebuilders.getTreeBuilder("dom")`` will
return the default DOM treebuilder, which uses ``xml.dom.minidom``.
* Optional heuristic character encoding detection now based on
``charade`` for Python 2.6 - 3.3 compatibility.
* Optional ``Genshi`` treewalker support fixed.
* Many bugfixes, including:
* #33: null in attribute value breaks XML AttValue;
* #4: nested, indirect descendant,