# coding: utf8
"""
WeasyPrint
==========
WeasyPrint converts web documents to PDF.
The public API is what is accessible from this "root" packages
without importing sub-modules.
:copyright: Copyright 2011-2014 Simon Sapin and contributors, see AUTHORS.
:license: BSD, see LICENSE for details.
"""
from __future__ import division, unicode_literals
VERSION = '0.21'
__version__ = VERSION
# Used for 'User-Agent' in HTTP and 'Creator' in PDF
VERSION_STRING = 'WeasyPrint %s (http://weasyprint.org/)' % VERSION
__all__ = ['HTML', 'CSS', 'Document', 'Page', 'default_url_fetcher',
'VERSION']
import contextlib
import html5lib
from .urls import (fetch, default_url_fetcher, path2url, ensure_url,
url_is_absolute)
from .compat import unicode
from .logger import LOGGER
# Some import are at the end of the file (after the CSS class) is defined
# to work around circular imports.
class HTML(object):
"""Represents an HTML document parsed by `lxml `_.
You can just create an instance with a positional argument:
``doc = HTML(something)``
The class will try to guess if the input is a filename, an absolute URL,
or a file-like object.
Alternatively, use **one** named argument so that no guessing is involved:
:param filename: A filename, relative to the current directory or absolute.
:param url: An absolute, fully qualified URL.
:param file_obj: a file-like: any object with a :meth:`~file.read` method.
:param string: a string of HTML source. (This argument must be named.)
:param tree: a parsed lxml tree. (This argument must be named.)
Specifying multiple inputs is an error: ``HTML(filename=foo, url=bar)``
will raise.
You can also pass optional named arguments:
:param encoding: Force the source character encoding.
:param base_url: The base used to resolve relative URLs
(eg. in ``
``). If not provided, try to use
the input filename, URL, or ``name`` attribute of file-like objects.
:param url_fetcher: a function or other callable
with the same signature as :func:`default_url_fetcher` called to
fetch external resources such as stylesheets and images.
(See :ref:`url-fetchers`.)
:param media_type: The media type to use for ``@media``.
Defaults to ``'print'``. **Note:** In some cases like
``HTML(string=foo)`` relative URLs will be invalid if ``base_url``
is not provided.
"""
def __init__(self, guess=None, filename=None, url=None, file_obj=None,
string=None, tree=None, encoding=None, base_url=None,
url_fetcher=default_url_fetcher, media_type='print'):
result = _select_source(
guess, filename, url, file_obj, string, tree, base_url,
url_fetcher)
with result as (source_type, source, base_url, protocol_encoding):
if source_type == 'tree':
result = source
else:
if not encoding:
encoding = protocol_encoding
if isinstance(source, unicode):
encoding = None
result = html5lib.parse(
source, treebuilder='lxml', encoding=encoding,
namespaceHTMLElements=False)
assert result
base_url = find_base_url(result, base_url)
if hasattr(result, 'getroot'):
result.docinfo.URL = base_url
result = result.getroot()
else:
result.getroottree().docinfo.URL = base_url
self.root_element = result
self.base_url = base_url
self.url_fetcher = url_fetcher
self.media_type = media_type
def _ua_stylesheets(self):
return [HTML5_UA_STYLESHEET]
def _get_metadata(self):
return get_html_metadata(self.root_element)
def render(self, stylesheets=None, enable_hinting=False):
"""Lay out and paginate the document, but do not (yet) export it
to PDF or another format.
This returns a :class:`~document.Document` object which provides
access to individual pages and various meta-data.
See :meth:`write_pdf` to get a PDF directly.
.. versionadded:: 0.15
:param stylesheets:
An optional list of user stylesheets. (See
:ref:`stylesheet-origins`\.) List elements are :class:`CSS`
objects, filenames, URLs, or file-like objects.
:type enable_hinting: bool
:param enable_hinting:
Whether text, borders and background should be *hinted* to fall
at device pixel boundaries. Should be enabled for pixel-based
output (like PNG) but not vector based output (like PDF).
:returns: A :class:`~document.Document` object.
"""
return Document._render(self, stylesheets, enable_hinting)
def write_pdf(self, target=None, stylesheets=None, zoom=1):
"""Render the document to a PDF file.
This is a shortcut for calling :meth:`render`, then
:meth:`Document.write_pdf() `.
:param target:
A filename, file-like object, or :obj:`None`.
:param stylesheets:
An optional list of user stylesheets. (See
:ref:`stylesheet-origins`\.) The list’s elements are
:class:`CSS` objects, filenames, URLs, or file-like objects.
:type zoom: float
:param zoom:
The zoom factor in PDF units per CSS units.
**Warning**: All CSS units (even physical, like ``cm``)
are affected.
For values other than 1, physical CSS units will thus be “wrong”.
Page size declarations are affected too, even with keyword values
like ``@page { size: A3 landscape; }``
:returns:
The PDF as byte string if :obj:`target` is not provided or
:obj:`None`, otherwise :obj:`None` (the PDF is written to
:obj:`target`.)
"""
return self.render(stylesheets).write_pdf(target, zoom)
def write_image_surface(self, stylesheets=None, resolution=96):
surface, _width, _height = (
self.render(stylesheets, enable_hinting=True)
.write_image_surface(resolution))
return surface
def write_png(self, target=None, stylesheets=None, resolution=96):
"""Paint the pages vertically to a single PNG image.
There is no decoration around pages other than those specified in CSS
with ``@page`` rules. The final image is as wide as the widest page.
Each page is below the previous one, centered horizontally.
This is a shortcut for calling :meth:`render`, then
:meth:`Document.write_png() `.
:param target:
A filename, file-like object, or :obj:`None`.
:param stylesheets:
An optional list of user stylesheets. (See
:ref:`stylesheet-origins`\.) The list’s elements are
:class:`CSS` objects, filenames, URLs, or file-like objects.
:type resolution: float
:param resolution:
The output resolution in PNG pixels per CSS inch. At 96 dpi
(the default), PNG pixels match the CSS ``px`` unit.
:returns:
The image as byte string if :obj:`target` is not provided or
:obj:`None`, otherwise :obj:`None` (the image is written to
:obj:`target`.)
"""
png_bytes, _width, _height = (
self.render(stylesheets, enable_hinting=True)
.write_png(target, resolution))
return png_bytes
class CSS(object):
"""Represents a CSS stylesheet parsed by tinycss.
An instance is created in the same way as :class:`HTML`, except that
the ``tree`` parameter is not available. All other parameters are the same.
``CSS`` objects have no public attribute or method. They are only meant to
be used in the :meth:`~HTML.write_pdf`, :meth:`~HTML.write_png` and
:meth:`~HTML.render` methods of :class:`HTML` objects.
"""
def __init__(self, guess=None, filename=None, url=None, file_obj=None,
string=None, encoding=None, base_url=None,
url_fetcher=default_url_fetcher, _check_mime_type=False,
media_type='print'):
result = _select_source(
guess, filename, url, file_obj, string, tree=None,
base_url=base_url, url_fetcher=url_fetcher,
check_css_mime_type=_check_mime_type,)
with result as (source_type, source, base_url, protocol_encoding):
if source_type == 'string' and not isinstance(source, bytes):
# unicode, no encoding
stylesheet = PARSER.parse_stylesheet(source)
else:
if source_type == 'file_obj':
source = source.read()
stylesheet = PARSER.parse_stylesheet_bytes(
source, linking_encoding=encoding,
protocol_encoding=protocol_encoding)
self.base_url = base_url
self.rules = list(preprocess_stylesheet(
media_type, base_url, stylesheet.rules, url_fetcher))
# TODO: do not keep this self.stylesheet around?
self.stylesheet = stylesheet
for error in self.stylesheet.errors:
LOGGER.warning(error)
@contextlib.contextmanager
def _select_source(guess=None, filename=None, url=None, file_obj=None,
string=None, tree=None, base_url=None,
url_fetcher=default_url_fetcher, check_css_mime_type=False):
"""
Check that only one input is not None, and return it with the
normalized ``base_url``.
"""
if base_url is not None:
base_url = ensure_url(base_url)
nones = [guess is None, filename is None, url is None,
file_obj is None, string is None, tree is None]
if nones == [False, True, True, True, True, True]:
if hasattr(guess, 'read'):
type_ = 'file_obj'
elif url_is_absolute(guess):
type_ = 'url'
else:
type_ = 'filename'
result = _select_source(
base_url=base_url, url_fetcher=url_fetcher,
check_css_mime_type=check_css_mime_type,
# Use str() to work around http://bugs.python.org/issue4978
# See https://github.com/Kozea/WeasyPrint/issues/97
**{str(type_): guess})
with result as result:
yield result
elif nones == [True, False, True, True, True, True]:
if base_url is None:
base_url = path2url(filename)
with open(filename, 'rb') as file_obj:
yield 'file_obj', file_obj, base_url, None
elif nones == [True, True, False, True, True, True]:
with fetch(url_fetcher, url) as result:
if check_css_mime_type and result['mime_type'] != 'text/css':
LOGGER.warning(
'Unsupported stylesheet type %s for %s',
result['mime_type'], result['redirected_url'])
yield 'string', '', base_url, None
else:
proto_encoding = result.get('encoding')
if base_url is None:
base_url = result.get('redirected_url', url)
if 'string' in result:
yield 'string', result['string'], base_url, proto_encoding
else:
yield (
'file_obj', result['file_obj'], base_url,
proto_encoding)
elif nones == [True, True, True, False, True, True]:
if base_url is None:
# filesystem file-like objects have a 'name' attribute.
name = getattr(file_obj, 'name', None)
# Some streams have a .name like '', not a filename.
if name and not name.startswith('<'):
base_url = ensure_url(name)
yield 'file_obj', file_obj, base_url, None
elif nones == [True, True, True, True, False, True]:
yield 'string', string, base_url, None
elif nones == [True, True, True, True, True, False]:
yield 'tree', tree, base_url, None
else:
raise TypeError('Expected exactly one source, got ' + (
', '.join(
name for i, name in enumerate(
'guess filename url file_obj string tree'.split())
if not nones[i]
) or 'nothing'
))
# Work around circular imports.
from .css import PARSER, preprocess_stylesheet
from .html import find_base_url, HTML5_UA_STYLESHEET, get_html_metadata
from .document import Document, Page