"""
sphinx.transforms.post_transforms.images
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Docutils transforms used by Sphinx.
:copyright: Copyright 2007-2019 by the Sphinx team, see AUTHORS.
:license: BSD, see LICENSE for details.
"""
import os
from hashlib import sha1
from math import ceil
from docutils import nodes
from sphinx.locale import __
from sphinx.transforms import SphinxTransform
from sphinx.util import epoch_to_rfc1123, rfc1123_to_epoch
from sphinx.util import logging, requests
from sphinx.util.images import guess_mimetype, get_image_extension, parse_data_uri
from sphinx.util.osutil import ensuredir, movefile
if False:
# For type annotation
from typing import Any, Dict, List, Tuple # NOQA
from sphinx.application import Sphinx # NOQA
logger = logging.getLogger(__name__)
MAX_FILENAME_LEN = 32
class BaseImageConverter(SphinxTransform):
def apply(self, **kwargsj):
# type: (Any) -> None
for node in self.document.traverse(nodes.image):
if self.match(node):
self.handle(node)
def match(self, node):
# type: (nodes.image) -> bool
return True
def handle(self, node):
# type: (nodes.image) -> None
pass
@property
def imagedir(self):
# type: () -> str
return os.path.join(self.app.doctreedir, 'images')
class ImageDownloader(BaseImageConverter):
default_priority = 100
def match(self, node):
# type: (nodes.image) -> bool
if self.app.builder.supported_image_types == []:
return False
elif self.app.builder.supported_remote_images:
return False
else:
return '://' in node['uri']
def handle(self, node):
# type: (nodes.image) -> None
try:
basename = os.path.basename(node['uri'])
if '?' in basename:
basename = basename.split('?')[0]
if basename == '' or len(basename) > MAX_FILENAME_LEN:
filename, ext = os.path.splitext(node['uri'])
basename = sha1(filename.encode()).hexdigest() + ext
dirname = node['uri'].replace('://', '/').translate({ord("?"): "/",
ord("&"): "/"})
if len(dirname) > MAX_FILENAME_LEN:
dirname = sha1(dirname.encode()).hexdigest()
ensuredir(os.path.join(self.imagedir, dirname))
path = os.path.join(self.imagedir, dirname, basename)
headers = {}
if os.path.exists(path):
timestamp = ceil(os.stat(path).st_mtime) # type: float
headers['If-Modified-Since'] = epoch_to_rfc1123(timestamp)
r = requests.get(node['uri'], headers=headers)
if r.status_code >= 400:
logger.warning(__('Could not fetch remote image: %s [%d]') %
(node['uri'], r.status_code))
else:
self.app.env.original_image_uri[path] = node['uri']
if r.status_code == 200:
with open(path, 'wb') as f:
f.write(r.content)
last_modified = r.headers.get('last-modified')
if last_modified:
timestamp = rfc1123_to_epoch(last_modified)
os.utime(path, (timestamp, timestamp))
mimetype = guess_mimetype(path, default='*')
if mimetype != '*' and os.path.splitext(basename)[1] == '':
# append a suffix if URI does not contain suffix
ext = get_image_extension(mimetype)
newpath = os.path.join(self.imagedir, dirname, basename + ext)
movefile(path, newpath)
self.app.env.original_image_uri.pop(path)
self.app.env.original_image_uri[newpath] = node['uri']
path = newpath
node['candidates'].pop('?')
node['candidates'][mimetype] = path
node['uri'] = path
self.app.env.images.add_file(self.env.docname, path)
except Exception as exc:
logger.warning(__('Could not fetch remote image: %s [%s]') % (node['uri'], exc))
class DataURIExtractor(BaseImageConverter):
default_priority = 150
def match(self, node):
# type: (nodes.image) -> bool
if self.app.builder.supported_remote_images == []:
return False
elif self.app.builder.supported_data_uri_images is True:
return False
else:
return 'data:' in node['uri']
def handle(self, node):
# type: (nodes.image) -> None
image = parse_data_uri(node['uri'])
ext = get_image_extension(image.mimetype)
if ext is None:
logger.warning(__('Unknown image format: %s...'), node['uri'][:32],
location=node)
return
ensuredir(os.path.join(self.imagedir, 'embeded'))
digest = sha1(image.data).hexdigest()
path = os.path.join(self.imagedir, 'embeded', digest + ext)
self.app.env.original_image_uri[path] = node['uri']
with open(path, 'wb') as f:
f.write(image.data)
node['candidates'].pop('?')
node['candidates'][image.mimetype] = path
node['uri'] = path
self.app.env.images.add_file(self.env.docname, path)
def get_filename_for(filename, mimetype):
# type: (str, str) -> str
basename = os.path.basename(filename)
return os.path.splitext(basename)[0] + get_image_extension(mimetype)
[文档]class ImageConverter(BaseImageConverter):
"""A base class for image converters.
An image converter is kind of Docutils transform module. It is used to
convert image files which does not supported by builder to appropriate
format for that builder.
For example, :py:class:`LaTeX builder <.LaTeXBuilder>` supports PDF,
PNG and JPEG as image formats. However it does not support SVG images.
For such case, to use image converters allows to embed these
unsupported images into the document. One of image converters;
:ref:`sphinx.ext.imgconverter <sphinx.ext.imgconverter>` can convert
a SVG image to PNG format using Imagemagick internally.
There are three steps to make your custom image converter:
1. Make a subclass of ``ImageConverter`` class
2. Override ``conversion_rules``, ``is_available()`` and ``convert()``
3. Register your image converter to Sphinx using
:py:meth:`.Sphinx.add_post_transform`
"""
default_priority = 200
#: A conversion rules the image converter supports.
#: It is represented as a list of pair of source image format (mimetype) and
#: destination one::
#:
#: conversion_rules = [
#: ('image/svg+xml', 'image/png'),
#: ('image/gif', 'image/png'),
#: ('application/pdf', 'image/png'),
#: ]
conversion_rules = [] # type: List[Tuple[str, str]]
def __init__(self, *args, **kwargs):
# type: (Any, Any) -> None
self.available = None # type: bool
# the converter is available or not.
# Will be checked at first conversion
super().__init__(*args, **kwargs)
def match(self, node):
# type: (nodes.image) -> bool
if self.available is None:
self.available = self.is_available()
if not self.available:
return False
elif set(node['candidates']) & set(self.app.builder.supported_image_types):
# builder supports the image; no need to convert
return False
else:
rule = self.get_conversion_rule(node)
if rule:
return True
else:
return False
def get_conversion_rule(self, node):
# type: (nodes.image) -> Tuple[str, str]
for candidate in self.guess_mimetypes(node):
for supported in self.app.builder.supported_image_types:
rule = (candidate, supported)
if rule in self.conversion_rules:
return rule
return None
[文档] def is_available(self):
# type: () -> bool
"""Return the image converter is available or not."""
raise NotImplementedError()
def guess_mimetypes(self, node):
# type: (nodes.image) -> List[str]
if '?' in node['candidates']:
return []
elif '*' in node['candidates']:
from sphinx.util.images import guess_mimetype
return [guess_mimetype(node['uri'])]
else:
return node['candidates'].keys()
def handle(self, node):
# type: (nodes.image) -> None
_from, _to = self.get_conversion_rule(node)
if _from in node['candidates']:
srcpath = node['candidates'][_from]
else:
srcpath = node['candidates']['*']
filename = get_filename_for(srcpath, _to)
ensuredir(self.imagedir)
destpath = os.path.join(self.imagedir, filename)
abs_srcpath = os.path.join(self.app.srcdir, srcpath)
if self.convert(abs_srcpath, destpath):
if '*' in node['candidates']:
node['candidates']['*'] = destpath
else:
node['candidates'][_to] = destpath
node['uri'] = destpath
self.env.original_image_uri[destpath] = srcpath
self.env.images.add_file(self.env.docname, destpath)
[文档] def convert(self, _from, _to):
# type: (str, str) -> bool
"""Convert a image file to expected format.
*_from* is a path for source image file, and *_to* is a path for
destination file.
"""
raise NotImplementedError()
def setup(app):
# type: (Sphinx) -> Dict[str, Any]
app.add_post_transform(ImageDownloader)
app.add_post_transform(DataURIExtractor)
return {
'version': 'builtin',
'parallel_read_safe': True,
'parallel_write_safe': True,
}
