# -*- coding: utf-8; mode: python -*-
# SPDX-License-Identifier: AGPL-3.0-or-later
# pylint: disable=invalid-name, missing-docstring, too-many-branches
# pylint: disable=unnecessary-pass
"""\
scalable figure and image handling
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sphinx extension which implements scalable image handling.
User documentation see :ref:`kfigure`
"""
import os
import pathlib
from os import path
import subprocess
from hashlib import sha1
import logging
from docutils import nodes
from docutils.statemachine import ViewList
from docutils.parsers.rst import directives
from docutils.parsers.rst.directives import images
from sphinx.util.nodes import clean_astext
from six import iteritems
__version__ = '3.0'
app_log = logging.getLogger('application')
# simple helper
# -------------
[docs]
def which(cmd): # pylint: disable=inconsistent-return-statements
"""Searches the ``cmd`` in the ``PATH`` environment.
This *which* searches the PATH for executable ``cmd`` . First match is
returned, if nothing is found, ``None`` is returned.
"""
envpath = os.environ.get('PATH', None) or os.defpath
for folder in envpath.split(os.pathsep):
fname = folder + os.sep + cmd
if path.isfile(fname):
return fname
[docs]
def mkdir(folder, mode=0o775):
if not path.isdir(folder):
os.makedirs(folder, mode)
[docs]
def file2literal(fname):
with open(fname, "r", encoding="utf-8") as src:
data = src.read()
node = nodes.literal_block(data, data)
return node
[docs]
def isNewer(path1, path2):
"""Returns True if ``path1`` is newer than ``path2``
If ``path1`` exists and is newer than ``path2`` the function returns
``True`` is returned otherwise ``False``
"""
return (path.exists(path1)
and os.stat(path1).st_ctime > os.stat(path2).st_ctime)
[docs]
def pass_handle(self, node): # pylint: disable=unused-argument
pass
# setup conversion tools and sphinx extension
# -------------------------------------------
# Graphviz's dot(1) support
dot_cmd = None
# ImageMagick' convert(1) support
convert_cmd = None
[docs]
def setup(app):
# check toolchain first
app.connect('builder-inited', setupTools)
# image handling
app.add_directive("kernel-image", KernelImage)
app.add_node(kernel_image,
html = (visit_kernel_image, pass_handle),
latex = (visit_kernel_image, pass_handle),
texinfo = (visit_kernel_image, pass_handle),
text = (visit_kernel_image, pass_handle),
man = (visit_kernel_image, pass_handle), )
# figure handling
app.add_directive("kernel-figure", KernelFigure)
app.add_node(kernel_figure,
html = (visit_kernel_figure, pass_handle),
latex = (visit_kernel_figure, pass_handle),
texinfo = (visit_kernel_figure, pass_handle),
text = (visit_kernel_figure, pass_handle),
man = (visit_kernel_figure, pass_handle), )
# render handling
app.add_directive('kernel-render', KernelRender)
app.add_node(kernel_render,
html = (visit_kernel_render, pass_handle),
latex = (visit_kernel_render, pass_handle),
texinfo = (visit_kernel_render, pass_handle),
text = (visit_kernel_render, pass_handle),
man = (visit_kernel_render, pass_handle), )
app.connect('doctree-read', add_kernel_figure_to_std_domain)
return dict(
version = __version__,
parallel_read_safe = True,
parallel_write_safe = True
)
# integrate conversion tools
# --------------------------
RENDER_MARKUP_EXT = {
# The '.ext' must be handled by convert_image(..) function's *in_ext* input.
# <name> : <.ext>
'DOT' : '.dot',
'SVG' : '.svg'
}
[docs]
def convert_image(img_node, translator, src_fname=None):
"""Convert a image node for the builder.
Different builder prefer different image formats, e.g. *latex* builder
prefer PDF while *html* builder prefer SVG format for images.
This function handles output image formats in dependence of source the
format (of the image) and the translator's output format.
"""
app = translator.builder.app
fname, in_ext = path.splitext(path.basename(img_node['uri']))
if src_fname is None:
src_fname = path.join(translator.builder.srcdir, img_node['uri'])
if not path.exists(src_fname):
src_fname = path.join(translator.builder.outdir, img_node['uri'])
dst_fname = None
# in kernel builds, use 'make SPHINXOPTS=-v' to see verbose messages
app_log.info('assert best format for: %s', img_node['uri'])
if in_ext == '.dot':
if not dot_cmd:
app_log.info("dot from graphviz not available / include DOT raw.")
img_node.replace_self(file2literal(src_fname))
elif translator.builder.format == 'latex':
dst_fname = path.join(translator.builder.outdir, fname + '.pdf')
img_node['uri'] = fname + '.pdf'
img_node['candidates'] = {'*': fname + '.pdf'}
elif translator.builder.format == 'html':
dst_fname = path.join(
translator.builder.outdir,
translator.builder.imagedir,
fname + '.svg')
img_node['uri'] = path.join(
translator.builder.imgpath, fname + '.svg')
img_node['candidates'] = {
'*': path.join(translator.builder.imgpath, fname + '.svg')}
else:
# all other builder formats will include DOT as raw
img_node.replace_self(file2literal(src_fname))
elif in_ext == '.svg':
if translator.builder.format == 'latex':
if convert_cmd is None:
app_log.info("no SVG to PDF conversion available / include SVG raw.")
img_node.replace_self(file2literal(src_fname))
else:
dst_fname = path.join(translator.builder.outdir, fname + '.pdf')
img_node['uri'] = fname + '.pdf'
img_node['candidates'] = {'*': fname + '.pdf'}
if dst_fname:
# the builder needs not to copy one more time, so pop it if exists.
translator.builder.images.pop(img_node['uri'], None)
_name = pathlib.Path(dst_fname).relative_to(translator.builder.outdir)
if isNewer(dst_fname, src_fname):
app_log.info("convert: {out}/%s already exists and is newer", _name)
else:
ok = False
mkdir(path.dirname(dst_fname))
if in_ext == '.dot':
app_log.info('convert DOT to: {out}/%s', _name)
ok = dot2format(app, src_fname, dst_fname)
elif in_ext == '.svg':
app_log.info('convert SVG to: {out}/%s', _name)
ok = svg2pdf(app, src_fname, dst_fname)
if not ok:
img_node.replace_self(file2literal(src_fname))
[docs]
def svg2pdf(app, svg_fname, pdf_fname): # pylint: disable=unused-argument
"""Converts SVG to PDF with ``convert(1)`` command.
Uses ``convert(1)`` from ImageMagick (https://www.imagemagick.org) for
conversion. Returns ``True`` on success and ``False`` if an error occurred.
* ``svg_fname`` pathname of the input SVG file with extension (``.svg``)
* ``pdf_name`` pathname of the output PDF file with extension (``.pdf``)
"""
cmd = [convert_cmd, svg_fname, pdf_fname]
# use stdout and stderr from parent
exit_code = subprocess.call(cmd)
if exit_code != 0:
# pylint: disable=deprecated-method
app_log.warn("Error #%d when calling: %s", exit_code, " ".join(cmd))
return bool(exit_code == 0)
# image handling
# ---------------------
[docs]
def visit_kernel_image(self, node):
"""Visitor of the ``kernel_image`` Node.
Handles the ``image`` child-node with the ``convert_image(...)``.
"""
img_node = node[0]
convert_image(img_node, self)
[docs]
class kernel_image(nodes.image):
"""Node for ``kernel-image`` directive."""
pass
[docs]
class KernelImage(images.Image):
u"""KernelImage directive
Earns everything from ``.. image::`` directive, except *remote URI* and
*glob* pattern. The KernelImage wraps a image node into a
kernel_image node. See ``visit_kernel_image``.
"""
[docs]
def run(self):
uri = self.arguments[0]
if uri.endswith('.*') or uri.find('://') != -1:
raise self.severe(
'Error in "%s: %s": glob pattern and remote images are not allowed'
% (self.name, uri))
result = images.Image.run(self)
if len(result) == 2 or isinstance(result[0], nodes.system_message):
return result
(image_node,) = result
# wrap image node into a kernel_image node / see visitors
node = kernel_image('', image_node)
return [node]
# figure handling
# ---------------------
# render handling
# ---------------------
[docs]
def visit_kernel_render(self, node):
"""Visitor of the ``kernel_render`` Node.
If rendering tools available, save the markup of the ``literal_block`` child
node into a file and replace the ``literal_block`` node with a new created
``image`` node, pointing to the saved markup file. Afterwards, handle the
image child-node with the ``convert_image(...)``.
"""
srclang = node.get('srclang')
app_log.info('visit kernel-render node lang: "%s"', srclang)
tmp_ext = RENDER_MARKUP_EXT.get(srclang, None)
if tmp_ext is None:
app_log.warning('kernel-render: "%s" unknown / include raw', srclang)
return
if not dot_cmd and tmp_ext == '.dot':
app_log.info("dot from graphviz not available / include raw.")
return
literal_block = node[0]
code = literal_block.astext()
hashobj = code.encode('utf-8') # str(node.attributes)
fname = path.join('%s-%s' % (srclang, sha1(hashobj).hexdigest()))
tmp_fname = path.join(
self.builder.outdir, self.builder.imagedir, fname + tmp_ext)
if not path.isfile(tmp_fname):
mkdir(path.dirname(tmp_fname))
with open(tmp_fname, "w", encoding="utf-8") as out:
out.write(code)
img_node = nodes.image(node.rawsource, **node.attributes)
img_node['uri'] = path.join(self.builder.imgpath, fname + tmp_ext)
img_node['candidates'] = {
'*': path.join(self.builder.imgpath, fname + tmp_ext)}
literal_block.replace_self(img_node)
convert_image(img_node, self, tmp_fname)
[docs]
class kernel_render(nodes.General, nodes.Inline, nodes.Element):
"""Node for ``kernel-render`` directive."""
pass
[docs]
class KernelRender(images.Figure):
u"""KernelRender directive
Render content by external tool. Has all the options known from the
*figure* directive, plus option ``caption``. If ``caption`` has a
value, a figure node with the *caption* is inserted. If not, a image node is
inserted.
The KernelRender directive wraps the text of the directive into a
literal_block node and wraps it into a kernel_render node. See
``visit_kernel_render``.
"""
has_content = True
required_arguments = 1
optional_arguments = 0
final_argument_whitespace = False
# earn options from 'figure'
option_spec = images.Figure.option_spec.copy()
option_spec['caption'] = directives.unchanged
[docs]
def run(self):
return [self.build_node()]
[docs]
def build_node(self):
srclang = self.arguments[0].strip()
if srclang not in RENDER_MARKUP_EXT.keys():
return [self.state_machine.reporter.warning(
'Unknown source language "%s", use one of: %s.' % (
srclang, ",".join(RENDER_MARKUP_EXT.keys())),
line=self.lineno)]
code = '\n'.join(self.content)
if not code.strip():
return [self.state_machine.reporter.warning(
'Ignoring "%s" directive without content.' % (
self.name),
line=self.lineno)]
node = kernel_render()
node['alt'] = self.options.get('alt','')
node['srclang'] = srclang
literal_node = nodes.literal_block(code, code)
node += literal_node
caption = self.options.get('caption')
if caption:
# parse caption's content
parsed = nodes.Element()
self.state.nested_parse(
ViewList([caption], source=''), self.content_offset, parsed)
caption_node = nodes.caption(
parsed[0].rawsource, '', *parsed[0].children)
caption_node.source = parsed[0].source
caption_node.line = parsed[0].line
figure_node = nodes.figure('', node)
for k,v in self.options.items():
figure_node[k] = v
figure_node += caption_node
node = figure_node
return node
[docs]
def add_kernel_figure_to_std_domain(app, doctree):
"""Add kernel-figure anchors to 'std' domain.
The ``StandardDomain.process_doc(..)`` method does not know how to resolve
the caption (label) of ``kernel-figure`` directive (it only knows about
standard nodes, e.g. table, figure etc.). Without any additional handling
this will result in a 'undefined label' for kernel-figures.
This handle adds labels of kernel-figure to the 'std' domain labels.
"""
std = app.env.domains["std"]
docname = app.env.docname
labels = std.data["labels"]
for name, explicit in iteritems(doctree.nametypes):
if not explicit:
continue
labelid = doctree.nameids[name]
if labelid is None:
continue
node = doctree.ids[labelid]
if node.tagname == 'kernel_figure':
for n in node.next_node():
if n.tagname == 'caption':
sectname = clean_astext(n)
# add label to std domain
labels[name] = docname, labelid, sectname
break
