summaryrefslogtreecommitdiff
path: root/Documentation/sphinx/kfigure.py
blob: cef4ad19624c5a37c72da2d6a223ce925633e2d4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
# -*- coding: utf-8; mode: python -*-
# pylint: disable=C0103, R0903, R0912, R0915
u"""
    scalable figure and image handling
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Sphinx extension which implements scalable image handling.

    :copyright:  Copyright (C) 2016  Markus Heiser
    :license:    GPL Version 2, June 1991 see Linux/COPYING for details.

    The build for image formats depend on image's source format and output's
    destination format. This extension implement methods to simplify image
    handling from the author's POV. Directives like ``kernel-figure`` implement
    methods *to* always get the best output-format even if some tools are not
    installed. For more details take a look at ``convert_image(...)`` which is
    the core of all conversions.

    * ``.. kernel-image``: for image handling / a ``.. image::`` replacement

    * ``.. kernel-figure``: for figure handling / a ``.. figure::`` replacement

    * ``.. kernel-render``: for render markup / a concept to embed *render*
      markups (or languages). Supported markups (see ``RENDER_MARKUP_EXT``)

      - ``DOT``: render embedded Graphviz's **DOC**
      - ``SVG``: render embedded Scalable Vector Graphics (**SVG**)
      - ... *developable*

    Used tools:

    * ``dot(1)``: Graphviz (http://www.graphviz.org). If Graphviz is not
      available, the DOT language is inserted as literal-block.

    * SVG to PDF: To generate PDF, you need at least one of this tools:

      - ``convert(1)``: ImageMagick (https://www.imagemagick.org)

    List of customizations:

    * generate PDF from SVG / used by PDF (LaTeX) builder

    * generate SVG (html-builder) and PDF (latex-builder) from DOT files.
      DOT: see http://www.graphviz.org/content/dot-language

    """

import os
from os import path
import subprocess
from hashlib import sha1
import sys

from docutils import nodes
from docutils.statemachine import ViewList
from docutils.parsers.rst import directives
from docutils.parsers.rst.directives import images
import sphinx

from sphinx.util.nodes import clean_astext
from six import iteritems

PY3 = sys.version_info[0] == 3

if PY3:
    _unicode = str
else:
    _unicode = unicode

# Get Sphinx version
major, minor, patch = sphinx.version_info[:3]
if major == 1 and minor > 3:
    # patches.Figure only landed in Sphinx 1.4
    from sphinx.directives.patches import Figure  # pylint: disable=C0413
else:
    Figure = images.Figure

__version__  = '1.0.0'

# simple helper
# -------------

def which(cmd):
    """Searches the ``cmd`` in the ``PATH`` enviroment.

    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

def mkdir(folder, mode=0o775):
    if not path.isdir(folder):
        os.makedirs(folder, mode)

def file2literal(fname):
    with open(fname, "r") as src:
        data = src.read()
        node = nodes.literal_block(data, data)
    return node

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)

def pass_handle(self, node):           # pylint: disable=W0613
    pass

# setup conversion tools and sphinx extension
# -------------------------------------------

# Graphviz's dot(1) support
dot_cmd = None

# ImageMagick' convert(1) support
convert_cmd = None


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
    )


def setupTools(app):
    u"""
    Check available build tools and log some *verbose* messages.

    This function is called once, when the builder is initiated.
    """
    global dot_cmd, convert_cmd   # pylint: disable=W0603
    app.verbose("kfigure: check installed tools ...")

    dot_cmd = which('dot')
    convert_cmd = which('convert')

    if dot_cmd:
        app.verbose("use dot(1) from: " + dot_cmd)
    else:
        app.warn("dot(1) not found, for better output quality install "
                 "graphviz from http://www.graphviz.org")
    if convert_cmd:
        app.verbose("use convert(1) from: " + convert_cmd)
    else:
        app.warn(
            "convert(1) not found, for SVG to PDF conversion install "
            "ImageMagick (https://www.imagemagick.org)")


# 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'
}

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.verbose('assert best format for: ' + img_node['uri'])

    if in_ext == '.dot':

        if not dot_cmd:
            app.verbose("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.verbose("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 = dst_fname[len(translator.builder.outdir) + 1:]

        if isNewer(dst_fname, src_fname):
            app.verbose("convert: {out}/%s already exists and is newer" % _name)

        else:
            ok = False
            mkdir(path.dirname(dst_fname))

            if in_ext == '.dot':
                app.verbose('convert DOT to: {out}/' + _name)
                ok = dot2format(app, src_fname, dst_fname)

            elif in_ext == '.svg':
                app.verbose('convert SVG to: {out}/' + _name)
                ok = svg2pdf(app, src_fname, dst_fname)

            if not ok:
                img_node.replace_self(file2literal(src_fname))


def dot2format(app, dot_fname, out_fname):
    """Converts DOT file to ``out_fname`` using ``dot(1)``.

    * ``dot_fname`` pathname of the input DOT file, including extension ``.dot``
    * ``out_fname`` pathname of the output file, including format extension

    The *format extension* depends on the ``dot`` command (see ``man dot``
    option ``-Txxx``). Normally you will use one of the following extensions:

    - ``.ps`` for PostScript,
    - ``.svg`` or ``svgz`` for Structured Vector Graphics,
    - ``.fig`` for XFIG graphics and
    - ``.png`` or ``gif`` for common bitmap graphics.

    """
    out_format = path.splitext(out_fname)[1][1:]
    cmd = [dot_cmd, '-T%s' % out_format, dot_fname]
    exit_code = 42

    with open(out_fname, "w") as out:
        exit_code = subprocess.call(cmd, stdout = out)
        if exit_code != 0:
            app.warn("Error #%d when calling: %s" % (exit_code, " ".join(cmd)))
    return bool(exit_code == 0)

def svg2pdf(app, svg_fname, pdf_fname):
    """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:
        app.warn("Error #%d when calling: %s" % (exit_code, " ".join(cmd)))
    return bool(exit_code == 0)


# image handling
# ---------------------

def visit_kernel_image(self, node):    # pylint: disable=W0613
    """Visitor of the ``kernel_image`` Node.

    Handles the ``image`` child-node with the ``convert_image(...)``.
    """
    img_node = node[0]
    convert_image(img_node, self)

class kernel_image(nodes.image):
    """Node for ``kernel-image`` directive."""
    pass

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``.
    """

    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
# ---------------------

def visit_kernel_figure(self, node):   # pylint: disable=W0613
    """Visitor of the ``kernel_figure`` Node.

    Handles the ``image`` child-node with the ``convert_image(...)``.
    """
    img_node = node[0][0]
    convert_image(img_node, self)

class kernel_figure(nodes.figure):
    """Node for ``kernel-figure`` directive."""

class KernelFigure(Figure):
    u"""KernelImage directive

    Earns everything from ``.. figure::`` directive, except *remote URI* and
    *glob* pattern.  The KernelFigure wraps a figure node into a kernel_figure
    node. See ``visit_kernel_figure``.
    """

    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 = Figure.run(self)
        if len(result) == 2 or isinstance(result[0], nodes.system_message):
            return result
        (figure_node,) = result
        # wrap figure node into a kernel_figure node / see visitors
        node = kernel_figure('', figure_node)
        return [node]


# render handling
# ---------------------

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(...)``.
    """
    app = self.builder.app
    srclang = node.get('srclang')

    app.verbose('visit kernel-render node lang: "%s"' % (srclang))

    tmp_ext = RENDER_MARKUP_EXT.get(srclang, None)
    if tmp_ext is None:
        app.warn('kernel-render: "%s" unknow / include raw.' % (srclang))
        return

    if not dot_cmd and tmp_ext == '.dot':
        app.verbose("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") 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)


class kernel_render(nodes.General, nodes.Inline, nodes.Element):
    """Node for ``kernel-render`` directive."""
    pass

class KernelRender(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 = Figure.option_spec.copy()
    option_spec['caption'] = directives.unchanged

    def run(self):
        return [self.build_node()]

    def build_node(self):

        srclang = self.arguments[0].strip()
        if srclang not in RENDER_MARKUP_EXT.keys():
            return [self.state_machine.reporter.warning(
                'Unknow 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

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