Coverage for src/mkdocs_gallery/scrapers.py: 84%

1# Authors: Sylvain MARIE <sylvain.marie@se.com>

2# + All contributors to <https://github.com/smarie/mkdocs-gallery>

4# Original idea and code: sphinx-gallery, <https://sphinx-gallery.github.io>

5# License: 3-clause BSD, <https://github.com/smarie/mkdocs-gallery/blob/master/LICENSE>

6"""

7Scrapers for embedding images

8=============================

10Collect images that have been produced by code blocks.

12The only scrapers we support are Matplotlib and Mayavi, others should

13live in modules that will support them (e.g., PyVista, Plotly). Scraped

14images are injected as rst ``image-sg`` directives into the ``.md``

15file generated for each example script.

16"""

18import os

19import re

20import sys

21from packaging.version import parse as parse_version

22from pathlib import Path

23from textwrap import indent

24from typing import Dict, List, Optional

25from warnings import filterwarnings, warn

27from .errors import ExtensionError

28from .gen_data_model import GalleryScript

29from .utils import optipng, rescale_image

31__all__ = [

32 "save_figures",

33 "figure_md_or_html",

34 "clean_modules",

35 "matplotlib_scraper",

36 "mayavi_scraper",

37 "pyvista_scraper",

38]

41###############################################################################

42# Scrapers

45def _import_matplotlib():

46 """Import matplotlib safely."""

47 # make sure that the Agg backend is set before importing any

48 # matplotlib

49 import matplotlib

51 matplotlib.use("agg")

52 matplotlib_backend = matplotlib.get_backend().lower()

54 filterwarnings(

55 "ignore",

56 category=UserWarning,

57 message="Matplotlib is currently using agg, which is a" " non-GUI backend, so cannot show the figure.",

58 )

60 if matplotlib_backend != "agg": 60 ↛ 61line 60 didn't jump to line 61, because the condition on line 60 was never true

61 raise ExtensionError(

62 "mkdocs-gallery relies on the matplotlib 'agg' backend to "

63 "render figures and write them to files. You are "

64 "currently using the {} backend. mkdocs-gallery will "

65 "terminate the build now, because changing backends is "

66 "not well supported by matplotlib. We advise you to move "

67 "mkdocs_gallery imports before any matplotlib-dependent "

68 "import. Moving mkdocs_gallery imports at the top of "

69 "your conf.py file should fix this issue".format(matplotlib_backend)

70 )

72 import matplotlib.pyplot as plt

74 return matplotlib, plt

77def _matplotlib_fig_titles(fig):

78 titles = []

79 # get supertitle if exists

80 suptitle = getattr(fig, "_suptitle", None)

81 if suptitle is not None: 81 ↛ 82line 81 didn't jump to line 82, because the condition on line 81 was never true

82 titles.append(suptitle.get_text())

83 # get titles from all axes, for all locs

84 title_locs = ["left", "center", "right"]

85 for ax in fig.axes:

86 for loc in title_locs:

87 text = ax.get_title(loc=loc)

88 if text:

89 titles.append(text)

90 fig_titles = ", ".join(titles)

91 return fig_titles

94_ANIMATION_RST = """

95<div class="mkd-glr-animation">

96{html}

97</div>

98"""

100

101def matplotlib_scraper(block, script: GalleryScript, **kwargs):

102 """Scrape Matplotlib images.

103

104 Parameters

105 ----------

106 block : tuple

107 A tuple containing the (label, content, line_number) of the block.

108

109 script : GalleryScript

110 Dict of block variables.

111

112 **kwargs : dict

113 Additional keyword arguments to pass to

114 :meth:`~matplotlib.figure.Figure.savefig`, e.g. ``format='svg'``.

115 The ``format`` kwarg in particular is used to set the file extension

116 of the output file (currently only 'png', 'jpg', and 'svg' are

117 supported).

118

119 Returns

120 -------

121 md : str

122 The Markdown that will be rendered to HTML containing

123 the images. This is often produced by :func:`figure_md_or_html`.

124 """

125 try:

126 matplotlib, plt = _import_matplotlib()

127 except ImportError:

128 # Matplotlib is not installed. Ignore

129 # Note: we should better remove this (and the same in _reset_matplotlib)

130 # and auto-adjust the corresponding config option defaults (image_scrapers, reset_modules) when

131 # matplotlib is not present

132 return ""

133

134 gallery_conf = script.gallery_conf

135 from matplotlib.animation import Animation

136

137 image_mds = []

138

139 # Check for srcset hidpi images

140 srcset = gallery_conf.get("image_srcset", [])

141 srcset_mult_facs = [1] # one is always supplied...

142 for st in srcset:

143 if (len(st) > 0) and (st[-1] == "x"): 143 ↛ 146line 143 didn't jump to line 146, because the condition on line 143 was never false

144 # "2x" = "2.0"

145 srcset_mult_facs += [float(st[:-1])]

146 elif st == "":

147 pass

148 else:

149 raise ExtensionError(

150 f'Invalid value for image_srcset parameter: "{st}". '

151 "Must be a list of strings with the multiplicative "

152 'factor followed by an "x". e.g. ["2.0x", "1.5x"]'

153 )

154

155 # Check for animations

156 anims = list()

157 if gallery_conf.get("matplotlib_animations", False): 157 ↛ 163line 157 didn't jump to line 163, because the condition on line 157 was never false

158 for ani in script.run_vars.example_globals.values():

159 if isinstance(ani, Animation):

160 anims.append(ani)

161

162 # Then standard images

163 for fig_num, image_path in zip(plt.get_fignums(), script.run_vars.image_path_iterator):

164 image_path = Path(image_path)

165 if "format" in kwargs: 165 ↛ 166line 165 didn't jump to line 166, because the condition on line 165 was never true

166 image_path = image_path.with_suffix("." + kwargs["format"])

167

168 # Set the fig_num figure as the current figure as we can't save a figure that's not the current figure.

169 fig = plt.figure(fig_num)

170

171 # Deal with animations

172 cont = False

173 for anim in anims:

174 if anim._fig is fig: 174 ↛ 173line 174 didn't jump to line 173, because the condition on line 174 was never false

175 image_mds.append(_anim_md(anim, str(image_path), gallery_conf))

176 cont = True

177 break

178 if cont:

179 continue

180

181 # get fig titles

182 fig_titles = _matplotlib_fig_titles(fig)

183 to_rgba = matplotlib.colors.colorConverter.to_rgba

184

185 # shallow copy should be fine here, just want to avoid changing

186 # "kwargs" for subsequent figures processed by the loop

187 these_kwargs = kwargs.copy()

188 for attr in ["facecolor", "edgecolor"]:

189 fig_attr = getattr(fig, "get_" + attr)()

190 default_attr = matplotlib.rcParams["figure." + attr]

191 if to_rgba(fig_attr) != to_rgba(default_attr) and attr not in kwargs: 191 ↛ 192line 191 didn't jump to line 192, because the condition on line 191 was never true

192 these_kwargs[attr] = fig_attr

193

194 # save the figures, and populate the srcsetpaths

195 try:

196 fig.savefig(image_path, **these_kwargs)

197 dpi0 = matplotlib.rcParams["savefig.dpi"]

198 if dpi0 == "figure": 198 ↛ 200line 198 didn't jump to line 200, because the condition on line 198 was never false

199 dpi0 = fig.dpi

200 dpi0 = these_kwargs.get("dpi", dpi0)

201 srcsetpaths = {0: image_path}

202

203 # save other srcset paths, keyed by multiplication factor:

204 for mult in srcset_mult_facs:

205 if not (mult == 1):

206 multst = f"{mult}".replace(".", "_")

207 name = f"{image_path.stem}_{multst}x{image_path.suffix}"

208 hipath = image_path.parent / Path(name)

209 hikwargs = these_kwargs.copy()

210 hikwargs["dpi"] = mult * dpi0

211 fig.savefig(hipath, **hikwargs)

212 srcsetpaths[mult] = hipath

213 srcsetpaths = [srcsetpaths]

214 except Exception:

215 plt.close("all")

216 raise

217

218 if "images" in gallery_conf["compress_images"]: 218 ↛ 219line 218 didn't jump to line 219, because the condition on line 218 was never true

219 optipng(image_path, gallery_conf["compress_images_args"])

220 for _, hipath in srcsetpaths[0].items():

221 optipng(hipath, gallery_conf["compress_images_args"])

222

223 image_mds.append((image_path, fig_titles, srcsetpaths))

224

225 plt.close("all")

226

227 # Create the markdown or html output

228 # <li>

229 # <img src="../_images/mkd_glr_plot_1_exp_001.png"

230 # srcset="../_images/mkd_glr_plot_1_exp_001.png, ../_images/mkd_glr_plot_1_exp_001_2_0x.png 2.0x"

231 # alt="Exponential function" class="sphx-glr-multi-img">

232 # </li>

233 # <li>

234 # <img src="../_images/mkd_glr_plot_1_exp_002.png"

235 # srcset="../_images/mkd_glr_plot_1_exp_002.png, ../_images/mkd_glr_plot_1_exp_002_2_0x.png 2.0x"

236 # alt="Negative exponential function" class="sphx-glr-multi-img">

237 # </li>

238

239 md = ""

240 if len(image_mds) == 1:

241 if isinstance(image_mds[0], str):

242 # an animation, see _anim_md

243 md = image_mds[0]

244 else:

245 # an image

246 image_path, fig_titles, srcsetpaths = image_mds[0]

247 md = figure_md_or_html([image_path], script, fig_titles, srcsetpaths=srcsetpaths)

248 elif len(image_mds) > 1:

249 # Old

250 # Replace the 'single' CSS class by the 'multi' one

251 # image_mds = [re.sub(r"mkd-glr-single-img", "mkd-glr-multi-img", image) for image in image_mds]

252 # image_mds = [HLIST_IMAGE_MATPLOTLIB % image for image in image_mds]

253 # md = HLIST_HEADER % (''.join(image_mds))

254

255 # New: directly use the html

256 image_htmls = []

257 for image_path, fig_titles, srcsetpaths in image_mds:

258 img_html = figure_md_or_html([image_path], script, fig_titles, srcsetpaths=srcsetpaths, raw_html=True)

259 image_htmls.append(img_html)

260 md = HLIST_HEADER % ("".join(image_htmls))

261 return md

262

263

264def _anim_md(anim, image_path, gallery_conf):

265 import matplotlib

266 from matplotlib.animation import FFMpegWriter, ImageMagickWriter

267

268 # output the thumbnail as the image, as it will just be copied

269 # if it's the file thumbnail

270 fig = anim._fig

271 image_path = image_path.replace(".png", ".gif")

272 fig_size = fig.get_size_inches()

273 thumb_size = gallery_conf["thumbnail_size"]

274 use_dpi = round(min(t_s / f_s for t_s, f_s in zip(thumb_size, fig_size)))

275 # FFmpeg is buggy for GIFs before Matplotlib 3.3.1

276 if parse_version(matplotlib.__version__) >= parse_version("3.3.1") and FFMpegWriter.isAvailable(): 276 ↛ 277line 276 didn't jump to line 277, because the condition on line 276 was never true

277 writer = "ffmpeg"

278 elif ImageMagickWriter.isAvailable(): 278 ↛ 281line 278 didn't jump to line 281, because the condition on line 278 was never false

279 writer = "imagemagick"

280 else:

281 writer = None

282 anim.save(image_path, writer=writer, dpi=use_dpi)

283 html = anim._repr_html_()

284 if html is None: # plt.rcParams['animation.html'] == 'none' 284 ↛ 286line 284 didn't jump to line 286, because the condition on line 284 was never false

285 html = anim.to_jshtml()

286 html = indent(html, " ")

287 return _ANIMATION_RST.format(html=html)

288

289

290def mayavi_scraper(block, script: GalleryScript):

291 """Scrape Mayavi images.

292

293 Parameters

294 ----------

295 block : tuple

296 A tuple containing the (label, content, line_number) of the block.

297

298 script : GalleryScript

299 Script being run

300

301 Returns

302 -------

303 md : str

304 The ReSTructuredText that will be rendered to HTML containing

305 the images. This is often produced by :func:`figure_md_or_html`.

306 """

307 try:

308 from mayavi import mlab

309 except ModuleNotFoundError:

310 warn("No module named 'mayavi', skipping mayavi image scraper.")

311 return "" # skip scraper function

312

313 image_path_iterator = script.run_vars.image_path_iterator

314 image_paths = list()

315 e = mlab.get_engine()

316 for scene, image_path in zip(e.scenes, image_path_iterator):

317 try:

318 mlab.savefig(str(image_path), figure=scene)

319 except Exception:

320 mlab.close(all=True)

321 raise

322 # make sure the image is not too large

323 rescale_image(image_path, image_path, 850, 999)

324 if "images" in script.gallery_conf["compress_images"]: 324 ↛ 325line 324 didn't jump to line 325, because the condition on line 324 was never true

325 optipng(image_path, script.gallery_conf["compress_images_args"])

326 image_paths.append(image_path)

327 mlab.close(all=True)

328 return figure_md_or_html(image_paths, script)

329

330def pyvista_scraper(block, script: GalleryScript):

331 """Scrape PyVista images.

332

333 Parameters

334 ----------

335 block : tuple

336 A tuple containing the (label, content, line_number) of the block.

337

338 script : GalleryScript

339 Script being run

340

341 Returns

342 -------

343 md : str

344 The ReSTructuredText that will be rendered to HTML containing

345 the images. This is often produced by :func:`figure_md_or_html`.

346 """

347 import pyvista as pv

348 import pyvista.plotting as pv_plt

349 import shutil

350

351 if not pv.BUILDING_GALLERY: 351 ↛ 352line 351 didn't jump to line 352, because the condition on line 351 was never true

352 raise RuntimeError(pv.BUILDING_GALLERY_ERROR_MSG)

353 if not pv.OFF_SCREEN: 353 ↛ 354line 353 didn't jump to line 354, because the condition on line 353 was never true

354 raise RuntimeError("set pyvista.OFF_SCREEN=True to use the pyvista image scraper.")

355

356 image_path_iterator = script.run_vars.image_path_iterator

357 image_paths = list()

358 try:

359 # pyvista >= 0.40

360 figures = pv_plt.plotter._ALL_PLOTTERS

361 except AttributeError:

362 # pyvista < 0.40

363 figures = pv_plt._ALL_PLOTTERS

364 for _, plotter in figures.items():

365 fname = next(image_path_iterator)

366 if hasattr(plotter, "_gif_filename"):

367 # move gif to fname

368 fname = fname.with_suffix('').with_suffix(".gif")

369 shutil.move(plotter._gif_filename, fname)

370 else:

371 plotter.screenshot(fname)

372 image_paths.append(fname)

373 pv.close_all() # close and clear all plotters

374 return figure_md_or_html(image_paths, script)

375

376

377_scraper_dict = dict(

378 matplotlib=matplotlib_scraper,

379 mayavi=mayavi_scraper,

380 pyvista=pyvista_scraper,

381)

382

383

384# For now, these are what we support

385_KNOWN_IMG_EXTS = (".png", ".svg", ".jpg", ".gif")

386

387

388class ImageNotFoundError(FileNotFoundError):

389 def __init__(self, path):

390 self.path = path

391

392 def __str__(self):

393 return f"Image {self.path} can not be found on disk, with any of the known extensions {_KNOWN_IMG_EXTS}"

394

395

396def _find_image_ext(path: Path, raise_if_not_found: bool = True) -> Path:

397 """Find an image, tolerant of different file extensions."""

398

399 for ext in _KNOWN_IMG_EXTS:

400 this_path = path.with_suffix(ext)

401 if this_path.exists():

402 break

403 else:

404 if raise_if_not_found: 404 ↛ 408line 404 didn't jump to line 408, because the condition on line 404 was never false

405 raise ImageNotFoundError(path)

406

407 # None exists. Default to png.

408 ext = ".png"

409 this_path = path.with_suffix(ext)

410

411 return this_path, ext

412

413

414def save_figures(block, script: GalleryScript):

415 """Save all open figures of the example code-block.

416

417 Parameters

418 ----------

419 block : tuple

420 A tuple containing the (label, content, line_number) of the block.

421

422 script : GalleryScript

423 Script run.

424

425 Returns

426 -------

427 images_md : str

428 md code to embed the images in the document.

429 """

430 image_path_iterator = script.run_vars.image_path_iterator

431 all_md = ""

432 prev_count = len(image_path_iterator)

433 for scraper in script.gallery_conf["image_scrapers"]:

434 # Use the scraper to generate the md containing image(s) (may be several)

435 md = scraper(block, script)

436 if not isinstance(md, str): 436 ↛ 437line 436 didn't jump to line 437, because the condition on line 436 was never true

437 raise ExtensionError(f"md from scraper {scraper!r} was not a string, got type {type(md)}:\n{md!r}")

438

439 # Make sure that all images generated by the scraper exist.

440 n_new = len(image_path_iterator) - prev_count

441 for ii in range(n_new):

442 current_path, ext = _find_image_ext(image_path_iterator.paths[prev_count + ii])

443 if not current_path.exists(): 443 ↛ 444line 443 didn't jump to line 444, because the condition on line 443 was never true

444 raise ExtensionError(f"Scraper {scraper!r} did not produce expected image:\n{current_path}")

446 all_md += md

448 return all_md

451PREFIX_LEN = len("mkd_glr_")

452

453

454def figure_md_or_html(

455 figure_paths: List[Path],

456 script: GalleryScript,

457 fig_titles: str = "",

458 srcsetpaths: List[Dict[float, Path]] = None,

459 raw_html=False,

460):

461 """Generate md or raw html for a list of image filenames.

462

463 Depending on whether we have one or more figures, we use a

464 single md call to 'image' or a horizontal list.

465

466 Parameters

467 ----------

468 figure_paths : List[Path]

469 List of strings of the figures' absolute paths.

470 sources_dir : Path

471 absolute path of Sphinx documentation sources

472 fig_titles : str

473 Titles of figures, empty string if no titles found. Currently

474 only supported for matplotlib figures, default = ''.

475 srcsetpaths : list or None

476 List of dictionaries containing absolute paths. If

477 empty, then srcset field is populated with the figure path.

478 (see ``image_srcset`` configuration option). Otherwise,

479 each dict is of the form

480 {0: /images/image.png, 2.0: /images/image_2_0x.png}

481 where the key is the multiplication factor and the contents

482 the path to the image created above.

483

484 Returns

485 -------

486 images_md : str

487 md code to embed the images in the document

488

489 The md code will have a custom ``image-sg`` directive that allows

490 multiple resolution images to be served e.g.:

491 ``:srcset: /plot_types/imgs/img_001.png,

492 /plot_types/imgs/img_2_0x.png 2.0x``

493

494 """

495

496 if srcsetpaths is None:

497 # this should never happen, but figure_md_or_html is public, so

498 # this has to be a kwarg...

499 srcsetpaths = [{0: fl} for fl in figure_paths]

500

501 # Get all images relative to the website sources root

502 sources_dir = script.gallery.all_info.mkdocs_docs_dir

503 script_md_dir = script.gallery.generated_dir

504

505 # Get alt text

506 alt = ""

507 if fig_titles:

508 alt = fig_titles

509 elif figure_paths:

510 file_name = os.path.split(str(figure_paths[0]))[1]

511 # remove ext & 'mkd_glr_' from start & n#'s from end

512 file_name_noext = os.path.splitext(file_name)[0][PREFIX_LEN:-4]

513 # replace - & _ with \s

514 file_name_final = re.sub(r"[-,_]", " ", file_name_noext)

515 alt = file_name_final

516

517 alt = _single_line_sanitize(alt)

518

519 images_md = ""

520 if len(figure_paths) == 1:

521 figure_path = figure_paths[0]

522 hinames = srcsetpaths[0]

523 srcset = _get_srcset_st(script_md_dir, hinames)

524 figure_path_rel_to_script_md_dir = figure_path.relative_to(script_md_dir).as_posix().lstrip("/")

525 if raw_html:

526 # html version

527 images_md = (

528 f'<img alt="{alt}" src="../{figure_path_rel_to_script_md_dir}" srcset="{srcset}", '

529 f'class="sphx-glr-single-img" />'

530 )

531 else:

532 # markdown version

533 images_md = f'![{alt}](./{figure_path_rel_to_script_md_dir}){{: .mkd-glr-single-img srcset="{srcset}"}}'

534

535 elif len(figure_paths) > 1: 535 ↛ 536line 535 didn't jump to line 536, because the condition on line 535 was never true

536 images_md = HLIST_HEADER

537 for nn, figure_path in enumerate(figure_paths):

538 hinames = srcsetpaths[nn]

539 srcset = _get_srcset_st(script_md_dir, hinames)

540 figure_path_rel_to_script_md_dir = figure_path.relative_to(script_md_dir).as_posix().lstrip("/")

541 images_md += HLIST_SG_TEMPLATE % (

542 alt,

543 figure_path_rel_to_script_md_dir,

544 srcset,

545 )

546

547 return images_md

548

549

550def _get_srcset_st(sources_dir: Path, hinames: Dict[float, Path]):

551 """

552 Create the srcset string for including on the md line.

553 ie. sources_dir might be /home/sample-proj/source,

554 hinames posix paths to

555 0: /home/sample-proj/source/plot_types/images/img1.png,

556 2.0: /home/sample-proj/source/plot_types/images/img1_2_0x.png,

557 The result will be:

558 '/plot_types/basic/images/mkd_glr_pie_001.png,

559 /plot_types/basic/images/mkd_glr_pie_001_2_0x.png 2.0x'

560 """

561 srcst = ""

562 for k in hinames.keys():

563 path = hinames[k].relative_to(sources_dir).as_posix().lstrip("/")

564 srcst += "../" + path

565 if k == 0:

566 srcst += ", "

567 else:

568 srcst += f" {k:1.1f}x, "

569 if srcst[-2:] == ", ": 569 ↛ 571line 569 didn't jump to line 571, because the condition on line 569 was never false

570 srcst = srcst[:-2]

571 srcst += ""

572

573 return srcst

574

575

576def _single_line_sanitize(s):

577 """Remove problematic newlines."""

578 # For example, when setting a :alt: for an image, it shouldn't have \n

579 # This is a function in case we end up finding other things to replace

580 return s.replace("\n", " ")

581

582

583# The following strings are used when we have several pictures: we use

584# an html div tag that our CSS uses to turn the lists into horizontal

585# lists.

586HLIST_HEADER = """

587<ul class="mkd-glr-horizontal">

588%s

589</ul>

590"""

591

592HLIST_IMAGE_MATPLOTLIB = """<li>

593%s

594</li>"""

595

596HLIST_SG_TEMPLATE = """

597 * ![%s](../%s){: .mkd-glr-multi-img srcset="%s"}

598"""

599

600

601###############################################################################

602# Module resetting

603

604

605def _reset_matplotlib(gallery_conf, file: Path):

606 """Reset matplotlib."""

607 try:

608 import matplotlib

609 except ImportError:

610 # Matplotlib is not present: do not care

611 pass

612 else:

613 # Proceed with resetting it

614 _, plt = _import_matplotlib()

615 plt.rcdefaults()

616

617

618def _reset_seaborn(gallery_conf, file: Path):

619 """Reset seaborn."""

620 # Horrible code to 'unload' seaborn, so that it resets

621 # its default when is load

622 # Python does not support unloading of modules

623 # https://bugs.python.org/issue9072

624 for module in list(sys.modules.keys()):

625 if "seaborn" in module:

626 del sys.modules[module]

627

628

629_reset_dict = {

630 "matplotlib": _reset_matplotlib,

631 "seaborn": _reset_seaborn,

632}

633

634

635def clean_modules(gallery_conf: Dict, file: Optional[Path]):

636 """Remove, unload, or reset modules after running each example.

637

638 After a script is executed it can load a variety of settings that one

639 does not want to influence in other examples in the gallery.

640

641 Parameters

642 ----------

643 gallery_conf : dict

644 The gallery configuration.

645

646 file : Path

647 The example being run. Will be None when this is called entering

648 a directory of examples to be built.

649 """

650 for reset_module in gallery_conf["reset_modules"]:

651 reset_module(gallery_conf, file)