Source code for bokeh.io.export

#-----------------------------------------------------------------------------
# Copyright (c) 2012 - 2017, Anaconda, Inc. All rights reserved.
#
# Powered by the Bokeh Development Team.
#
# The full license is in the file LICENSE.txt, distributed with this software.
#-----------------------------------------------------------------------------
'''

'''

#-----------------------------------------------------------------------------
# Boilerplate
#-----------------------------------------------------------------------------
from __future__ import absolute_import, division, print_function, unicode_literals

import logging
log = logging.getLogger(__name__)

from bokeh.util.api import general, dev ; general, dev

#-----------------------------------------------------------------------------
# Imports
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# Standard library imports
import io
from os.path import abspath, devnull
from tempfile import NamedTemporaryFile
from warnings import warn

# External imports

# Bokeh imports
from ..resources import INLINE
from ..util.dependencies import import_required, detect_phantomjs
from .saving import save
from .util import default_filename

#-----------------------------------------------------------------------------
# Globals and constants
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#-----------------------------------------------------------------------------
# General API
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@general((1,0,0))
[docs]def export_png(obj, filename=None, height=None, width=None, webdriver=None): ''' Export the LayoutDOM object or document as a PNG. If the filename is not given, it is derived from the script name (e.g. ``/foo/myplot.py`` will create ``/foo/myplot.png``) Args: obj (LayoutDOM or Document) : a Layout (Row/Column), Plot or Widget object or Document to export. filename (str, optional) : filename to save document under (default: None) If None, infer from the filename. height (int) : the desired height of the exported layout obj only if it's a Plot instance. Otherwise the height kwarg is ignored. width (int) : the desired width of the exported layout obj only if it's a Plot instance. Otherwise the width kwarg is ignored. webdriver (selenium.webdriver) : a selenium webdriver instance to use to export the image. Returns: filename (str) : the filename where the static file is saved. .. warning:: Responsive sizing_modes may generate layouts with unexpected size and aspect ratios. It is recommended to use the default ``fixed`` sizing mode. .. warning:: Glyphs that are rendered via webgl won't be included in the generated PNG. ''' image = get_screenshot_as_png(obj, height=height, width=width, driver=webdriver) if filename is None: filename = default_filename("png") image.save(filename) return abspath(filename)
@general((1,0,0))
[docs]def export_svgs(obj, filename=None, height=None, width=None, webdriver=None): ''' Export the SVG-enabled plots within a layout. Each plot will result in a distinct SVG file. If the filename is not given, it is derived from the script name (e.g. ``/foo/myplot.py`` will create ``/foo/myplot.svg``) Args: obj (LayoutDOM object) : a Layout (Row/Column), Plot or Widget object to display filename (str, optional) : filename to save document under (default: None) If None, infer from the filename. height (int) : the desired height of the exported layout obj only if it's a Plot instance. Otherwise the height kwarg is ignored. width (int) : the desired width of the exported layout obj only if it's a Plot instance. Otherwise the width kwarg is ignored. webdriver (selenium.webdriver) : a selenium webdriver instance to use to export the image. Returns: filenames (list(str)) : the list of filenames where the SVGs files are saved. .. warning:: Responsive sizing_modes may generate layouts with unexpected size and aspect ratios. It is recommended to use the default ``fixed`` sizing mode. ''' svgs = get_svgs(obj, height=height, width=width, driver=webdriver) if len(svgs) == 0: log.warn("No SVG Plots were found.") return if filename is None: filename = default_filename("svg") filenames = [] for i, svg in enumerate(svgs): if i == 0: filename = filename else: idx = filename.find(".svg") filename = filename[:idx] + "_{}".format(i) + filename[idx:] with io.open(filename, mode="w", encoding="utf-8") as f: f.write(svg) filenames.append(filename) return filenames
#----------------------------------------------------------------------------- # Dev API #----------------------------------------------------------------------------- @dev((1,0,0))
[docs]def get_screenshot_as_png(obj, driver=None, **kwargs): ''' ''' Image = import_required('PIL.Image', 'To use bokeh.io.export_png you need pillow ' + '("conda install pillow" or "pip install pillow")') html_path = save_layout_html(obj, **kwargs) web_driver = driver if driver is not None else _create_default_webdriver() web_driver.get("file:///" + html_path) web_driver.maximize_window() ## resize for PhantomJS compat web_driver.execute_script("document.body.style.width = '100%';") wait_until_render_complete(web_driver) png = web_driver.get_screenshot_as_png() b_rect = web_driver.execute_script(_BOUNDING_RECT_SCRIPT) if driver is None: # only quit webdriver if not passed in as arg web_driver.quit() image = Image.open(io.BytesIO(png)) cropped_image = _crop_image(image, **b_rect) return cropped_image
@dev((1,0,0))
[docs]def get_svgs(obj, driver=None, **kwargs): ''' ''' html_path = save_layout_html(obj, **kwargs) web_driver = driver if driver is not None else _create_default_webdriver() web_driver.get("file:///" + html_path) wait_until_render_complete(web_driver) svgs = web_driver.execute_script(_SVG_SCRIPT) if driver is None: # only quit webdriver if not passed in as arg web_driver.quit() return svgs
@dev((1,0,0))
[docs]def save_layout_html(obj, resources=INLINE, **kwargs): ''' ''' resize = False if kwargs.get('height') is not None or kwargs.get('width') is not None: # Defer this import, it is expensive from ..models.plots import Plot if not isinstance(obj, Plot): warn("Export method called with height or width kwargs on a non-Plot layout. The size values will be ignored.") else: resize = True old_height = obj.plot_height old_width = obj.plot_width obj.plot_height = kwargs.get('height', old_height) obj.plot_width = kwargs.get('width', old_width) html_path = NamedTemporaryFile(suffix=".html").name save(obj, filename=html_path, resources=resources, title="") if resize: obj.plot_height = old_height obj.plot_width = old_width return html_path
@dev((1,0,0))
[docs]def wait_until_render_complete(driver): ''' ''' from selenium.webdriver.support.ui import WebDriverWait from selenium.common.exceptions import TimeoutException driver.execute_script(_WAIT_SCRIPT) def is_bokeh_render_complete(driver): return driver.execute_script('return window._bokeh_render_complete;') try: WebDriverWait(driver, 5, poll_frequency=0.1).until(is_bokeh_render_complete) except TimeoutException: log.warn("The webdriver raised a TimeoutException while waiting for \ a 'bokeh:idle' event to signify that the layout has rendered. \ Something may have gone wrong.") finally: browser_logs = driver.get_log('browser') severe_errors = [l for l in browser_logs if l.get('level') == 'SEVERE'] if len(severe_errors) > 0: log.warn("There were severe browser errors that may have affected your export: {}".format(severe_errors))
#----------------------------------------------------------------------------- # Private API #----------------------------------------------------------------------------- _BOUNDING_RECT_SCRIPT = """ return document.getElementsByClassName('bk-root')[0].children[0].getBoundingClientRect() """ _SVG_SCRIPT = """ var serialized_svgs = []; var svgs = document.getElementsByClassName('bk-root')[0].getElementsByTagName("svg"); for (var i = 0; i < svgs.length; i++) { var source = (new XMLSerializer()).serializeToString(svgs[i]); serialized_svgs.push(source); }; return serialized_svgs """ _WAIT_SCRIPT = """ // add private window prop to check that render is complete window._bokeh_render_complete = false; function done() { window._bokeh_render_complete = true; } var doc = window.Bokeh.documents[0]; if (doc.is_idle) done(); else doc.idle.connect(done); """ def _crop_image(image, left=0, top=0, right=0, bottom=0, **kwargs): ''' Crop the border from the layout ''' return image.crop((left, top, right, bottom)) def _create_default_webdriver(): webdriver = import_required('selenium.webdriver', 'To use bokeh.io image export functions you need selenium ' + '("conda install -c bokeh selenium" or "pip install selenium")') phantomjs_path = detect_phantomjs() return webdriver.PhantomJS(executable_path=phantomjs_path, service_log_path=devnull) #----------------------------------------------------------------------------- # Code #-----------------------------------------------------------------------------