#----------------------------------------------------------------------------- # Copyright (c) 2012 - 2020, Anaconda, Inc., and Bokeh Contributors. # All rights reserved. # # The full license is in the file LICENSE.txt, distributed with this software. #----------------------------------------------------------------------------- ''' ''' #----------------------------------------------------------------------------- # Boilerplate #----------------------------------------------------------------------------- import logging # isort:skip log = logging.getLogger(__name__) #----------------------------------------------------------------------------- # Imports #----------------------------------------------------------------------------- # Standard library imports import io import os import warnings from os.path import abspath from tempfile import mkstemp from typing import TYPE_CHECKING, Any, List, Optional, Tuple, Union, cast # External imports from PIL import Image # Bokeh imports from ..document import Document from ..embed import file_html from ..models.layouts import LayoutDOM from ..resources import INLINE, Resources from .util import default_filename #----------------------------------------------------------------------------- # Globals and constants #----------------------------------------------------------------------------- __all__ = ( 'export_png', 'export_svg', 'export_svgs', 'get_layout_html', 'get_screenshot_as_png', 'get_svgs', ) if TYPE_CHECKING: from selenium.webdriver.remote.webdriver import WebDriver #----------------------------------------------------------------------------- # General API #----------------------------------------------------------------------------- [docs]def export_png(obj: Union[LayoutDOM, Document], *, filename: Optional[str] = None, width: Optional[int] = None, height: Optional[int] = None, webdriver: "Optional[WebDriver]" = None, timeout: int = 5) -> str: ''' 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. width (int) : the desired width of the exported layout obj only if it's a Plot instance. Otherwise the width kwarg is ignored. height (int) : the desired height of the exported layout obj only if it's a Plot instance. Otherwise the height kwarg is ignored. webdriver (selenium.webdriver) : a selenium webdriver instance to use to export the image. timeout (int) : the maximum amount of time (in seconds) to wait for Bokeh to initialize (default: 5) (Added in 1.1.1). Returns: filename (str) : the filename where the static file is saved. If you would like to access an Image object directly, rather than save a file to disk, use the lower-level :func:`~bokeh.io.export.get_screenshot_as_png` function. .. warning:: Responsive sizing_modes may generate layouts with unexpected size and aspect ratios. It is recommended to use the default ``fixed`` sizing mode. ''' image = get_screenshot_as_png(obj, width=width, height=height, driver=webdriver, timeout=timeout) if filename is None: filename = default_filename("png") if image.width == 0 or image.height == 0: raise ValueError("unable to save an empty image") image.save(filename) return abspath(filename) [docs]def export_svg(obj: Union[LayoutDOM, Document], *, filename: Optional[str] = None, width: Optional[int] = None, height: Optional[int] = None, webdriver: "Optional[WebDriver]" = None, timeout: int = 5) -> List[str]: ''' Export a layout as SVG file or a document as a set of SVG files. 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. width (int) : the desired width of the exported layout obj only if it's a Plot instance. Otherwise the width kwarg is ignored. height (int) : the desired height of the exported layout obj only if it's a Plot instance. Otherwise the height kwarg is ignored. webdriver (selenium.webdriver) : a selenium webdriver instance to use to export the image. timeout (int) : the maximum amount of time (in seconds) to wait for Bokeh to initialize (default: 5) 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_svg(obj, width=width, height=height, driver=webdriver, timeout=timeout) return _write_collection(svgs, filename, "svg") [docs]def export_svgs(obj: Union[LayoutDOM, Document], *, filename: Optional[str] = None, width: Optional[int] = None, height: Optional[int] = None, webdriver: "Optional[WebDriver]" = None, timeout: int = 5) -> List[str]: ''' 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. width (int) : the desired width of the exported layout obj only if it's a Plot instance. Otherwise the width kwarg is ignored. height (int) : the desired height of the exported layout obj only if it's a Plot instance. Otherwise the height kwarg is ignored. webdriver (selenium.webdriver) : a selenium webdriver instance to use to export the image. timeout (int) : the maximum amount of time (in seconds) to wait for Bokeh to initialize (default: 5) (Added in 1.1.1). 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, width=width, height=height, driver=webdriver, timeout=timeout) if len(svgs) == 0: log.warning("No SVG Plots were found.") return [] return _write_collection(svgs, filename, "svg") #----------------------------------------------------------------------------- # Dev API #----------------------------------------------------------------------------- [docs]def get_screenshot_as_png(obj: Union[LayoutDOM, Document], *, driver: "Optional[WebDriver]" = None, timeout: int = 5, resources: Resources = INLINE, width: Optional[int] = None, height: Optional[int] = None) -> Image: ''' Get a screenshot of a ``LayoutDOM`` object. Args: obj (LayoutDOM or Document) : a Layout (Row/Column), Plot or Widget object or Document to export. driver (selenium.webdriver) : a selenium webdriver instance to use to export the image. timeout (int) : the maximum amount of time to wait for initialization. It will be used as a timeout for loading Bokeh, then when waiting for the layout to be rendered. Returns: image (PIL.Image.Image) : a pillow image loaded from PNG. .. warning:: Responsive sizing_modes may generate layouts with unexpected size and aspect ratios. It is recommended to use the default ``fixed`` sizing mode. ''' from .webdriver import webdriver_control with _tmp_html() as tmp: html = get_layout_html(obj, resources=resources, width=width, height=height) with open(tmp.path, mode="w", encoding="utf-8") as file: file.write(html) web_driver = driver if driver is not None else webdriver_control.get() web_driver.maximize_window() web_driver.get("file:///" + tmp.path) wait_until_render_complete(web_driver, timeout) [width, height, dpr] = _maximize_viewport(web_driver) png = web_driver.get_screenshot_as_png() return (Image.open(io.BytesIO(png)) .convert("RGBA") .crop((0, 0, width*dpr, height*dpr)) .resize((width, height))) def get_svg(obj: Union[LayoutDOM, Document], *, driver: "Optional[WebDriver]" = None, timeout: int = 5, resources: Resources = INLINE, width: Optional[int] = None, height: Optional[int] = None) -> List[str]: from .webdriver import webdriver_control with _tmp_html() as tmp: html = get_layout_html(obj, resources=resources, width=width, height=height) with open(tmp.path, mode="w", encoding="utf-8") as file: file.write(html) web_driver = driver if driver is not None else webdriver_control.get() web_driver.get("file:///" + tmp.path) wait_until_render_complete(web_driver, timeout) svgs = cast(List[str], web_driver.execute_script(_SVG_SCRIPT)) return svgs def get_svgs(obj: Union[LayoutDOM, Document], *, driver: "Optional[WebDriver]" = None, timeout: int = 5, resources: Resources = INLINE, width: Optional[int] = None, height: Optional[int] = None) -> List[str]: from .webdriver import webdriver_control with _tmp_html() as tmp: html = get_layout_html(obj, resources=resources, width=width, height=height) with open(tmp.path, mode="w", encoding="utf-8") as file: file.write(html) web_driver = driver if driver is not None else webdriver_control.get() web_driver.get("file:///" + tmp.path) wait_until_render_complete(web_driver, timeout) svgs = cast(List[str], web_driver.execute_script(_SVGS_SCRIPT)) return svgs [docs]def get_layout_html(obj: Union[LayoutDOM, Document], *, resources: Resources = INLINE, width: Optional[int] = None, height: Optional[int] = None) -> str: ''' ''' resize = False if width is not None or height is not None: # Defer this import, it is expensive from ..models.plots import Plot if not isinstance(obj, Plot): warnings.warn("Export method called with height or width kwargs on a non-Plot layout. The size values will be ignored.") else: resize = True old_width = obj.plot_width old_height = obj.plot_height if width is not None: obj.plot_width = width if height is not None: obj.plot_height = height template = r"""\ {% block preamble %} <style> html, body { box-sizing: border-box; width: 100%; height: 100%; margin: 0; border: 0; padding: 0; overflow: hidden; } </style> {% endblock %} """ try: html = file_html(obj, resources, title="", template=template, suppress_callback_warning=True, _always_new=True) finally: if resize: assert isinstance(obj, Plot) obj.plot_width = old_width obj.plot_height = old_height return html def wait_until_render_complete(driver: "WebDriver", timeout: int) -> None: ''' ''' from selenium.webdriver.support.ui import WebDriverWait from selenium.common.exceptions import TimeoutException def is_bokeh_loaded(driver: "WebDriver") -> bool: return cast(bool, driver.execute_script(''' return typeof Bokeh !== "undefined" && Bokeh.documents != null && Bokeh.documents.length != 0 ''')) try: WebDriverWait(driver, timeout, poll_frequency=0.1).until(is_bokeh_loaded) except TimeoutException as e: _log_console(driver) raise RuntimeError('Bokeh was not loaded in time. Something may have gone wrong.') from e driver.execute_script(_WAIT_SCRIPT) def is_bokeh_render_complete(driver: "WebDriver") -> bool: return cast(bool, driver.execute_script('return window._bokeh_render_complete;')) try: WebDriverWait(driver, timeout, poll_frequency=0.1).until(is_bokeh_render_complete) except TimeoutException: log.warning("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: _log_console(driver) #----------------------------------------------------------------------------- # Private API #----------------------------------------------------------------------------- def _write_collection(items: List[str], filename: Union[str, None], ext: str) -> List[str]: if filename is None: filename = default_filename(ext) filenames = [] for i, item in enumerate(items): if i > 0: idx = filename.find(f".{ext}") filename = filename[:idx] + f"_{i}" + filename[idx:] with open(filename, mode="w", encoding="utf-8") as f: f.write(item) filenames.append(filename) return filenames def _log_console(driver: "WebDriver") -> None: levels = {'WARNING', 'ERROR', 'SEVERE'} try: logs = driver.get_log('browser') except Exception: return messages = [ log.get("message") for log in logs if log.get('level') in levels ] if len(messages) > 0: log.warning("There were browser warnings and/or errors that may have affected your export") for message in messages: log.warning(message) def _maximize_viewport(web_driver: "WebDriver") -> Tuple[int, int, int]: calculate_viewport_size = """\ const root = document.getElementsByClassName("bk-root")[0] const {width, height} = root.children[0].getBoundingClientRect() return [width, height, window.devicePixelRatio] """ viewport_size: Tuple[int, int, int] = web_driver.execute_script(calculate_viewport_size) calculate_window_size = """\ const [width, height, dpr] = arguments return [ // XXX: outer{Width,Height} can be 0 in headless mode under certain window managers Math.max(0, window.outerWidth - window.innerWidth) + width*dpr, Math.max(0, window.outerHeight - window.innerHeight) + height*dpr, ] """ [width, height] = web_driver.execute_script(calculate_window_size, *viewport_size) eps = 100 # XXX: can't set window size exactly in certain window managers, crop it to size later web_driver.set_window_size(width + eps, height + eps) return viewport_size _SVGS_SCRIPT = """ const {LayoutDOMView} = Bokeh.require("models/layouts/layout_dom") const {PlotView} = Bokeh.require("models/plots/plot") function* collect_svgs(views) { for (const view of views) { if (view instanceof LayoutDOMView) { yield* collect_svgs(view.child_views.values()) } if (view instanceof PlotView && view.model.output_backend == "svg") { const {ctx} = view.canvas_view.compose() yield ctx.get_serialized_svg(true) } } } const root_views = Object.values(Bokeh.index) return [...collect_svgs(root_views)] """ _SVG_SCRIPT = """\ function* export_svgs(views) { for (const view of views) { // TODO: use to_blob() API in future const {ctx} = view.export("svg") yield ctx.get_serialized_svg(true) } } const root_views = Object.values(Bokeh.index) return [...export_svgs(root_views)] """ _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 = Bokeh.documents[0]; if (doc.is_idle) done(); else doc.idle.connect(done); """ class _TempFile: _closed: bool = False fd: int path: str def __init__(self, *, prefix: str = "tmp", suffix: str = "") -> None: self.fd, self.path = mkstemp(prefix=prefix, suffix=suffix) def __enter__(self) -> "_TempFile": return self def __exit__(self, exc: Any, value: Any, tb: Any) -> None: self.close() def __del__(self) -> None: self.close() def close(self) -> None: if self._closed: return try: os.close(self.fd) except OSError: pass try: os.unlink(self.path) except OSError: pass self._closed = True def _tmp_html() -> _TempFile: return _TempFile(prefix="bokeh", suffix=".html") #----------------------------------------------------------------------------- # Code #-----------------------------------------------------------------------------