#----------------------------------------------------------------------------- # Copyright (c) 2012 - 2019, Anaconda, Inc., and Bokeh Contributors. # All rights reserved. # # The full license is in the file LICENSE.txt, distributed with this software. #----------------------------------------------------------------------------- ''' Provide a Bokeh Application Handler to build up documents by running the code from ``main.py`` or ``main.ipynb`` files in specified directories. The directory may also optionally contain: * A ``server_lifecyle.py`` module to provide lifecycle callbacks for the application and sessions. * A ``static`` subdirectory containing app-specific static resources to serve. * A ``theme.yaml`` file containing a Bokeh theme to automatically apply to all new documents. * A ``templates`` subdirectory containing templates for app display A full directory layout might look like: .. code-block:: none myapp | +---main.py +---server_lifecycle.py +---static +---theme.yaml +---templates +---index.html ''' #----------------------------------------------------------------------------- # Boilerplate #----------------------------------------------------------------------------- from __future__ import absolute_import, division, print_function, unicode_literals import logging log = logging.getLogger(__name__) #----------------------------------------------------------------------------- # Imports #----------------------------------------------------------------------------- # Standard library imports from os.path import basename, dirname, exists, join # External imports from jinja2 import Environment, FileSystemLoader # Bokeh imports from .handler import Handler from .notebook import NotebookHandler from .script import ScriptHandler from .server_lifecycle import ServerLifecycleHandler #----------------------------------------------------------------------------- # Globals and constants #----------------------------------------------------------------------------- __all__ = ( 'DirectoryHandler', ) #----------------------------------------------------------------------------- # General API #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Dev API #----------------------------------------------------------------------------- [docs]class DirectoryHandler(Handler): ''' Load an application directory which modifies a Document. ''' [docs] def __init__(self, *args, **kwargs): ''' Keywords: filename (str) : a path to an application directory with either "main.py" or "main.ipynb" argv (list[str], optional) : a list of string arguments to make available as sys.argv to main.py ''' super(DirectoryHandler, self).__init__(*args, **kwargs) if 'filename' not in kwargs: raise ValueError('Must pass a filename to DirectoryHandler') src_path = kwargs['filename'] argv = kwargs.get('argv', []) main_py = join(src_path, 'main.py') main_ipy = join(src_path, 'main.ipynb') if exists(main_py) and exists(main_ipy): log.warning("Found both 'main.py' and 'main.ipynb' in %s, using 'main.py'" % (src_path)) main = main_py elif exists(main_py): main = main_py elif exists(main_ipy): main = main_ipy else: raise ValueError("No 'main.py' or 'main.ipynb' in %s" % (src_path)) self._path = src_path self._main = main handler = NotebookHandler if main.endswith('.ipynb') else ScriptHandler self._main_handler = handler(filename=self._main, argv=argv) lifecycle = join(src_path, 'server_lifecycle.py') if exists(lifecycle): self._lifecycle = lifecycle self._lifecycle_handler = ServerLifecycleHandler(filename=self._lifecycle, argv=argv) else: self._lifecycle = None self._lifecycle_handler = Handler() # no-op handler self._theme = None themeyaml = join(src_path, 'theme.yaml') if exists(themeyaml): from bokeh.themes import Theme self._theme = Theme(filename=themeyaml) appstatic = join(src_path, 'static') if exists(appstatic): self._static = appstatic self._template = None appindex = join(src_path, 'templates', 'index.html') if exists(appindex): env = Environment(loader=FileSystemLoader(dirname(appindex))) self._template = env.get_template('index.html') # Properties -------------------------------------------------------------- @property def error(self): ''' If the handler fails, may contain a related error message. ''' return self._main_handler.error or self._lifecycle_handler.error @property def error_detail(self): ''' If the handler fails, may contain a traceback or other details. ''' return self._main_handler.error_detail or self._lifecycle_handler.error_detail @property def failed(self): ''' ``True`` if the handler failed to modify the doc ''' return self._main_handler.failed or self._lifecycle_handler.failed @property def safe_to_fork(self): ''' Whether it is still safe for the Bokeh server to fork new workers. ``False`` if the configured code (script, notebook, etc.) has already been run. ''' return self._main_handler.safe_to_fork # Public methods ---------------------------------------------------------- [docs] def modify_document(self, doc): ''' Execute the configured ``main.py`` or ``main.ipynb`` to modify the document. This method will also search the app directory for any theme or template files, and automatically configure the document with them if they are found. ''' if self._lifecycle_handler.failed: return # Note: we do NOT copy self._theme, which assumes the Theme # class is immutable (has no setters) if self._theme is not None: doc.theme = self._theme if self._template is not None: doc.template = self._template # This internal handler should never add a template self._main_handler.modify_document(doc) [docs] def on_server_loaded(self, server_context): ''' Execute `on_server_unloaded`` from ``server_lifecycle.py`` (if it is defined) when the server is first started. Args: server_context (ServerContext) : ''' return self._lifecycle_handler.on_server_loaded(server_context) [docs] def on_server_unloaded(self, server_context): ''' Execute ``on_server_unloaded`` from ``server_lifecycle.py`` (if it is defined) when the server cleanly exits. (Before stopping the server's ``IOLoop``.) Args: server_context (ServerContext) : .. warning:: In practice this code may not run, since servers are often killed by a signal. ''' return self._lifecycle_handler.on_server_unloaded(server_context) [docs] def on_session_created(self, session_context): ''' Execute ``on_session_created`` from ``server_lifecycle.py`` (if it is defined) when a new session is created. Args: session_context (SessionContext) : ''' return self._lifecycle_handler.on_session_created(session_context) [docs] def on_session_destroyed(self, session_context): ''' Execute ``on_session_destroyed`` from ``server_lifecycle.py`` (if it is defined) when a session is destroyed. Args: session_context (SessionContext) : ''' return self._lifecycle_handler.on_session_destroyed(session_context) [docs] def url_path(self): ''' The last path component for the basename of the path to the configured directory. ''' if self.failed: return None else: # TODO should fix invalid URL characters return '/' + basename(self._path) #----------------------------------------------------------------------------- # Private API #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Code #-----------------------------------------------------------------------------