B @\@sFdZddlmZmZmZmZddlZeeZ dZ Gddde Z dS)a Provide a base class for Bokeh Application handler classes. When a Bokeh server session is initiated, the Bokeh server asks the Application for a new Document to service the session. To do this, the Application first creates a new empty Document, then it passes this new Document to the ``modify_document`` method of each of its handlers. When all handlers have updated the Document, it is used to service the user session. Below is an example outline of a custom handler that might modify documents based off information in some database: .. code-block:: python class DatabaseHandler(Handler): """ A Bokeh Application handler to initialize Documents from a database """ def modify_document(self, doc): # do some data base lookup here to generate 'plot' # add the plot to the document (i.e modify the document) doc.add_root(plot) # and return it return doc )absolute_importdivisionprint_functionunicode_literalsN)Handlerc@steZdZdZddZeddZeddZedd Zd d Z d d Z ddZ ddZ ddZ ddZddZdS)rzW Provide a mechanism for Bokeh applications to build up new Bokeh Documents. cOsd|_d|_d|_d|_dS)NF)_failed_error _error_detail_static)selfargskwargsrAlib/python3.7/site-packages/bokeh/application/handlers/handler.py__init__NszHandler.__init__cCs|jS)zE If the handler fails, may contain a related error message. )r)r rrrerrorVsz Handler.errorcCs|jS)zJ If the handler fails, may contain a traceback or other details. )r )r rrr error_detail]szHandler.error_detailcCs|jS)z; ``True`` if the handler failed to modify the doc )r)r rrrfaileddszHandler.failedcCs tddS)a Modify an application document in a specified manner. When a Bokeh server session is initiated, the Bokeh server asks the Application for a new Document to service the session. To do this, the Application first creates a new empty Document, then it passes this Document to the ``modify_document`` method of each of its handlers. When all handlers have updated the Document, it is used to service the user session. *Subclasses must implement this method* Args: doc (Document) : A Bokeh Document to update in-place Returns: Document zimplement modify_document()N)NotImplementedError)r docrrrmodify_documentmszHandler.modify_documentcCsdS)a. Execute code when the server is first started. Subclasses may implement this method to provide for any one-time initialization that is necessary after the server starts, but before any sessions are created. Args: server_context (ServerContext) : Nr)r server_contextrrron_server_loadeds zHandler.on_server_loadedcCsdS)a Execute code when the server cleanly exits. (Before stopping the server's ``IOLoop``.) Subclasses may implement this method to provide for any one-time tear down that is necessary before the server exits. Args: server_context (ServerContext) : .. warning:: In practice this code may not run, since servers are often killed by a signal. Nr)r rrrron_server_unloadedszHandler.on_server_unloadedcCsdS)a# Execute code when a new session is created. Subclasses may implement this method to provide for any per-session initialization that is necessary before ``modify_doc`` is called for the session. Args: session_context (SessionContext) : Nr)r session_contextrrron_session_createds zHandler.on_session_createdcCsdS)a Execute code when a session is destroyed. Subclasses may implement this method to provide for any per-session tear-down that is necessary when sessions are destroyed. Args: session_context (SessionContext) : Nr)r rrrron_session_destroyeds zHandler.on_session_destroyedcCs|jr dS|jSdS)zI Return a path to app-specific static resources, if applicable. N)rr )r rrr static_pathszHandler.static_pathcCsdS)aR Returns a default URL path, if applicable. Handlers subclasses may optionally implement this method, to inform the Bokeh application what URL it should be installed at. If multiple handlers specify ``url_path`` the Application will use the value from the first handler in its list of handlers. Nr)r rrrurl_paths zHandler.url_pathN)__name__ __module__ __qualname____doc__rpropertyrrrrrrrrrrrrrrrGs       r) r"Z __future__rrrrZloggingZ getLoggerrlog__all__objectrrrrr#s