panel.io Package


io Package

The io module contains utilities for loading JS components, embedding model state, and rendering panel objects.


embed Module

Various utilities for recording and embedding state in a rendered app.

panel.io.embed.embed_state(panel, model, doc, max_states=1000, max_opts=3, json=False, json_prefix='', save_path='./', load_path=None, progress=True)[source]

Embeds the state of the application on a State model which allows exporting a static version of an app. This works by finding all widgets with a predefined set of options and evaluating the cross product of the widget values and recording the resulting events to be replayed when exported. The state is recorded on a State model which is attached as an additional root on the Document.

Parameters
  • panel (panel.viewable.Reactive) – The Reactive component being exported

  • model (bokeh.model.Model) – The bokeh model being exported

  • doc (bokeh.document.Document) – The bokeh Document being exported

  • max_states (int (default=1000)) – The maximum number of states to export

  • max_opts (int (default=3)) – The max number of ticks sampled in a continuous widget like a slider

  • json (boolean (default=True)) – Whether to export the data to json files

  • save_path (str (default='./')) – The path to save json files to

  • load_path (str (default=None)) – The path or URL the json files will be loaded from.

  • progress (boolean (default=True)) – Whether to report progress

Converts links declared in Python into JS Links by using the declared forward and reverse JS transforms on the source and target.

Converts Param pane widget links into JS links if possible.


model Module

Utilities for manipulating bokeh models.

panel.io.model.add_to_doc(obj, doc, hold=False)[source]

Adds a model to the supplied Document removing it from any existing Documents.

panel.io.model.bokeh_repr(obj, depth=0, ignored=None)[source]

Returns a string repr for a bokeh model, useful for recreating panel objects using pure bokeh.

panel.io.model.diff(doc, binary=True, events=None)[source]

Returns a json diff required to update an existing plot with the latest plot data.

panel.io.model.patch_cds_msg(model, msg)[source]

Required for handling messages containing JSON serialized typed array from the frontend.

panel.io.model.remove_root(obj, replace=None)[source]

Removes the document from any previously displayed bokeh object


notebook Module

Various utilities for loading JS dependencies and rendering plots inside the Jupyter notebook.

panel.io.notebook.block_comm()[source]

Context manager to temporarily block comm push

panel.io.notebook.ipywidget(obj, **kwargs)[source]

Creates a root model from the Panel object and wraps it in a jupyter_bokeh ipywidget BokehModel.

Parameters
  • obj (object) – Any Panel object or object which can be rendered with Panel

  • **kwargs (dict) – Keyword arguments passed to the pn.panel utility function

Returns

Return type

Returns an ipywidget model which renders the Panel object.

panel.io.notebook.mimebundle_to_html(bundle)[source]

Converts a MIME bundle into HTML.

panel.io.notebook.push(doc, comm, binary=True)[source]

Pushes events stored on the document across the provided comm.

panel.io.notebook.render_mimebundle(model, doc, comm, manager=None)[source]

Displays bokeh output inside a notebook using the PyViz display and comms machinery.

panel.io.notebook.show_embed(panel, max_states=1000, max_opts=3, json=False, save_path='./', load_path=None, progress=True)[source]

Renders a static version of a panel in a notebook by evaluating the set of states defined by the widgets in the model. Note this will only work well for simple apps with a relatively small state space.

Parameters
  • max_states (int) – The maximum number of states to embed

  • max_opts (int) – The maximum number of states for a single widget

  • json (boolean (default=True)) – Whether to export the data to json files

  • save_path (str (default='./')) – The path to save json files to

  • load_path (str (default=None)) – The path or URL the json files will be loaded from.

  • progress (boolean (default=False)) – Whether to report progress

panel.io.notebook.show_server(panel, notebook_url, port)[source]

Displays a bokeh server inline in the notebook.

Parameters
  • panel (Viewable) – Panel Viewable object to launch a server for

  • notebook_url (str) – The URL of the running Jupyter notebook server

  • port (int (optional, default=0)) – Allows specifying a specific port

  • server_id (str) – Unique ID to identify the server with

Returns

server

Return type

bokeh.server.Server


resources Module

Patches bokeh resources to make it easy to add external JS and CSS resources via the panel.config object.

panel.io.resources.get_env()[source]

Get the correct Jinja2 Environment, also for frozen scripts.


save Module

Defines utilities to save panel objects to files as HTML or PNG.

panel.io.save.save(panel, filename, title=None, resources=None, template=None, template_variables=None, embed=False, max_states=1000, max_opts=3, embed_json=False, json_prefix='', save_path='./', load_path=None, progress=True)[source]

Saves Panel objects to file.

Parameters
  • panel (Viewable) – The Panel Viewable to save to file

  • filename (string or file-like object) – Filename to save the plot to

  • title (string) – Optional title for the plot

  • resources (bokeh resources) – One of the valid bokeh.resources (e.g. CDN or INLINE)

  • template – template file, as used by bokeh.file_html. If None will use bokeh defaults

  • template_variables – template_variables file dict, as used by bokeh.file_html

  • embed (bool) – Whether the state space should be embedded in the saved file.

  • max_states (int) – The maximum number of states to embed

  • max_opts (int) – The maximum number of states for a single widget

  • embed_json (boolean (default=True)) – Whether to export the data to json files

  • json_prefix (str (default='')) – Prefix for the randomly json directory

  • save_path (str (default='./')) – The path to save json files to

  • load_path (str (default=None)) – The path or URL the json files will be loaded from.

  • progress (boolean (default=True)) – Whether to report progress

panel.io.save.save_png(model, filename, template=None, template_variables=None)[source]

Saves a bokeh model to png

Parameters
  • model (bokeh.model.Model) – Model to save to png

  • filename (str) – Filename to save to

  • template – template file, as used by bokeh.file_html. If None will use bokeh defaults

  • template_variables – template_variables file dict, as used by bokeh.file_html


server Module

Inheritance diagram of panel.io.server

Utilities for creating bokeh Server instances.

class panel.io.server.ProxyFallbackHandler(application: tornado.web.Application, request: tornado.httputil.HTTPServerRequest, **kwargs: Any)[source]

Bases: tornado.web.RequestHandler

A RequestHandler that wraps another HTTP server callback and proxies the subpath.

add_header(name: str, value: Union[bytes, str, int, numbers.Integral, datetime.datetime]) → None

Adds the given response header and value.

Unlike set_header, add_header may be called multiple times to return multiple values for the same header.

check_etag_header() → bool

Checks the Etag header against requests’s If-None-Match.

Returns True if the request’s Etag matches and a 304 should be returned. For example:

self.set_etag_header()
if self.check_etag_header():
    self.set_status(304)
    return

This method is called automatically when the request is finished, but may be called earlier for applications that override compute_etag and want to do an early check for If-None-Match before completing the request. The Etag header should be set (perhaps with set_etag_header) before calling this method.

Verifies that the _xsrf cookie matches the _xsrf argument.

To prevent cross-site request forgery, we set an _xsrf cookie and include the same value as a non-cookie field with all POST requests. If the two do not match, we reject the form submission as a potential forgery.

The _xsrf value may be set as either a form field named _xsrf or in a custom HTTP header named X-XSRFToken or X-CSRFToken (the latter is accepted for compatibility with Django).

See http://en.wikipedia.org/wiki/Cross-site_request_forgery

Changed in version 3.2.2: Added support for cookie version 2. Both versions 1 and 2 are supported.

clear() → None

Resets all headers and content for this response.

clear_all_cookies(path: str = '/', domain: str = None) → None

Deletes all the cookies the user sent with this request.

See clear_cookie for more information on the path and domain parameters.

Similar to set_cookie, the effect of this method will not be seen until the following request.

Changed in version 3.2: Added the path and domain parameters.

Deletes the cookie with the given name.

Due to limitations of the cookie protocol, you must pass the same path and domain to clear a cookie as were used when that cookie was set (but there is no way to find out on the server side which values were used for a given cookie).

Similar to set_cookie, the effect of this method will not be seen until the following request.

clear_header(name: str) → None

Clears an outgoing header, undoing a previous set_header call.

Note that this method does not apply to multi-valued headers set by add_header.

compute_etag() → Optional[str]

Computes the etag header to be used for this request.

By default uses a hash of the content written so far.

May be overridden to provide custom etag implementations, or may return None to disable tornado’s default etag support.

property cookies

An alias for self.request.cookies <.httputil.HTTPServerRequest.cookies>.

create_signed_value(name: str, value: Union[str, bytes], version: int = None) → bytes

Signs and timestamps a string so it cannot be forged.

Normally used via set_secure_cookie, but provided as a separate method for non-cookie uses. To decode a value not stored as a cookie use the optional value argument to get_secure_cookie.

Changed in version 3.2.1: Added the version argument. Introduced cookie version 2 and made it the default.

create_template_loader(template_path: str) → tornado.template.BaseLoader

Returns a new template loader for the given path.

May be overridden by subclasses. By default returns a directory-based loader on the given path, using the autoescape and template_whitespace application settings. If a template_loader application setting is supplied, uses that instead.

property current_user

The authenticated user for this request.

This is set in one of two ways:

  • A subclass may override get_current_user(), which will be called automatically the first time self.current_user is accessed. get_current_user() will only be called once per request, and is cached for future access:

    def get_current_user(self):
        user_cookie = self.get_secure_cookie("user")
        if user_cookie:
            return json.loads(user_cookie)
        return None
    
  • It may be set as a normal variable, typically from an overridden prepare():

    @gen.coroutine
    def prepare(self):
        user_id_cookie = self.get_secure_cookie("user_id")
        if user_id_cookie:
            self.current_user = yield load_user(user_id_cookie)
    

Note that prepare() may be a coroutine while get_current_user() may not, so the latter form is necessary if loading the user requires asynchronous operations.

The user object may be any type of the application’s choosing.

data_received(chunk: bytes) → Optional[Awaitable[None]]

Implement this method to handle streamed request data.

Requires the .stream_request_body decorator.

May be a coroutine for flow control.

decode_argument(value: bytes, name: str = None) → str

Decodes an argument from the request.

The argument has been percent-decoded and is now a byte string. By default, this method decodes the argument as utf-8 and returns a unicode string, but this may be overridden in subclasses.

This method is used as a filter for both get_argument() and for values extracted from the url and passed to get()/post()/etc.

The name of the argument is provided if known, but may be None (e.g. for unnamed groups in the url regex).

detach() → tornado.iostream.IOStream

Take control of the underlying stream.

Returns the underlying .IOStream object and stops all further HTTP processing. Intended for implementing protocols like websockets that tunnel over an HTTP handshake.

This method is only supported when HTTP/1.1 is used.

New in version 5.1.

finish(chunk: Union[str, bytes, dict] = None) → Future[None]

Finishes this response, ending the HTTP request.

Passing a chunk to finish() is equivalent to passing that chunk to write() and then calling finish() with no arguments.

Returns a .Future which may optionally be awaited to track the sending of the response to the client. This .Future resolves when all the response data has been sent, and raises an error if the connection is closed before all data can be sent.

Changed in version 5.1: Now returns a .Future instead of None.

flush(include_footers: bool = False) → Future[None]

Flushes the current output buffer to the network.

The callback argument, if given, can be used for flow control: it will be run when all flushed data has been written to the socket. Note that only one flush callback can be outstanding at a time; if another flush occurs before the previous flush’s callback has been run, the previous callback will be discarded.

Changed in version 4.0: Now returns a .Future if no callback is given.

Changed in version 6.0: The callback argument was removed.

get_argument(name: str, default: Union[None, str, tornado.web._ArgDefaultMarker] = <tornado.web._ArgDefaultMarker object>, strip: bool = True) → Optional[str]

Returns the value of the argument with the given name.

If default is not provided, the argument is considered to be required, and we raise a MissingArgumentError if it is missing.

If the argument appears in the request more than once, we return the last value.

This method searches both the query and body arguments.

get_arguments(name: str, strip: bool = True) → List[str]

Returns a list of the arguments with the given name.

If the argument is not present, returns an empty list.

This method searches both the query and body arguments.

get_body_argument(name: str, default: Union[None, str, tornado.web._ArgDefaultMarker] = <tornado.web._ArgDefaultMarker object>, strip: bool = True) → Optional[str]

Returns the value of the argument with the given name from the request body.

If default is not provided, the argument is considered to be required, and we raise a MissingArgumentError if it is missing.

If the argument appears in the url more than once, we return the last value.

New in version 3.2.

get_body_arguments(name: str, strip: bool = True) → List[str]

Returns a list of the body arguments with the given name.

If the argument is not present, returns an empty list.

New in version 3.2.

get_browser_locale(default: str = 'en_US') → tornado.locale.Locale

Determines the user’s locale from Accept-Language header.

See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.4

Returns the value of the request cookie with the given name.

If the named cookie is not present, returns default.

This method only returns cookies that were present in the request. It does not see the outgoing cookies set by set_cookie in this handler.

get_current_user() → Any

Override to determine the current user from, e.g., a cookie.

This method may not be a coroutine.

get_login_url() → str

Override to customize the login URL based on the request.

By default, we use the login_url application setting.

get_query_argument(name: str, default: Union[None, str, tornado.web._ArgDefaultMarker] = <tornado.web._ArgDefaultMarker object>, strip: bool = True) → Optional[str]

Returns the value of the argument with the given name from the request query string.

If default is not provided, the argument is considered to be required, and we raise a MissingArgumentError if it is missing.

If the argument appears in the url more than once, we return the last value.

New in version 3.2.

get_query_arguments(name: str, strip: bool = True) → List[str]

Returns a list of the query arguments with the given name.

If the argument is not present, returns an empty list.

New in version 3.2.

Returns the given signed cookie if it validates, or None.

The decoded cookie value is returned as a byte string (unlike get_cookie).

Similar to get_cookie, this method only returns cookies that were present in the request. It does not see outgoing cookies set by set_secure_cookie in this handler.

Changed in version 3.2.1: Added the min_version argument. Introduced cookie version 2; both versions 1 and 2 are accepted by default.

Returns the signing key version of the secure cookie.

The version is returned as int.

get_status() → int

Returns the status code for our response.

get_template_namespace() → Dict[str, Any]

Returns a dictionary to be used as the default template namespace.

May be overridden by subclasses to add or modify values.

The results of this method will be combined with additional defaults in the tornado.template module and keyword arguments to render or render_string.

get_template_path() → Optional[str]

Override to customize template path for each handler.

By default, we use the template_path application setting. Return None to load templates relative to the calling file.

get_user_locale() → Optional[tornado.locale.Locale]

Override to determine the locale from the authenticated user.

If None is returned, we fall back to get_browser_locale().

This method should return a tornado.locale.Locale object, most likely obtained via a call like tornado.locale.get("en")

property locale

The locale for the current session.

Determined by either get_user_locale, which you can override to set the locale based on, e.g., a user preference stored in a database, or get_browser_locale, which uses the Accept-Language header.

log_exception(typ: Optional[Type[BaseException]], value: Optional[BaseException], tb: Optional[traceback]) → None

Override to customize logging of uncaught exceptions.

By default logs instances of HTTPError as warnings without stack traces (on the tornado.general logger), and all other exceptions as errors with stack traces (on the tornado.application logger).

New in version 3.1.

on_connection_close() → None

Called in async handlers if the client closed the connection.

Override this to clean up resources associated with long-lived connections. Note that this method is called only if the connection was closed during asynchronous processing; if you need to do cleanup after every request override on_finish instead.

Proxies may keep a connection open for a time (perhaps indefinitely) after the client has gone away, so this method may not be called promptly after the end user closes their connection.

on_finish() → None

Called after the end of a request.

Override this method to perform cleanup, logging, etc. This method is a counterpart to prepare. on_finish may not produce any output, as it is called after the response has been sent to the client.

prepare()[source]

Called at the beginning of a request before get/post/etc.

Override this method to perform common initialization regardless of the request method.

Asynchronous support: Use async def or decorate this method with .gen.coroutine to make it asynchronous. If this method returns an Awaitable execution will not proceed until the Awaitable is done.

New in version 3.1: Asynchronous support.

redirect(url: str, permanent: bool = False, status: int = None) → None

Sends a redirect to the given (optionally relative) URL.

If the status argument is specified, that value is used as the HTTP status code; otherwise either 301 (permanent) or 302 (temporary) is chosen based on the permanent argument. The default is 302 (temporary).

render(template_name: str, **kwargs: Any) → Future[None]

Renders the template with the given arguments as the response.

render() calls finish(), so no other output methods can be called after it.

Returns a .Future with the same semantics as the one returned by finish. Awaiting this .Future is optional.

Changed in version 5.1: Now returns a .Future instead of None.

render_embed_css(css_embed: Iterable[bytes]) → bytes

Default method used to render the final embedded css for the rendered webpage.

Override this method in a sub-classed controller to change the output.

render_embed_js(js_embed: Iterable[bytes]) → bytes

Default method used to render the final embedded js for the rendered webpage.

Override this method in a sub-classed controller to change the output.

render_linked_css(css_files: Iterable[str]) → str

Default method used to render the final css links for the rendered webpage.

Override this method in a sub-classed controller to change the output.

render_linked_js(js_files: Iterable[str]) → str

Default method used to render the final js links for the rendered webpage.

Override this method in a sub-classed controller to change the output.

render_string(template_name: str, **kwargs: Any) → bytes

Generate the given template with the given arguments.

We return the generated byte string (in utf8). To generate and write a template as a response, use render() above.

require_setting(name: str, feature: str = 'this feature') → None

Raises an exception if the given app setting is not defined.

reverse_url(name: str, *args: Any) → str

Alias for Application.reverse_url.

send_error(status_code: int = 500, **kwargs: Any) → None

Sends the given HTTP error code to the browser.

If flush() has already been called, it is not possible to send an error, so this method will simply terminate the response. If output has been written but not yet flushed, it will be discarded and replaced with the error page.

Override write_error() to customize the error page that is returned. Additional keyword arguments are passed through to write_error.

Sets an outgoing cookie name/value with the given options.

Newly-set cookies are not immediately visible via get_cookie; they are not present until the next request.

expires may be a numeric timestamp as returned by time.time, a time tuple as returned by time.gmtime, or a datetime.datetime object.

Additional keyword arguments are set on the cookies.Morsel directly. See https://docs.python.org/3/library/http.cookies.html#http.cookies.Morsel for available attributes.

set_default_headers() → None

Override this to set HTTP headers at the beginning of the request.

For example, this is the place to set a custom Server header. Note that setting such headers in the normal flow of request processing may not do what you want, since headers may be reset during error handling.

set_etag_header() → None

Sets the response’s Etag header using self.compute_etag().

Note: no header will be set if compute_etag() returns None.

This method is called automatically when the request is finished.

set_header(name: str, value: Union[bytes, str, int, numbers.Integral, datetime.datetime]) → None

Sets the given response header name and value.

All header values are converted to strings (datetime objects are formatted according to the HTTP specification for the Date header).

Signs and timestamps a cookie so it cannot be forged.

You must specify the cookie_secret setting in your Application to use this method. It should be a long, random sequence of bytes to be used as the HMAC secret for the signature.

To read a cookie set with this method, use get_secure_cookie().

Note that the expires_days parameter sets the lifetime of the cookie in the browser, but is independent of the max_age_days parameter to get_secure_cookie.

Secure cookies may contain arbitrary byte values, not just unicode strings (unlike regular cookies)

Similar to set_cookie, the effect of this method will not be seen until the following request.

Changed in version 3.2.1: Added the version argument. Introduced cookie version 2 and made it the default.

set_status(status_code: int, reason: str = None) → None

Sets the status code for our response.

Parameters
  • status_code (int) – Response status code.

  • reason (str) – Human-readable reason phrase describing the status code. If None, it will be filled in from http.client.responses or “Unknown”.

Changed in version 5.0: No longer validates that the response code is in http.client.responses.

property settings

An alias for self.application.settings <Application.settings>.

static_url(path: str, include_host: bool = None, **kwargs: Any) → str

Returns a static URL for the given relative static file path.

This method requires you set the static_path setting in your application (which specifies the root directory of your static files).

This method returns a versioned url (by default appending ?v=<signature>), which allows the static files to be cached indefinitely. This can be disabled by passing include_version=False (in the default implementation; other static file implementations are not required to support this, but they may support other options).

By default this method returns URLs relative to the current host, but if include_host is true the URL returned will be absolute. If this handler has an include_host attribute, that value will be used as the default for all static_url calls that do not pass include_host as a keyword argument.

write(chunk: Union[str, bytes, dict]) → None

Writes the given chunk to the output buffer.

To write the output to the network, use the flush() method below.

If the given chunk is a dictionary, we write it as JSON and set the Content-Type of the response to be application/json. (if you want to send JSON as a different Content-Type, call set_header after calling write()).

Note that lists are not converted to JSON because of a potential cross-site security vulnerability. All JSON output should be wrapped in a dictionary. More details at http://haacked.com/archive/2009/06/25/json-hijacking.aspx/ and https://github.com/facebook/tornado/issues/1009

write_error(status_code: int, **kwargs: Any) → None

Override to implement custom error pages.

write_error may call write, render, set_header, etc to produce output as usual.

If this error was caused by an uncaught exception (including HTTPError), an exc_info triple will be available as kwargs["exc_info"]. Note that this exception may not be the “current” exception for purposes of methods like sys.exc_info() or traceback.format_exc.

xsrf_form_html() → str

An HTML <input/> element to be included with all POST forms.

It defines the _xsrf input value, which we check on all POST requests to prevent cross-site request forgery. If you have set the xsrf_cookies application setting, you must include this HTML within all of your HTML forms.

In a template, this method should be called with {% module xsrf_form_html() %}

See check_xsrf_cookie() above for more information.

property xsrf_token

The XSRF-prevention token for the current user/session.

To prevent cross-site request forgery, we set an ‘_xsrf’ cookie and include the same ‘_xsrf’ value as an argument with all POST requests. If the two do not match, we reject the form submission as a potential forgery.

See http://en.wikipedia.org/wiki/Cross-site_request_forgery

This property is of type bytes, but it contains only ASCII characters. If a character string is required, there is no need to base64-encode it; just decode the byte string as UTF-8.

Changed in version 3.2.2: The xsrf token will now be have a random mask applied in every request, which makes it safe to include the token in pages that are compressed. See http://breachattack.com for more information on the issue fixed by this change. Old (version 1) cookies will be converted to version 2 when this method is called unless the xsrf_cookie_version Application setting is set to 1.

Changed in version 4.3: The xsrf_cookie_kwargs Application setting may be used to supply additional cookie options (which will be passed directly to set_cookie). For example, xsrf_cookie_kwargs=dict(httponly=True, secure=True) will set the secure and httponly flags on the _xsrf cookie.

class panel.io.server.StoppableThread(io_loop=None, timeout=1000, **kwargs)[source]

Bases: threading.Thread

Thread class with a stop() method.

property daemon

A boolean value indicating whether this thread is a daemon thread.

This must be set before start() is called, otherwise RuntimeError is raised. Its initial value is inherited from the creating thread; the main thread is not a daemon thread and therefore all threads created in the main thread default to daemon = False.

The entire Python program exits when only daemon threads are left.

property ident

Thread identifier of this thread or None if it has not been started.

This is a nonzero integer. See the get_ident() function. Thread identifiers may be recycled when a thread exits and another thread is created. The identifier is available even after the thread has exited.

isAlive()

Return whether the thread is alive.

This method is deprecated, use is_alive() instead.

is_alive()

Return whether the thread is alive.

This method returns True just before the run() method starts until just after the run() method terminates. The module function enumerate() returns a list of all alive threads.

join(timeout=None)

Wait until the thread terminates.

This blocks the calling thread until the thread whose join() method is called terminates – either normally or through an unhandled exception or until the optional timeout occurs.

When the timeout argument is present and not None, it should be a floating point number specifying a timeout for the operation in seconds (or fractions thereof). As join() always returns None, you must call is_alive() after join() to decide whether a timeout happened – if the thread is still alive, the join() call timed out.

When the timeout argument is not present or None, the operation will block until the thread terminates.

A thread can be join()ed many times.

join() raises a RuntimeError if an attempt is made to join the current thread as that would cause a deadlock. It is also an error to join() a thread before it has been started and attempts to do so raises the same exception.

property name

A string used for identification purposes only.

It has no semantics. Multiple threads may be given the same name. The initial name is set by the constructor.

run()[source]

Method representing the thread’s activity.

You may override this method in a subclass. The standard run() method invokes the callable object passed to the object’s constructor as the target argument, if any, with sequential and keyword arguments taken from the args and kwargs arguments, respectively.

start()

Start the thread’s activity.

It must be called at most once per thread object. It arranges for the object’s run() method to be invoked in a separate thread of control.

This method will raise a RuntimeError if called more than once on the same thread object.

panel.io.server.get_server(panel, port=0, websocket_origin=None, loop=None, show=False, start=False, title=None, verbose=False, **kwargs)[source]

Returns a Server instance with this panel attached as the root app.

Parameters
  • panel (Viewable, function or {str: Viewable}) – A Panel object, a function returning a Panel object or a dictionary mapping from the URL slug to either.

  • port (int (optional, default=0)) – Allows specifying a specific port

  • websocket_origin (str or list(str) (optional)) –

    A list of hosts that can connect to the websocket.

    This is typically required when embedding a server app in an external web site.

    If None, “localhost” is used.

  • loop (tornado.ioloop.IOLoop (optional, default=IOLoop.current())) – The tornado IOLoop to run the Server on

  • show (boolean (optional, default=False)) – Whether to open the server in a new browser tab on start

  • start (boolean(optional, default=False)) – Whether to start the Server

  • title (str (optional, default=None)) – An HTML title for the application

  • verbose (boolean (optional, default=False)) – Whether to report the address and port

  • kwargs (dict) – Additional keyword arguments to pass to Server instance

Returns

server – Bokeh Server instance running this panel

Return type

bokeh.server.server.Server

panel.io.server.serve(panels, port=0, websocket_origin=None, loop=None, show=True, start=True, title=None, verbose=True, **kwargs)[source]

Allows serving one or more panel objects on a single server. The panels argument should be either a Panel object or a function returning a Panel object or a dictionary of these two. If a dictionary is supplied the keys represent the slugs at which each app is served, e.g. serve({‘app’: panel1, ‘app2’: panel2}) will serve apps at /app and /app2 on the server.

Parameters
  • panel (Viewable, function or {str: Viewable}) – A Panel object, a function returning a Panel object or a dictionary mapping from the URL slug to either.

  • port (int (optional, default=0)) – Allows specifying a specific port

  • websocket_origin (str or list(str) (optional)) –

    A list of hosts that can connect to the websocket.

    This is typically required when embedding a server app in an external web site.

    If None, “localhost” is used.

  • loop (tornado.ioloop.IOLoop (optional, default=IOLoop.current())) – The tornado IOLoop to run the Server on

  • show (boolean (optional, default=False)) – Whether to open the server in a new browser tab on start

  • start (boolean(optional, default=False)) – Whether to start the Server

  • title (str (optional, default=None)) – An HTML title for the application

  • verbose (boolean (optional, default=True)) – Whether to print the address and port

  • kwargs (dict) – Additional keyword arguments to pass to Server instance

panel.io.server.unlocked()[source]

Context manager which unlocks a Document and dispatches ModelChangedEvents triggered in the context body to all sockets on current sessions.


state Module

Various utilities for recording and embedding state in a rendered app.