bokeh.document.events¶

Provide events that represent various changes to Bokeh Documents.

These events are used internally to signal changes to Documents. For information about user-facing (e.g. UI or tool) events, see the reference for bokeh.events.

class ColumnDataChangedEvent(document, column_source, cols=None, setter=None, callback_invoker=None)[source]¶

A concrete event representing efficiently replacing all existing data for a ColumnDataSource

__init__(document, column_source, cols=None, setter=None, callback_invoker=None)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
column_source (ColumnDataSource) –
cols (list[str]) – optional explicit list of column names to update. If None, all columns will be updated (default: None)
setter (ClientSession or ServerSession or None, optional) –
This is used to prevent “boomerang” updates to Bokeh apps. (default: None)

See DocumentChangedEvent for more details.
callback_invoker (callable, optional) – A callable that will invoke any Model callbacks that should be executed in response to the change that triggered this event. (default: None)

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._column_data_changed if it exists.

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

{
    'kind'          : 'ColumnDataChanged'
    'column_source' : <reference to a CDS>
    'new'           : <new data to steam to column_source>
    'cols'          : <specific columns to update>
}

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.

class ColumnsPatchedEvent(document, column_source, patches, setter=None, callback_invoker=None)[source]¶

A concrete event representing efficiently applying data patches to a ColumnDataSource

__init__(document, column_source, patches, setter=None, callback_invoker=None)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
column_source (ColumnDataSource) – The data source to apply patches to.
patches (list) –
setter (ClientSession or ServerSession or None, optional) –
This is used to prevent “boomerang” updates to Bokeh apps. (default: None)

See DocumentChangedEvent for more details.
callback_invoker (callable, optional) – A callable that will invoke any Model callbacks that should be executed in response to the change that triggered this event. (default: None)

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._columns_patched if it exists.

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

{
    'kind'          : 'ColumnsPatched'
    'column_source' : <reference to a CDS>
    'patches'       : <patches to apply to column_source>
}

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.

class ColumnsStreamedEvent(document, column_source, data, rollover, setter=None, callback_invoker=None)[source]¶

A concrete event representing efficiently streaming new data to a ColumnDataSource

__init__(document, column_source, data, rollover, setter=None, callback_invoker=None)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
column_source (ColumnDataSource) – The data source to stream new data to.
data (dict or DataFrame) –
New data to stream.

If a DataFrame, will be stored as {c: df[c] for c in df.columns}
rollover (int) – A rollover limit. If the data source columns exceed this limit, earlier values will be discarded to maintain the column length under the limit.
setter (ClientSession or ServerSession or None, optional) –
This is used to prevent “boomerang” updates to Bokeh apps. (default: None)

See DocumentChangedEvent for more details.
callback_invoker (callable, optional) – A callable that will invoke any Model callbacks that should be executed in response to the change that triggered this event. (default: None)

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._columns_streamed if it exists.

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

{
    'kind'          : 'ColumnsStreamed'
    'column_source' : <reference to a CDS>
    'data'          : <new data to steam to column_source>
    'rollover'      : <rollover limit>
}

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.

class DocumentChangedEvent(document, setter=None, callback_invoker=None)[source]¶

Base class for all internal events representing a change to a Bokeh Document.

__init__(document, setter=None, callback_invoker=None)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
setter (ClientSession or ServerSession or None, optional) –
This is used to prevent “boomerang” updates to Bokeh apps. (default: None)

In the context of a Bokeh server application, incoming updates to properties will be annotated with the session that is doing the updating. This value is propagated through any subsequent change notifications that the update triggers. The session can compare the event setter to itself, and suppress any updates that originate from itself.
callback_invoker (callable, optional) – A callable that will invoke any Model callbacks that should be executed in response to the change that triggered this event. (default: None)

combine(event)[source]¶

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._document_changed if it exists.

class DocumentPatchedEvent(document, setter=None, callback_invoker=None)[source]¶

A Base class for events that represent updating Bokeh Models and their properties.

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._document_patched if it exists.

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

Sub-classes must implement this method.

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.

class MessageSentEvent(document, msg_type: str, msg_data: Union[Any, bytes], setter=None, callback_invoker=None)[source]¶

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._document_patched if it exists.

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

Sub-classes must implement this method.

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.

class ModelChangedEvent(document, model, attr, old, new, serializable_new, hint=None, setter=None, callback_invoker=None)[source]¶

A concrete event representing updating an attribute and value of a specific Bokeh Model.

This is the “standard” way of updating most Bokeh model attributes. For special casing situations that can optimized (e.g. streaming, etc.), a hint may be supplied that overrides normal mechanisms.

__init__(document, model, attr, old, new, serializable_new, hint=None, setter=None, callback_invoker=None)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
model (Model) – A Model to update
attr (str) – The name of the attribute to update on the model.
old (object) – The old value of the attribute
new (object) – The new value of the attribute
serializable_new (object) – A serialized (JSON) version of the new value. It may be None if a hint is supplied.
hint (DocumentPatchedEvent, optional) – When appropriate, a secondary event may be supplied that modifies the normal update process. For example, in order to stream or patch data more efficiently than the standard update mechanism.
setter (ClientSession or ServerSession or None, optional) –
This is used to prevent “boomerang” updates to Bokeh apps. (default: None)

See DocumentChangedEvent for more details.
callback_invoker (callable, optional) – A callable that will invoke any Model callbacks that should be executed in response to the change that triggered this event. (default: None)

combine(event)[source]¶

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._document_model_changed if it exists.

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.

class RootAddedEvent(document, model, setter=None, callback_invoker=None)[source]¶

A concrete event representing a change to add a new Model to a Document’s collection of “root” models.

__init__(document, model, setter=None, callback_invoker=None)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
model (Model) – The Bokeh Model to add as a Document root.
setter (ClientSession or ServerSession or None, optional) –
This is used to prevent “boomerang” updates to Bokeh apps. (default: None)

See DocumentChangedEvent for more details.
callback_invoker (callable, optional) – A callable that will invoke any Model callbacks that should be executed in response to the change that triggered this event. (default: None)

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

{
    'kind'  : 'RootAdded'
    'title' : <reference to a Model>
}

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.

class RootRemovedEvent(document, model, setter=None, callback_invoker=None)[source]¶

A concrete event representing a change to remove an existing Model from a Document’s collection of “root” models.

__init__(document, model, setter=None, callback_invoker=None)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
model (Model) – The Bokeh Model to remove as a Document root.
setter (ClientSession or ServerSession or None, optional) –
This is used to prevent “boomerang” updates to Bokeh apps. (default: None)

See DocumentChangedEvent for more details.
callback_invoker (callable, optional) – A callable that will invoke any Model callbacks that should be executed in response to the change that triggered this event. (default: None)

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

{
    'kind'  : 'RootRemoved'
    'title' : <reference to a Model>
}

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.

class SessionCallbackAdded(document, callback)[source]¶

A concrete event representing a change to add a new callback (e.g. periodic, timeout, or “next tick”) to a Document.

__init__(document, callback)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
callback (SessionCallback) – The callback to add

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._session_callback_added if it exists.

class SessionCallbackRemoved(document, callback)[source]¶

A concrete event representing a change to remove an existing callback (e.g. periodic, timeout, or “next tick”) from a Document.

__init__(document, callback)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
callback (SessionCallback) – The callback to remove

dispatch(receiver)[source]¶

Dispatch handling of this event to a receiver.

This method will invoke receiver._session_callback_removed if it exists.

class TitleChangedEvent(document, title, setter=None, callback_invoker=None)[source]¶

A concrete event representing a change to the title of a Bokeh Document.

__init__(document, title, setter=None, callback_invoker=None)[source]¶

Parameters

document (Document) – A Bokeh document that is to be updated.
title (str) – The new title to set on the Document
setter (ClientSession or ServerSession or None, optional) –
This is used to prevent “boomerang” updates to Bokeh apps. (default: None)

See DocumentChangedEvent for more details.
callback_invoker (callable, optional) – A callable that will invoke any Model callbacks that should be executed in response to the change that triggered this event. (default: None)

combine(event)[source]¶

generate(references, buffers)[source]¶

Create a JSON representation of this event suitable for sending to clients.

{
    'kind'  : 'TitleChanged'
    'title' : <new title to set>
}

Parameters

references (dict[str, Model]) –
If the event requires references to certain models in order to function, they may be collected here.

This is an “out” parameter. The values it contains will be modified in-place.
buffers (set) –
If the event needs to supply any additional Bokeh protocol buffers, they may be added to this set.

This is an “out” parameter. The values it contains will be modified in-place.