Fix compatibility with bokeh 2.4 DocumentCallbackManager

panel/io/model.py

@@ -9,6 +9,7 @@
 from bokeh.models import Box, ColumnDataSource, Model
 from bokeh.protocol import Protocol
 
+from ..util import bokeh_version
 from .state import state
 
 #---------------------------------------------------------------------
@@ -20,6 +21,11 @@ def diff(doc, binary=True, events=None):
     Returns a json diff required to update an existing plot with
     the latest plot data.
     """
+    if events is None:
+        if bokeh_version >= '2.4':
+            events = list(doc.callbacks._held_events)
+        else:
+            events = list(doc._held_events)
     events = list(doc._held_events) if events is None else events
     if not events or state._hold:
         return None
@@ -54,12 +60,19 @@ def add_to_doc(obj, doc, hold=False):
     # Add new root
     remove_root(obj)
     doc.add_root(obj)
-    if doc._hold is None and hold:
+    if bokeh_version >= '2.4':
+        doc_hold = doc.callbacks.hold_value
+    else:
+        doc_hold = doc._hold
+    if doc_hold is None and hold:
         doc.hold()
 
 @contextmanager
 def hold(doc, policy='combine', comm=None):
-    held = doc._hold
+    if bokeh_version >= '2.4':
+        held = doc.callbacks.hold_value
+    else:
+        held = doc._hold
     try:
         if policy is None:
             doc.unhold()
@@ -68,7 +81,10 @@ def hold(doc, policy='combine', comm=None):
         yield
     finally:
         if held:
-            doc._hold = held
+            if bokeh_version >= '2.4':
+                doc.callbacks._hold = held
+            else:
+                doc._hold = held
         else:
             if comm is not None:
                 from .notebook import push

panel/io/server.py

@@ -446,7 +446,10 @@ def unlocked():
         return
     connections = curdoc.session_context.session._subscribed_connections
 
-    hold = curdoc._hold
+    if bokeh_version >= '2.4':
+        hold = curdoc.callbacks.hold_value
+    else:
+        hold = curdoc._hold
     if hold:
         old_events = list(curdoc._held_events)
     else:

panel/pane/plot.py

@@ -14,7 +14,7 @@
 
 from ..io import remove_root
 from ..io.notebook import push
-from ..util import escape
+from ..util import escape, bokeh_version
 from ..viewable import Layoutable
 from .base import PaneBase
 from .ipywidget import IPyWidget
@@ -32,7 +32,10 @@ def _wrap_callback(cb, wrapped, doc, comm, callbacks):
     replaces the wrapped callback with the real one while the callback
     is exectuted to ensure the callback can be removed as usual.
     """
-    hold = doc._hold
+    if bokeh_version >= '2.4':
+        hold = doc.callbacks.hold_value
+    else:
+        hold = doc._hold
     doc.hold('combine')
     if wrapped in callbacks:
         index = callbacks.index(wrapped)

panel/reactive.py

@@ -1487,7 +1487,7 @@ def _set_on_model(self, msg, root, model):
             model.update(**msg)
         finally:
             if old:
-                self._chaning[root.ref['id']] = old
+                self._changing[root.ref['id']] = old
             else:
                 del self._changing[root.ref['id']]
 

panel/viewable.py

@@ -32,7 +32,7 @@
 from .io.save import save
 from .io.state import state
 from .io.server import init_doc, serve
-from .util import escape, param_reprs
+from .util import bokeh_version, escape, param_reprs
 
 
 class Layoutable(param.Parameterized):
@@ -266,7 +266,10 @@ def _on_msg(self, ref, manager, msg):
         """
         root, doc, comm = state._views[ref][1:]
         patch_cds_msg(root, msg)
-        held = doc._hold
+        if bokeh_version >= '2.4':
+            hold = doc.callbacks.hold_value
+        else:
+            held = doc._hold
         patch = manager.assemble(msg)
         doc.hold()
         patch.apply_to_document(doc, comm.id)