Fixes for jslinking HoloViews components (#3165)

panel/io/datamodel.py

@@ -88,10 +88,10 @@ def list_param_to_ppt(p, kwargs):
     pm.Integer: lambda p, kwargs: bp.Int(**kwargs),
     pm.List: list_param_to_ppt,
     pm.Number: lambda p, kwargs: bp.Float(**kwargs),
-    pm.NumericTuple: lambda p, kwargs: bp.Tuple(*(bp.Float for p in p.length), **kwargs),
+    pm.NumericTuple: lambda p, kwargs: bp.Tuple(*(bp.Float for p in range(p.length)), **kwargs),
     pm.Range: lambda p, kwargs: bp.Tuple(bp.Float, bp.Float, **kwargs),
     pm.String: lambda p, kwargs: bp.String(**kwargs),
-    pm.Tuple: lambda p, kwargs: bp.Tuple(*(bp.Any for p in p.length), **kwargs),
+    pm.Tuple: lambda p, kwargs: bp.Tuple(*(bp.Any for p in range(p.length)), **kwargs),
 }
 
 

panel/links.py

@@ -1,18 +1,78 @@
 """
 Defines Links which allow declaring links between bokeh properties.
 """
-import param
-import weakref
+import difflib
 import sys
+import weakref
+
+import param
 
-from bokeh.models import CustomJS, Model as BkModel
+from bokeh.models import CustomJS, Model as BkModel, LayoutDOM
 
 from .io.datamodel import create_linked_datamodel
 from .models import ReactiveHTML
 from .reactive import Reactive
 from .viewable import Viewable
 
 
+def assert_source_syncable(source, properties):
+    for prop in properties:
+        if prop.startswith('event:'):
+            continue
+        elif hasattr(source, 'object') and isinstance(source.object, LayoutDOM):
+            current = source.object
+            for attr in prop.split('.'):
+                if hasattr(current, attr):
+                    current = getattr(current, attr)
+                    continue
+                raise ValueError(
+                    f"Could not resolve {prop} on {source.object} model. "
+                    "Ensure you jslink an attribute that exists on the "
+                    "bokeh model."
+                )
+        elif (prop not in source.param and prop not in list(source._rename.values())):
+            matches = difflib.get_close_matches(prop, list(source.param))
+            if matches:
+                matches = f' Similar parameters include: {matches!r}'
+            else:
+                matches = ''
+            raise ValueError(
+                f"Could not jslink {prop!r} parameter (or property) "
+                f"on {type(source).__name__} object because it was not "
+                "found.{matches}."
+            )
+        elif (source._source_transforms.get(prop, False) is None or
+              source._rename.get(prop, False) is None):
+            raise ValueError(
+                f"Cannot jslink {prop!r} parameter on {type(source).__name__} "
+                "object, the parameter requires a live Python kernel "
+                "to have an effect."
+            )
+
+def assert_target_syncable(source, target, properties):
+    for k, p in properties.items():
+        if k.startswith('event:'):
+            continue
+        elif p not in target.param and p not in list(target._rename.values()):
+            matches = difflib.get_close_matches(p, list(target.param))
+            if matches:
+                matches = ' Similar parameters include: %r' % matches
+            else:
+                matches = ''
+            raise ValueError(
+                f"Could not jslink {p!r} parameter (or property) "
+                f"on {type(source).__name__} object because it was not "
+                "found. Similar parameters include: {matches}"
+            )
+        elif (target._source_transforms.get(p, False) is None or
+              target._rename.get(p, False) is None):
+            raise ValueError(
+                f"Cannot jslink {k!r} parameter on {type(source).__name__} "
+                f"object to {p!r} parameter on {type(target).__name__}. "
+                "It requires a live Python kernel to have an effect."
+            )
+
+
 class Callback(param.Parameterized):
     """
     A Callback defines some callback to be triggered when a property
@@ -102,7 +162,12 @@ def _process_callbacks(cls, root_view, root_model):
 
         arg_overrides = {}
         if 'holoviews' in sys.modules:
+            from holoviews.core.dimension import Dimensioned
             from .pane.holoviews import HoloViews, generate_panel_bokeh_map
+            found = [
+                (link, src, tgt) for (link, src, tgt) in found
+                if not (isinstance(src, Dimensioned) or isinstance(tgt, Dimensioned))
+            ]
             hv_views = root_view.select(HoloViews)
             map_hve_bk = generate_panel_bokeh_map(root_model, hv_views)
             for src in linkable:
@@ -276,7 +341,8 @@ def _init_callback(self, root_model, link, source, src_spec, target, tgt_spec, c
 
         src_model = self._resolve_model(root_model, source, src_spec[0])
         ref = root_model.ref['id']
-        link_id = id(link)
+
+        link_id = (id(link), src_spec, tgt_spec)
         if (any(link_id in cb.tags for cbs in src_model.js_property_callbacks.values() for cb in cbs) or
             any(link_id in cb.tags for cbs in src_model.js_event_callbacks.values() for cb in cbs)):
             # Skip registering callback if already registered

panel/pane/holoviews.py

@@ -335,6 +335,23 @@ def applies(cls, obj):
         from holoviews.plotting.plot import Plot
         return isinstance(obj, Dimensioned) or isinstance(obj, Plot)
 
+    def jslink(self, target, code=None, args=None, bidirectional=False, **links):
+        if links and code:
+            raise ValueError('Either supply a set of properties to '
+                             'link as keywords or a set of JS code '
+                             'callbacks, not both.')
+        elif not links and not code:
+            raise ValueError('Declare parameters to link or a set of '
+                             'callbacks, neither was defined.')
+        if args is None:
+            args = {}
+
+        from ..links import Link
+        return Link(self, target, properties=links, code=code, args=args,
+                    bidirectional=bidirectional)
+
+    jslink.__doc__ = PaneBase.jslink.__doc__
+
     @classmethod
     def widgets_from_dimensions(cls, object, widget_types=None, widgets_type='individual'):
         from holoviews.core import Dimension, DynamicMap

panel/reactive.py

@@ -17,7 +17,6 @@
 import numpy as np
 import param
 
-from bokeh.models import LayoutDOM
 from bokeh.model import DataModel
 from param.parameterized import ParameterizedMetaclass, Watcher
 
@@ -561,55 +560,11 @@ def jslink(self, target, code=None, args=None, bidirectional=False, **links):
         if args is None:
             args = {}
 
+        from .links import Link, assert_source_syncable, assert_target_syncable
         mapping = code or links
-        for k in mapping:
-            if k.startswith('event:'):
-                continue
-            elif hasattr(self, 'object') and isinstance(self.object, LayoutDOM):
-                current = self.object
-                for attr in k.split('.'):
-                    if not hasattr(current, attr):
-                        raise ValueError(f"Could not resolve {k} on "
-                                         f"{self.object} model. Ensure "
-                                         "you jslink an attribute that "
-                                         "exists on the bokeh model.")
-                    current = getattr(current, attr)
-            elif (k not in self.param and k not in list(self._rename.values())):
-                matches = difflib.get_close_matches(k, list(self.param))
-                if matches:
-                    matches = ' Similar parameters include: %r' % matches
-                else:
-                    matches = ''
-                raise ValueError("Could not jslink %r parameter (or property) "
-                                 "on %s object because it was not found.%s"
-                                 % (k, type(self).__name__, matches))
-            elif (self._source_transforms.get(k, False) is None or
-                  self._rename.get(k, False) is None):
-                raise ValueError("Cannot jslink %r parameter on %s object, "
-                                 "the parameter requires a live Python kernel "
-                                 "to have an effect." % (k, type(self).__name__))
-
+        assert_source_syncable(self, mapping)
         if isinstance(target, Syncable) and code is None:
-            for k, p in mapping.items():
-                if k.startswith('event:'):
-                    continue
-                elif p not in target.param and p not in list(target._rename.values()):
-                    matches = difflib.get_close_matches(p, list(target.param))
-                    if matches:
-                        matches = ' Similar parameters include: %r' % matches
-                    else:
-                        matches = ''
-                    raise ValueError("Could not jslink %r parameter (or property) "
-                                     "on %s object because it was not found.%s"
-                                    % (p, type(self).__name__, matches))
-                elif (target._source_transforms.get(p, False) is None or
-                      target._rename.get(p, False) is None):
-                    raise ValueError("Cannot jslink %r parameter on %s object "
-                                     "to %r parameter on %s object. It requires "
-                                     "a live Python kernel to have an effect."
-                                     % (k, type(self).__name__, p, type(target).__name__))
-
-        from .links import Link
+            assert_target_syncable(self, target, mapping)
         return Link(self, target, properties=links, code=code, args=args,
                     bidirectional=bidirectional)
 

panel/tests/test_links.py

@@ -82,8 +82,7 @@ def test_widget_link_no_target_transform_error():
 
     with pytest.raises(ValueError) as excinfo:
         t2.jslink(t1, value='value')
-    assert ("Cannot jslink \'value\' parameter on TextInput object "
-            "to \'value\' parameter on DatetimeInput object") in str(excinfo)
+    assert ("Cannot jslink 'value' parameter on TextInput object to 'value' parameter on DatetimeInput") in str(excinfo)
 
 
 @hv_available