Various fixes for resolution of links (#354)

panel/io/state.py

@@ -57,7 +57,7 @@ def curdoc(self, doc):
 
     @property
     def session_args(self):
-        return self.curdoc.session_context.arguments if self.curdoc else {}
+        return self.curdoc.session_context.request.arguments if self.curdoc else {}
 
 
 state = _state()

panel/layout.py

@@ -62,7 +62,11 @@ def _update_model(self, events, msg, root, model, doc, comm=None):
             old = events['objects'].old
             msg[self._rename['objects']] = self._get_objects(model, old, doc, root, comm)
         model.update(**msg)
-        self._preprocess(root) #preprocess links between new elements
+
+        from .io import state
+        ref = root.ref['id']
+        if ref in state._views:
+            state._views[ref][0]._preprocess(root)
 
     #----------------------------------------------------------------
     # Model API

panel/links.py

@@ -204,6 +204,10 @@ def _init_callback(self, root_model, link, source, src_spec, target, tgt_spec, c
                       if k not in ('source', 'target', 'name', 'code')}
 
         src_model = self._resolve_model(root_model, source, src_spec[0])
+        link_id = id(link)
+        if any(link_id in cb.tags for cbs in src_model.js_property_callbacks.values() for cb in cbs):
+            # Skip registering callback if already registered
+            return
         references['source'] = src_model
 
         tgt_model = self._resolve_model(root_model, target, tgt_spec[0])
@@ -226,7 +230,7 @@ def _init_callback(self, root_model, link, source, src_spec, target, tgt_spec, c
         if code is None:
             code = self._get_code(link, source, src_spec[1], target, tgt_spec[1])
 
-        src_cb = CustomJS(args=references, code=code)
+        src_cb = CustomJS(args=references, code=code, tags=[link_id])
         changes, events = self._get_triggers(link, src_spec)
         for ch in changes:
             src_model.js_on_change(ch, src_cb)

panel/param.py

@@ -580,6 +580,25 @@ def _get_model(self, doc, root=None, parent=None, comm=None):
         self._models[ref] = (model, parent)
         return model
 
+    def select(self, selector=None):
+        """
+        Iterates over the Viewable and any potential children in the
+        applying the Selector.
+
+        Arguments
+        ---------
+        selector: type or callable or None
+          The selector allows selecting a subset of Viewables by
+          declaring a type or callable function to filter by.
+
+        Returns
+        -------
+        viewables: list(Viewable)
+        """
+        selected = super(ParamMethod, self).select(selector)
+        selected += self._pane.select(selector)
+        return selected
+
     def _cleanup(self, root=None):
         self._inner_layout._cleanup(root)
         super(ParamMethod, self)._cleanup(root)