feat: add get_template_context() method for master view

allow override / supplement context for any view template

src/wuttaweb/views/master.py

@@ -1629,6 +1629,9 @@ class MasterView(View):
             if 'instance_deletable' not in context:
                 context['instance_deletable'] = self.is_deletable(instance)
 
+        # supplement context further if needed
+        context = self.get_template_context(context)
+
         # first try the template path most specific to this view
         template_prefix = self.get_template_prefix()
         mako_path = f'{template_prefix}/{template}.mako'
@@ -1648,6 +1651,26 @@ class MasterView(View):
             # let that error raise on up
             return render_to_response(mako_path, context, request=self.request)
 
+    def get_template_context(self, context):
+        """
+        This method should return the "complete" context for rendering
+        the current view template.
+
+        Default logic for this method returns the given context
+        unchanged.
+
+        You may wish to override to pass extra context to the view
+        template.  Check :attr:`viewing` and similar, or
+        ``request.current_route_name`` etc. in order to add extra
+        context only for certain view templates.
+
+        :params: context: The context dict we have so far,
+           auto-provided by the master view logic.
+
+        :returns: Final context dict for the template.
+        """
+        return context
+
     def get_fallback_templates(self, template):
         """
         Returns a list of "fallback" template paths which may be