Improve form support for view supplements

this seems a bit hacky yet but works for now..

cf. field logic for Vendor -> Quickbooks Bank Accounts, which requires this

tailbone/forms/core.py

@@ -338,7 +338,7 @@ class Form(object):
                  assume_local_times=False, renderers=None, renderer_kwargs={},
                  hidden={}, widgets={}, defaults={}, validators={}, required={}, helptext={}, focus_spec=None,
                  action_url=None, cancel_url=None, component='tailbone-form',
-                 vuejs_component_kwargs=None, vuejs_field_converters={},
+                 vuejs_component_kwargs=None, vuejs_field_converters={}, json_data={}, included_templates={},
                  # TODO: ugh this is getting out hand!
                  can_edit_help=False, edit_help_url=None, route_prefix=None,
     ):
@@ -381,6 +381,8 @@ class Form(object):
         self.component = component
         self.vuejs_component_kwargs = vuejs_component_kwargs or {}
         self.vuejs_field_converters = vuejs_field_converters or {}
+        self.json_data = json_data or {}
+        self.included_templates = included_templates or {}
         self.can_edit_help = can_edit_help
         self.edit_help_url = edit_help_url
         self.route_prefix = route_prefix
@@ -966,6 +968,30 @@ class Form(object):
             kwargs.setdefault(':configure-fields-help', 'configureFieldsHelp')
         return HTML.tag(self.component, **kwargs)
 
+    def set_json_data(self, key, value):
+        """
+        Establish a data value for use in client-side JS.  This value
+        will be JSON-encoded and made available to the
+        `<tailbone-form>` component within the client page.
+        """
+        self.json_data[key] = value
+
+    def include_template(self, template, context):
+        """
+        Declare a JS template as required by the current form.  This
+        template will then be included in the final page, so all
+        widgets behave correctly.
+        """
+        self.included_templates[template] = context
+
+    def render_included_templates(self):
+        templates = []
+        for template, context in self.included_templates.items():
+            context = dict(context)
+            context['form'] = self
+            templates.append(HTML.literal(render(template, context)))
+        return HTML.literal('\n').join(templates)
+
     def render_field_complete(self, fieldname, bfield_attrs={}):
         """
         Render the given field completely, i.e. with ``<b-field>``

tailbone/templates/master/form.mako

@@ -3,17 +3,26 @@
 
 <%def name="modify_this_page_vars()">
   ${parent.modify_this_page_vars()}
-  % if master.deletable and instance_deletable and request.has_perm('{}.delete'.format(permission_prefix)) and master.delete_confirm == 'simple':
   <script type="text/javascript">
 
+    ## declare extra data needed by form
+    % for key, value in form.json_data.items():
+        ${form.component_studly}Data.${key} = ${json.dumps(value)|n}
+    % endfor
+
+    % if master.deletable and instance_deletable and master.has_perm('delete') and master.delete_confirm == 'simple':
+
         ThisPage.methods.deleteObject = function() {
             if (confirm("Are you sure you wish to delete this ${model_title}?")) {
                 this.$refs.deleteObjectForm.submit()
             }
         }
 
-      </script>
     % endif
+  </script>
+
+  ${form.render_included_templates()}
+
 </%def>
 
 

tailbone/views/master.py

@@ -2695,8 +2695,15 @@ class MasterView(View):
 
         context.update(data)
         context.update(self.template_kwargs(**context))
-        if hasattr(self, 'template_kwargs_{}'.format(template)):
-            context.update(getattr(self, 'template_kwargs_{}'.format(template))(**context))
+
+        method_name = f'template_kwargs_{template}'
+        if hasattr(self, method_name):
+            context.update(getattr(self, method_name)(**context))
+        for supp in self.iter_view_supplements():
+            if hasattr(supp, 'template_kwargs'):
+                context.update(getattr(supp, 'template_kwargs')(**context))
+            if hasattr(supp, method_name):
+                context.update(getattr(supp, method_name)(**context))
 
         # First try the template path most specific to the view.
         mako_path = '{}/{}.mako'.format(self.get_template_prefix(), template)
@@ -4441,6 +4448,9 @@ class MasterView(View):
             if not self.has_perm('view_global'):
                 obj.local_only = True
 
+        for supp in self.iter_view_supplements():
+            obj = supp.objectify(obj, form, data)
+
         return obj
 
     def objectify_contact(self, contact, data):
@@ -5892,6 +5902,9 @@ class ViewSupplement(object):
         renderers, default values etc. for them.
         """
 
+    def objectify(self, obj, form, data):
+        return obj
+
     def get_xref_buttons(self, obj):
         return []