Stop adding values to rendered templates UI when there is no dagrun (#…

…33516)

(cherry picked from commit d9814eb)

airflow/www/views.py

@@ -1446,6 +1446,8 @@ def rendered_templates(self, session):
         dag_run = dag.get_dagrun(execution_date=dttm, session=session)
         raw_task = dag.get_task(task_id).prepare_for_execution()
 
+        no_dagrun = False
+
         title = "Rendered Template"
         html_dict = {}
 
@@ -1458,6 +1460,7 @@ def rendered_templates(self, session):
             # database) for presentation only.
             ti = TaskInstance(raw_task, map_index=map_index)
             ti.dag_run = DagRun(dag_id=dag_id, execution_date=dttm)
+            no_dagrun = True
         else:
             ti = dag_run.get_task_instance(task_id=task_id, map_index=map_index, session=session)
             if ti:
@@ -1503,28 +1506,33 @@ def rendered_templates(self, session):
             content = getattr(task, template_field)
             renderer = task.template_fields_renderers.get(template_field, template_field)
             if renderer in renderers:
-                html_dict[template_field] = renderers[renderer](content)
+                html_dict[template_field] = renderers[renderer](content) if not no_dagrun else ""
             else:
-                html_dict[template_field] = Markup("<pre><code>{}</pre></code>").format(pformat(content))
+                html_dict[template_field] = Markup("<pre><code>{}</pre></code>").format(
+                    pformat(content) if not no_dagrun else ""
+                )
 
             if isinstance(content, dict):
                 if template_field == "op_kwargs":
                     for key, value in content.items():
                         renderer = task.template_fields_renderers.get(key, key)
                         if renderer in renderers:
-                            html_dict[".".join([template_field, key])] = renderers[renderer](value)
+                            html_dict[".".join([template_field, key])] = (
+                                renderers[renderer](value) if not no_dagrun else ""
+                            )
                         else:
                             html_dict[".".join([template_field, key])] = Markup(
                                 "<pre><code>{}</pre></code>"
-                            ).format(pformat(value))
+                            ).format(pformat(value) if not no_dagrun else "")
                 else:
                     for dict_keys in get_key_paths(content):
                         template_path = ".".join((template_field, dict_keys))
                         renderer = task.template_fields_renderers.get(template_path, template_path)
                         if renderer in renderers:
                             content_value = get_value_from_path(dict_keys, content)
-                            html_dict[template_path] = renderers[renderer](content_value)
-
+                            html_dict[template_path] = (
+                                renderers[renderer](content_value) if not no_dagrun else ""
+                            )
         return self.render_template(
             "airflow/ti_code.html",
             show_trigger_form_if_no_params=conf.getboolean("webserver", "show_trigger_form_if_no_params"),