Render map_index_template when the task status is set manually

[karenbraganz]

Render map_index_template when task status is manually set

I made render_map_index a class method in task_instance.py and called it in the set_task_instance_state method in dag.py. I am currently working on debugging the following exception in my code which happens when the self.rendered_map_index = jinja_env.from_string(template).render(context) statement is executed (when render_map_index method from taskinstance.py is called).

As of now, my code is aimed at rendering the map_index_template when an individual mapped task instance is marked "succes" in the UI. Once I am able to get this working, I will change it so that it also can render the map_index_template of all mapped task instances when the entire task instance is marked as success. To replicate the exception I am seeing, do the following:

1. Create a DAG with a mapped task (I used the example in the issue)
2. Trigger it in the UI
3. Navigate to the task instance square in grid view
4. Navigate to the Mapped Tasks[] tab
5. Click on one of the mapped task instances that is not already running
6. Use the blue "Mark state as..." button on the top right to mark the mapped task instance state as "success"

Please note that this exception only happens when the state is manually set, not when the task executes automatically. Hence, the changes don't affect current functionality.

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[boring-cyborg]

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[uranusjr]

This runs the Jinja template in the webserver. I don’t think it is viable.

[karenbraganz]

@uranusjr could you please clarify why rendering the template on the webserver is not viable? Thanks.