execution_date jinja resolving as a string - airflow

Question

I have an airflow dag that uses the following jinja template: "{{ execution_date.astimezone('Etc/GMT+6').subtract(days=1).strftime('%Y-%m-%dT00:00:00') }}"
This template works in other dags, and it works when the schedule_interval for the dag is set to timedelta(hours=1). However, when we set the schedule interval to 0 8 * * *, it throws the following traceback at runtime:
Traceback (most recent call last):
File "/usr/lib/python2.7/site-packages/airflow/models/__init__.py", line 1426, in _run_raw_task
self.render_templates()
File "/usr/lib/python2.7/site-packages/airflow/models/__init__.py", line 1790, in render_templates
rendered_content = rt(attr, content, jinja_context)
File "/usr/lib/python2.7/site-packages/airflow/models/__init__.py", line 2538, in render_template
return self.render_template_from_field(attr, content, context, jinja_env)
File "/usr/lib/python2.7/site-packages/airflow/models/__init__.py", line 2520, in render_template_from_field
for k, v in list(content.items())}
File "/usr/lib/python2.7/site-packages/airflow/models/__init__.py", line 2520, in <dictcomp>
for k, v in list(content.items())}
File "/usr/lib/python2.7/site-packages/airflow/models/__init__.py", line 2538, in render_template
return self.render_template_from_field(attr, content, context, jinja_env)
File "/usr/lib/python2.7/site-packages/airflow/models/__init__.py", line 2514, in render_template_from_field
result = jinja_env.from_string(content).render(**context)
File "/usr/lib64/python2.7/site-packages/jinja2/environment.py", line 1008, in render
return self.environment.handle_exception(exc_info, True)
File "/usr/lib64/python2.7/site-packages/jinja2/environment.py", line 780, in handle_exception
reraise(exc_type, exc_value, tb)
File "<template>", line 1, in top-level template code
TypeError: astimezone() argument 1 must be datetime.tzinfo, not str
It appears the execution date being passed in is a string, not a datetime object; but I am only able to hit this error on this specific dag, and no others. I've tried deleting the dag entirely and recreating it with no luck.

Answer 1

Looks like astimezone(..) function is misbehaving, it expects a datetime.tzinfo while you are passing it an str argument ('Etc/GMT+6')
TypeError: astimezone() argument 1 must be datetime.tzinfo, not str
While I couldn't make the exact thing work, I believe following achieves pretty much the same effect as what you are trying
{{ execution_date.in_timezone("US/Eastern") - timedelta(days=1) }}
Recall that
execution_date macro is a Pendulum object
in_timezone(..) converts it into a datetime.datetime(..)
then we just add a datetime.timedelta(days=1) to it