Dags in Airflow UI do not show on/off and keep on loading

Question

I installed airflow using Kubernetes and have login the airflow UI. It shows all dags, but they are not shown correctly.

1/ There is no on/off buttons on the left of Dag name, it just show empty checkbox.

2/ The "Recent Tasks" and "DAG Runs" columns look like they are trying to load something;

3/ If I click and therefore go to any of DAG, it looks like it tries to load something;

I tried both airflow 2.0.0 and 1.10.11 and they show the same so it is not because of version.

What is the problem of the airflow and how to fix that?

------- here I provide more information according to Ofek Hod's suggestion: 1/ run "kubectl logs <pod_id> webserver", after I login airflow web UI, I got many http 404 response. e.g.

after I click any dag in airflow WebUI I got some other 404 response

Answer 1

find the answer myself:

The package I use to setup k8s-airflow has a step to run ./airflow/www/compile_assets.sh using npm but the package missed the step to install npm. so I added "apt install -y npm" in the step and now I see airflow page correctly.

Answer 2

Airflow interprets all your .py files in your dags folder first, I guess something goes wrong there.
As a rule-of-thumb, first access webserver and scheduler logs (for kub kubectl logs?), maybe you can find a hint there.

If not, try first to make a "clean" airflow instance without any of your dags code or related .py files- point the dags folder to an empty directory and see what happens (better if you turn on example dags configuration).

If that works, add your .py files from the original dag folder incrementally until you find problematic code.

If it's not working, probably the scheduler or webserver are messed up, please check the logs again with better attention.