Remove /dagrun/create and disable /dagrun/edit generated by F.A.B

[uranusjr]

This came up during a conversaion with @ashb. Currently we are exposing the ability to directly create and edit a DagRun instance via F.A.B.’s CRUD view generation (the plus and edit icons on the DagRun list view). But these views don’t really make a lot of sense; creating a DagRun requires doing more than just adding a DagRun instance to the database (which is why triggering a DAG run in the home view uses /trigger instead). The /dagrun/add view provides essentially a way to manually modify Airflow’s internal state. So this view is removed.

The story with /dagrun/edit is similar. The only thing on a DagRun that can be reasonably edited is the state (running, failed, skipped, etc.), but that should also do more things than just setting the state, which is why we have Mark Failed, Mark Success, and Clear action buttons. Unfortunately, we can’t remove the field since we need the can_edit permission for those state-setting action methods, so instead all fields in the edit form is disabled so the user can’t modify anything on the DagRun.

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[uranusjr]

Grr, so it seems F.A.B. does not allow disabling the edit form as long as there is an action that uses the edit permission (wtf). So we need to jump through some hoops for this. One workaround I can think of is to keep the edit view, but make all fields readonly.

[uranusjr]

OK, maybe this is good enough.