Issue 1:
Apache Airflow version: 2.0.1

Kubernetes version (if you are using kubernetes) (use kubectl version):

Environment:

Cloud provider or hardware configuration: Dell Latitude

OS (e.g. from /etc/os-release): Ubuntu 20.04.2 LTS

Kernel (e.g. uname -a): 5.8.0-48-generic #54~20.04.1-Ubuntu SMP Sat Mar 20 13:40:25 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

Install tools: python 3.8.5

Others: local development

What happened: When I click delete button (on UI admin panel) for the DAG, admin panel crashed

Traceback (most recent call last):

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/flask/app.py", line 2447, in wsgi_app

response = self.full_dispatch_request()

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/flask/app.py", line 1952, in full_dispatch_request

rv = self.handle_user_exception(e)

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/flask/app.py", line 1821, in handle_user_exception

reraise(exc_type, exc_value, tb)

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/flask/_compat.py", line 39, in reraise

raise value

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/flask/app.py", line 1950, in full_dispatch_request

rv = self.dispatch_request()

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/flask/app.py", line 1936, in dispatch_request

return self.view_functionsrule.endpoint

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/airflow/www/auth.py", line 34, in decorated

return func(*args, **kwargs)

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/airflow/www/decorators.py", line 60, in wrapper

return f(*args, **kwargs)

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/airflow/www/views.py", line 1393, in delete

delete_dag.delete_dag(dag_id)

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/airflow/utils/session.py", line 65, in wrapper

return func(*args, session=session, **kwargs)

File "/home/krzysztofwrobel/.local/lib/python3.8/site-packages/airflow/api/common/experimental/delete_dag.py", line 54, in delete_dag

for model in models.base.Base._decl_class_registry.values(): # noqa pylint: disable=protected-access

AttributeError: type object 'Base' has no attribute '_decl_class_registry

What you expected to happen: Delete DAG

How to reproduce it: Try to delete dag in admin panel

Anything else we need to know:

Issue 2:
Body

I have a kind request for all the contributors to the latest provider packages release.

Could you please help us to test the RC versions of the providers?

Let us know in the comment, whether the issue is addressed.

Those are providers that require testing as there were some substantial changes introduced:

Provider amazon: 8.0.0rc3

Remove deprecated "delegate_to" from GCP operators and hooks (#30748): @shahar1

take advantage of upcoming major version release to remove deprecated things (#30755): @vandonr-amz

add a stop operator to emr serverless (#30720): @vandonr-amz

SqlToS3Operator - Add feature to partition SQL table (#30460): @utkarsharma2

New AWS sensor — DynamoDBValueSensor (#28338): @mrichman

Add a "force" option to emr serverless stop/delete operator (#30757): @vandonr-amz

Add support for deferrable operators in AMPP (#30032): @syedahsn

Fixed logging issue in DynamoDBValueSensor (#30703): @mrichman

DynamoDBHook - waiter_path() to consider resource_type or client_type (#30595): @utkarsharma2

Add ability to override waiter delay in EcsRunTaskOperator (#30586): @vincbeck

Add support in AWS Batch Operator for multinode jobs (#29522): @vandonr-amz

AWS logs. Exit fast when 3 consecutive responses are returned from AWS Cloudwatch logs (#30756): @vincbeck

Fix async conn for none aws_session_token (#30868): @pankajastro

Remove @poke_mode_only from EmrStepSensor (#30774): @vincbeck

Organize Amazon provider docs index (#30541): @eladkal

Remove duplicate param docstring in EksPodOperator (#30634): @jlaneve

Update AWS EMR Cluster Link to use the new dashboard (#30844): @dakshin-k

Restore aiobotocore as optional dependency of amazon provider (#30874): @potiuk

The guidelines on how to test providers can be found in

Verify providers by contributors

I have marked issues that were tested in RC2 as completed.

All users involved in the PRs:

@vincbeck @utkarsharma2 @syedahsn @mrichman @shahar1 @vandonr-amz @eladkal @potiuk @jlaneve @pankajastro @dakshin-k

Committer

I acknowledge that I am a maintainer/committer of the Apache Airflow project.