Issue 1:
Apache Airflow version

2.3.0 (latest released)

What happened

Dag processor failed to start if [core] sql_alchemy_conn not defined

airflow-local-airflow-dag-processor-1 | [2022-05-08 16:42:35,835] {configuration.py:494} WARNING - section/key [core/sql_alchemy_conn] not found in config
airflow-local-airflow-dag-processor-1 | Traceback (most recent call last):
airflow-local-airflow-dag-processor-1 | File "/home/airflow/.local/bin/airflow", line 8, in <module>
airflow-local-airflow-dag-processor-1 | sys.exit(main())
airflow-local-airflow-dag-processor-1 | File "/home/airflow/.local/lib/python3.9/site-packages/airflow/__main__.py", line 38, in main
airflow-local-airflow-dag-processor-1 | args.func(args)
airflow-local-airflow-dag-processor-1 | File "/home/airflow/.local/lib/python3.9/site-packages/airflow/cli/cli_parser.py", line 51, in command
airflow-local-airflow-dag-processor-1 | return func(*args, **kwargs)
airflow-local-airflow-dag-processor-1 | File "/home/airflow/.local/lib/python3.9/site-packages/airflow/utils/cli.py", line 99, in wrapper
airflow-local-airflow-dag-processor-1 | return f(*args, **kwargs)
airflow-local-airflow-dag-processor-1 | File "/home/airflow/.local/lib/python3.9/site-packages/airflow/cli/commands/dag_processor_command.py", line 53, in dag_processor
airflow-local-airflow-dag-processor-1 | sql_conn: str = conf.get('core', 'sql_alchemy_conn').lower()
airflow-local-airflow-dag-processor-1 | File "/home/airflow/.local/lib/python3.9/site-packages/airflow/configuration.py", line 486, in get
airflow-local-airflow-dag-processor-1 | return self._get_option_from_default_config(section, key, **kwargs)
airflow-local-airflow-dag-processor-1 | File "/home/airflow/.local/lib/python3.9/site-packages/airflow/configuration.py", line 496, in _get_option_from_default_config
airflow-local-airflow-dag-processor-1 | raise AirflowConfigException(f"section/key [{section}/{key}] not found in config")
airflow-local-airflow-dag-processor-1 | airflow.exceptions.AirflowConfigException: section/key [core/sql_alchemy_conn] not found in config

What you think should happen instead

Since #22284 sql_alchemy_conn moved to [database] section dag-processor should use this configuration

How to reproduce

Run airflow dag-processor without defined [core] sql_alchemy_conn

airflow/airflow/cli/commands/dag_processor_command.py

Lines 52 to 53
in
6e59558

sql_conn: str = conf.get('core', 'sql_alchemy_conn').lower()

Operating System

Arch Linux

Versions of Apache Airflow Providers

apache-airflow-providers-amazon==3.3.0
apache-airflow-providers-celery==2.1.4
apache-airflow-providers-cncf-kubernetes==4.0.1
apache-airflow-providers-docker==2.6.0
apache-airflow-providers-elasticsearch==3.0.3
apache-airflow-providers-ftp==2.1.2
apache-airflow-providers-google==6.8.0
apache-airflow-providers-grpc==2.0.4
apache-airflow-providers-hashicorp==2.2.0
apache-airflow-providers-http==2.1.2
apache-airflow-providers-imap==2.2.3
apache-airflow-providers-microsoft-azure==3.8.0
apache-airflow-providers-mysql==2.2.3
apache-airflow-providers-odbc==2.0.4
apache-airflow-providers-postgres==4.1.0
apache-airflow-providers-redis==2.0.4
apache-airflow-providers-sendgrid==2.0.4
apache-airflow-providers-sftp==2.6.0
apache-airflow-providers-slack==4.2.3
apache-airflow-providers-snowflake==2.6.0
apache-airflow-providers-sqlite==2.1.3
apache-airflow-providers-ssh==2.4.3

Deployment

Docker-Compose

Deployment details

No response

Anything else

No response

Are you willing to submit PR?

Yes I am willing to submit a PR!

Code of Conduct

I agree to follow this project's Code of Conduct

Issue 2:
Apache Airflow version

2.3.0 (latest released)

What happened

Running a standalone Dag Processor instance with airflow dag-processor throws the following exception:

Standalone DagProcessor is not supported when using sqlite.

What you think should happen instead

The airflow dag-processor should start without an exception in case of Postgres database

How to reproduce

The error is in the following line:

airflow/airflow/cli/commands/dag_processor_command.py

Line 53
in
6f146e7

sql_conn: str = conf.get('core', 'sql_alchemy_conn').lower()

It should be

sql_conn: str = conf.get('database', 'sql_alchemy_conn').lower()

due to the change in the configuration file done in #22284

Operating System

Ubuntu 20.04

Versions of Apache Airflow Providers

No response

Deployment

Virtualenv installation

Deployment details

No response

Anything else

No response

Are you willing to submit PR?

Yes I am willing to submit a PR!

Code of Conduct

I agree to follow this project's Code of Conduct