Fix misleading error message when GitHook creation fails

[amoghrajesh]

Previously, when GitHook creation failed (take for example a simple case of git connection not found), the exception was caught and suppressed, allowing bundle initialization to proceed in a way, which was a facade. This led to a misleading error message later: "Connection {conn_id} doesn't have a host url" instead of the actual error.

I am making this change to ensure that exceptions propagate immediately during bundle creation with clear error messages. The DAG processor handles exceptions per-bundle, so one failing bundle doesn't prevent others from loading successfully.

For testing, use a config like this where git connection doesnt exist:

export AIRFLOW__DAG_PROCESSOR__DAG_BUNDLE_CONFIG_LIST='[
  {
    "name": "test-git-bundle",
    "classpath": "airflow.providers.git.bundles.git.GitDagBundle",
    "kwargs": {
      "tracking_ref": "main",
      "git_conn_id": "non_existent_connection"
    }
  },
  {
    "name": "local-bundle",
    "classpath": "airflow.dag_processing.bundles.local.LocalDagBundle",
    "kwargs": {
      "path": "/Users/amoghdesai/Documents/OSS/repos/airflow/files/test_dags",
      "refresh_interval": 0
    }
  }
]'

Before it looked like this:

2025-12-05T07:18:54.567663Z [error    ] Error initializing bundle test-git-bundle: Connection non_existent_connection doesn't have a host url [airflow.dag_processing.manager.DagFileProcessorManager] loc=manager.py:528
Traceback (most recent call last):
  File "/opt/airflow/airflow-core/src/airflow/dag_processing/manager.py", line 526, in _refresh_dag_bundles
    bundle.initialize()
  File "/opt/airflow/providers/git/src/airflow/providers/git/bundles/git.py", line 134, in initialize
    raise AirflowException(f"Connection {self.git_conn_id} doesn't have a host url")
airflow.sdk.exceptions.AirflowException: Connection non_existent_connection doesn't have a host url
2025-12-05T07:18:59.647017Z [error    ] Error initializing bundle test-git-bundle: Connection non_existent_connection doesn't have a host url [airflow.dag_processing.manager.DagFileProcessorManager] loc=manager.py:528
Traceback (most recent call last):
  File "/opt/airflow/airflow-core/src/airflow/dag_processing/manager.py", line 526, in _refresh_dag_bundles
    bundle.initialize()
  File "/opt/airflow/providers/git/src/airflow/providers/git/bundles/git.py", line 134, in initialize
    raise AirflowException(f"Connection {self.git_conn_id} doesn't have a host url")
airflow.sdk.exceptions.AirflowException: Connection non_existent_connection doesn't have a host url

Now it looks like this:

root@c435d9bb0884:/opt/airflow# airflow dag-processor
2025-12-05T08:45:11.600794Z [warning  ] Failed to convert value. Please check memray_trace_components key in profiling section. it must be one of scheduler, dag_processor, api, if not the value is ignored [airflow._shared.configuration.parser] loc=parser.py:1127
__file__='/files/plugins/triggera.py' loaded
__file__='/files/plugins/triggera_comprehensive.py' loaded
2025-12-05T08:45:12.101992Z [info     ] Starting the Dag Processor Job [airflow.jobs.dag_processor_job_runner.DagProcessorJobRunner] loc=dag_processor_job_runner.py:59
2025-12-05T08:45:12.102262Z [info     ] Processing files using up to 2 processes at a time  [airflow.dag_processing.manager.DagFileProcessorManager] loc=manager.py:266
2025-12-05T08:45:12.102305Z [info     ] Process each file at most once every 30 seconds [airflow.dag_processing.manager.DagFileProcessorManager] loc=manager.py:267
2025-12-05T08:45:12.168422Z [info     ] DAG bundles loaded: test-git-bundle, local-bundle [airflow.dag_processing.bundles.manager.DagBundlesManager] loc=manager.py:209
2025-12-05T08:45:12.174930Z [error    ] Could not create GitHook       [airflow.providers.git.bundles.git] bare_repo_path=PosixPath('/tmp/airflow/dag_bundles/test-git-bundle/bare') bundle_name=test-git-bundle conn_id=non_existent_connection exc=AirflowNotFoundException("The conn_id `non_existent_connection` isn't defined") git_conn_id=non_existent_connection loc=git.py:94 repo_path=PosixPath('/tmp/airflow/dag_bundles/test-git-bundle/tracking_repo') version=None versions_path=PosixPath('/tmp/airflow/dag_bundles/test-git-bundle/versions')
Traceback (most recent call last):
  File "/opt/airflow/providers/git/src/airflow/providers/git/bundles/git.py", line 92, in __init__
    self.hook = GitHook(git_conn_id=git_conn_id or "git_default", repo_url=self.repo_url)
  File "/opt/airflow/providers/git/src/airflow/providers/git/hooks/git.py", line 69, in __init__
    connection = self.get_connection(git_conn_id)
  File "/opt/airflow/task-sdk/src/airflow/sdk/bases/hook.py", line 61, in get_connection
    conn = Connection.get(conn_id)
  File "/opt/airflow/task-sdk/src/airflow/sdk/definitions/connection.py", line 224, in get
    return _get_connection(conn_id)
  File "/opt/airflow/task-sdk/src/airflow/sdk/execution_time/context.py", line 176, in _get_connection
    raise AirflowNotFoundException(f"The conn_id `{conn_id}` isn't defined")
airflow.sdk.exceptions.AirflowNotFoundException: The conn_id `non_existent_connection` isn't defined
2025-12-05T08:45:12.175495Z [error    ] Error creating bundle 'test-git-bundle': The conn_id `non_existent_connection` isn't defined [airflow.dag_processing.bundles.manager.DagBundlesManager] loc=manager.py:249
Traceback (most recent call last):
  File "/opt/airflow/airflow-core/src/airflow/dag_processing/bundles/manager.py", line 247, in sync_bundles_to_db
    new_template, new_params = _extract_and_sign_template(name)
  File "/opt/airflow/airflow-core/src/airflow/dag_processing/bundles/manager.py", line 216, in _extract_and_sign_template
    bundle_instance = self.get_bundle(name)
  File "/opt/airflow/airflow-core/src/airflow/dag_processing/bundles/manager.py", line 337, in get_bundle
    return cfg_bundle.bundle_class(name=name, version=version, **cfg_bundle.kwargs)
  File "/opt/airflow/providers/git/src/airflow/providers/git/bundles/git.py", line 92, in __init__
    self.hook = GitHook(git_conn_id=git_conn_id or "git_default", repo_url=self.repo_url)
  File "/opt/airflow/providers/git/src/airflow/providers/git/hooks/git.py", line 69, in __init__
    connection = self.get_connection(git_conn_id)
  File "/opt/airflow/task-sdk/src/airflow/sdk/bases/hook.py", line 61, in get_connection
    conn = Connection.get(conn_id)
  File "/opt/airflow/task-sdk/src/airflow/sdk/definitions/connection.py", line 224, in get
    return _get_connection(conn_id)
  File "/opt/airflow/task-sdk/src/airflow/sdk/execution_time/context.py", line 176, in _get_connection
    raise AirflowNotFoundException(f"The conn_id `{conn_id}` isn't defined")
airflow.sdk.exceptions.AirflowNotFoundException: The conn_id `non_existent_connection` isn't defined
2025-12-05T08:45:12.175815Z [warning  ] Removing ownership of team 'None' from Dag bundle 'local-bundle' [airflow.dag_processing.bundles.manager.DagBundlesManager] loc=manager.py:28

---

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[amoghrajesh]

Sorry for the spam folks, possibly due to a bad rebase I had!

[amoghrajesh]

Ahhh missed the v3 label!

[amoghrajesh]

Oh this one will need manual port over.

[amoghrajesh]

Manual port to v3 branch here: #59236