Tidy DagVersion/DagCode metadata helpers

[ephraimbuddy]

• get_version: use 'if version_number is not None' so version_number=0 filters (and 404s) instead of falling through to the latest version.
• bundle_url: drop the dead hasattr(self.bundle, 'signed_url_template') guard (always true on the ORM model). Behavior is unchanged: a loaded bundle uses render_url(), and the deprecated manager lookup is used only when there is no bundle row -- not on every call for bundles without a URL template.
• DagCode.update_source_code: refresh fileloc alongside the source, and drop the redundant session.merge() on the already-session-attached row.

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claude opus 4.8

[Copilot]

Pull request overview

This PR tidies up Airflow’s DAG version/code metadata helpers by fixing edge-case filtering behavior, simplifying bundle URL resolution logic, and ensuring DagCode.update_source_code() keeps related metadata consistent.

Changes:

• Fix DagVersion.get_version() so version_number=0 is treated as a real filter (instead of falling back to “latest”).
• Simplify DagVersion.bundle_url by relying on DagBundleModel.render_url() when a bundle row is present and only using the deprecated manager path when no bundle row exists.
• Update DagCode.update_source_code() to refresh fileloc when the source is refreshed, and add regression coverage.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
airflow-core/src/airflow/models/dag_version.py	Fixes get_version zero-filter behavior; refines bundle_url selection logic.
airflow-core/src/airflow/models/dagcode.py	Updates update_source_code to keep fileloc aligned when refreshing stored source.
airflow-core/tests/unit/models/test_dag_version.py	Adds regression test ensuring version_number=0 filters rather than returning latest.
airflow-core/tests/unit/models/test_dagcode.py	Adds regression test verifying update_source_code refreshes stale fileloc on update path.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

[phanikumv]

CI is red on all four core DB jobs because of the bundle_url guard removal, a
test that was dependent on this logic needs fixing

Suggested replacement for airflow-core/tests/unit/api_fastapi/core_api/routes/public/test_dag_versions.py here

@pytest.mark.usefixtures("make_dag_with_multiple_versions")
@mock.patch("airflow.models.dagbundle.DagBundleModel.render_url", return_value=None)
def test_get_dag_version_with_unconfigured_bundle(self, mock_render_url, test_client):
    """A bundle row with no URL template yields an empty bundle_url."""
    response = test_client.get("/dags/dag_with_multiple_versions/dagVersions/1")
    assert response.status_code == 200
    assert not response.json()["bundle_url"]

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

[phanikumv]

The PR tests the internal function get_version(), users never call it directly . Worth adding a test that calls the actual API endpoint GET /dagSources/{dag_id}?version_number=0, and asserts that it gets a 404