make github import-app mgmt command an atomic transaction (#18)

CHANGELOG.md

@@ -18,6 +18,10 @@ and this project attempts to adhere to [Semantic Versioning](https://semver.org/
 
 ## [Unreleased]
 
+### Fixed
+
+- `github import-app` management command is now wrapped in an atomic transaction, in case any import steps fail.
+
 ## [0.2.0]
 
 ### Added

src/django_github_app/management/commands/github.py

@@ -3,6 +3,7 @@
 from typing import Annotated
 from typing import Any
 
+from django.db import transaction
 from django_typer.management import Typer
 from typer import Option
 
@@ -34,7 +35,8 @@ def import_app(
     """
     Import an existing GitHub App to database Models.
     """
-    installation = Installation.objects.create(installation_id=installation_id)
-    installation.refresh_from_gh(account_type=type, account_name=name)
-    repository_data = installation.get_repos()
-    Repository.objects.create_from_gh_data(repository_data, installation)
+    with transaction.atomic():
+        installation = Installation.objects.create(installation_id=installation_id)
+        installation.refresh_from_gh(account_type=type, account_name=name)
+        repository_data = installation.get_repos()
+        Repository.objects.create_from_gh_data(repository_data, installation)

tests/integration/test_management_commands.py

@@ -80,3 +80,23 @@ def test_import_app_management_command(settings):
         len(installation.get_repos())
         == Repository.objects.filter(installation=installation).count()
     )
+
+
+def test_import_app_transaction(settings, monkeypatch):
+    def mock_create_from_gh_data(*args, **kwargs):
+        raise ValueError
+
+    monkeypatch.setattr(
+        Repository.objects, "create_from_gh_data", mock_create_from_gh_data
+    )
+
+    with pytest.raises(ValueError):
+        import_app(
+            type=settings.account_type,
+            name=settings.account_name,
+            installation_id=int(settings.installation_id),
+        )
+
+    assert not Installation.objects.filter(
+        installation_id=settings.installation_id
+    ).exists()