hodl

[NicoHinderling]

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[NicoHinderling]

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• hodl #109397 👈 (View in Graphite)
• feat(preprod): Add snapshot image comparison task and endpoint logic #109151 : 2 other dependent PRs (#109403 , #109546 )
• feat(preprod): Add snapshot comparison task #109382
• feat(preprod): Add image comparison library with odiff batch support #109381
• feat(preprod): Add odiff server wrapper and Dockerfile binary install #109380
• master

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[github-actions]

🚨 Warning: This pull request contains Frontend and Backend changes!

It's discouraged to make changes to Sentry's Frontend and Backend in a single pull request. The Frontend and Backend are not atomically deployed. If the changes are interdependent of each other, they must be separated into two pull requests and be made forward or backwards compatible, such that the Backend or Frontend can be safely deployed independently.

Have questions? Please ask in the #discuss-dev-infra channel.

[sentry-warden]

Unhandled ValueError when snapshot_id is non-numeric string

The endpoint accepts snapshot_id as a URL parameter (matched by [^/]+ pattern allowing any string) and passes it directly to .get(id=snapshot_id). When snapshot_id is a non-integer string like 'abc', Django raises ValueError: invalid literal for int() with base 10. Only DoesNotExist is caught, so the ValueError propagates as an unhandled 500 error. Other preprod endpoints like PreprodArtifactEndpoint explicitly catch both DoesNotExist and ValueError.

Verification

Verified by reading: 1) The URL pattern in urls.py line 84 uses [^/]+ which accepts any string for snapshot_id. 2) The PreprodArtifactEndpoint base class (preprod_artifact_endpoint.py lines 55-60) properly catches both exceptions. 3) The PreprodArtifactAdminRerunAnalysisEndpoint (lines 147-153) explicitly validates the ID is numeric. 4) Django ORM raises ValueError when a non-integer string is used for an integer PK lookup.

Suggested fix: Catch ValueError in addition to DoesNotExist and return a 404 response

Suggested change

	try:
	artifact = PreprodArtifact.objects.select_related("commit_comparison").get(
	id=snapshot_id, project_id=project.id
	)
	id=int(snapshot_id), project_id=project.id
	except (PreprodArtifact.DoesNotExist, ValueError):

Also found at 1 additional location

• src/sentry/preprod/api/endpoints/snapshot_diff.py:28-28

Identified by Warden sentry-backend-bugs · 54R-HMN

[sentry-warden]

AttributeError when compare_images returns None

The compare_images() function can return None when image processing fails (see _compare_pairs exception handling in compare.py lines 81-83). On lines 43-54, the code accesses result.diff_mask_png, result.diff_score, etc. without checking if result is None, causing AttributeError: 'NoneType' object has no attribute 'diff_mask_png'. This matches the SENTRY-3Z3P pattern where serializers return None instead of a dict.

Verification

Read compare.py and confirmed compare_images() has return type DiffResult | None. The _compare_pairs function catches exceptions and appends None to results (lines 81-83). The endpoint accesses result attributes without a None check.

Suggested fix: Add a None check after calling compare_images and return an appropriate error response.

Suggested change

	{
	"diff_mask_png": result.diff_mask_png,
	"diff_score": result.diff_score,
	"changed_pixels": result.changed_pixels,
	"total_pixels": result.total_pixels,
	"aligned_height": result.aligned_height,
	"width": result.width,
	"before_width": result.before_width,
	"before_height": result.before_height,
	"after_width": result.after_width,
	"after_height": result.after_height,
	}
	if result is None:
	return Response({"detail": "Failed to compare images"}, status=400)

Identified by Warden sentry-backend-bugs · 2S4-7SS