This document records occurrences of the "Invalid Tar" bug across Retrorecon and how each was resolved.

Date	Commit	Issue	Fix
2025-06-18	93c7603	Unhandled tarfile.TarError when parsing layer blobs	Added try/except in dag.py and oci.py returning HTTP 415 with an error page
2025-06-18	870aa71	Lack of diagnostics around tar failures	Logged warnings like invalid tar for <repo>@<digest> and updated tests
2025-06-18	0ace021	Regression where layer view still crashed on bad tars	Merged fix ensuring warnings were logged and responses used 415
2025-06-18	8462a7c	Incorrect layers link used manifest digest leading to wrong blob	Adjusted filters and overlay view to compute correct digest
2025-06-18	24d3669	Manifest view built layers link with wrong digest	Fixed filter so link includes manifest digest; added tests
2025-06-18	6ee4afe	Registry overlay links pointed at stale digests	Updated JavaScript and tests to avoid invalid tar downloads
2025-06-20	19370d4	Layers route for digest images generated wrong repo path	Parsed image reference properly before calling fs_view
2025-06-20	4bcce22	/image page size links triggered invalid tar via /size	Stopped linking size column and warned on unsupported media

All OCI routes must gracefully handle invalid or truncated tar archives. When a tarfile.TarError is raised while inspecting a layer:

• Respond with HTTP 415 and render oci_error.html with message "invalid tar".
• Log a warning "invalid tar for <repo>@<digest>" (or "invalid tar blob for <image> at <digest>" for Dag Explorer).

The Dag Explorer /dag/fs endpoint should return JSON { "error": "invalid_blob" } in this case.

1. Requesting /fs/<repo>@<digest>/<path> with an invalid blob returns status 415 and logs the warning.
2. Requesting /size/<repo>@<digest> with an invalid blob returns status 415 and logs the warning.
3. Requesting /dag/fs/<digest>/<file> with an invalid blob returns JSON error and logs invalid tar blob.

These tests live in tests/test_oci_routes.py and tests/test_dag_explorer.py.