https://www.drmhse.com/tags/saml/Recent content in Saml on DRM HSEHugoenWed, 15 Jul 2026 22:13:24 +0300https://www.drmhse.com/posts/check-then-act-race-condition/Thu, 20 Nov 2025 05:20:09 +0000https://www.drmhse.com/posts/check-then-act-race-condition/<p>A concurrent integration test caught a failure in a SAML certificate-rotation endpoint. The API used Rust, <code>axum</code>, SeaORM, and PostgreSQL. Each request followed a reasonable sequence: find the active signing key, deactivate it, then insert its replacement.</p> <p>That sequence was only correct while one request ran at a time.</p> <p>When the test sent two rotation requests together, one of them returned <code>500 Internal Server Error</code> with a PostgreSQL <code>UniqueViolation</code>. The database had protected the data, but the handler had not treated the read and the following writes as one concurrent operation.</p>