idpyoidc advertised PKCE support but did not actually verify the code
challenge at the token endpoint, so a sent code_challenge provided no
protection. Enable the PKCE add-on restricted to S256.
Configured as non-essential: relying parties that do not send a
code_challenge continue to work (no breaking change), but any RP that uses
PKCE must use S256, and the code_verifier is verified at token exchange.
Flip essential=True (or per-client pkce_essential) to require PKCE once all
clients have migrated.
Refs: porchlight-s48
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
- Use Annotated[str, Form()] for FastAPI dependencies (FAST002)
- Add missing type annotations across src/ and tests/ (ANN001/003/201/202)
- Reduce function arguments via request.form() reads (PLR0913)
- Combine return paths to reduce return statements (PLR0911)
- Use anyio.Path for async-safe filesystem operations (ASYNC240)
- Extract constants, helpers, and dict comprehensions for clarity
- Move inline imports to top-level (PLC0415)
- Use raw strings for regex match patterns (RUF043)
- Fix redundant get_session_user call in delete_user (not-iterable)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
