Salvage of #79604 (webtecnica) + #85721 (pierrenode), combined and
rebased onto current main with simplify-code findings folded in.
#79604: update_session_model() wrote the model name to sessions.model
but never persisted the provider into model_config. On resume, the
runtime recombined the persisted model with the config.yaml primary
provider (which may not serve that model), producing auth errors.
Fix: add optional provider parameter to update_session_model, merged
into model_config via the shared _merge_model_config_json helper (not
hand-rolled SQL). Wire both gateway /model call sites to pass
result.target_provider.
#85721: session_gateway_runtime() had no billing_provider fallback.
A CLI session that never ran /model has no gateway_runtime or
top-level provider in model_config — billing_provider (written on
every session's first accounted API call) is the only durable record.
Fix: add billing_provider as the last-resort fallback in
session_gateway_runtime(), filtering bare billing buckets (auto/custom)
that are not routable identities.
Simplify-code findings addressed:
- Use _merge_model_config_json instead of 40 lines of branched SQL
- Share _BARE_BILLING_PROVIDERS from hermes_state.py (was duplicated
as a set in tui_gateway/server.py)
- Merge None-filtering from #85920 with the billing_provider fallback
into one coherent return path
Co-authored-by: pierrenode <298902573+pierrenode@users.noreply.github.com>
The route dict in _persist_model_switch_to_session used filtering
(omits falsy values) while the top-level keys used (writes
explicit None to trigger deletion in _merge_model_config_json). This
asymmetry meant stale keys from a previous /model switch survived in
the nested gateway_runtime dict even after the fix in #85261 that
properly deleted them from the top-level keys.
Fix: build the route dict with and derive the top-level keys
from **route so both shapes always use identical deletion semantics.
Also filter None values in session_gateway_runtime's reader since
gateway_runtime is replaced as a whole dict (not deep-merged), so None
values written by the persist path survive in the nested dict.
Found by /simplify-code 3-reviewer review on #85261 (all 3 reviewers
converged on the route dict asymmetry as the verdict-relevant finding).
patch_session_model_config merges key-level and only deletes on explicit
None. Dropping falsy values from the top-level patch let a previous
switch's api_mode/base_url survive the next switch — TUI/desktop resume
then restored e.g. openrouter with anthropic_messages wire mode, and a
failed bare-custom heal produced a stale-provider/new-endpoint route.
Write absent top-level values as explicit None so each switch fully
replaces the persisted route. Regression test against a real SessionDB;
mutation-checked. Also correct the heal comment (CLI is deliberately
stricter than the TUI recovery, which keeps bare custom with a base_url).
- Bare 'custom' from ModelSwitchResult.target_provider is the resolved
billing class, not a routable identity; persisting it verbatim made a
later --resume hard-fail once the config default moved off the custom
endpoint. Heal to custom:<name> via canonical_custom_identity at
persist time, and again on restore for rows written by older builds
(mirrors tui_gateway's _stored_session_runtime_overrides recovery).
- --global switches now also update the session row: the row records
what THIS session runs, otherwise resume restored the stale
creation-time model over the user's new global choice.
- Only adopt resolved credential_pool alongside its api_key (don't null
the ambient pool when resolution returns no credentials).
- 3 new tests; healing path mutation-checked.
- Extract the two duplicated /model session-persist blocks into
_persist_model_switch_to_session; persist the route BOTH nested
(gateway_runtime, CLI reader) and top-level (TUI gateway's
_stored_session_runtime_overrides reader) so a CLI switch also
survives a desktop/TUI session.resume.
- Add SessionDB.session_gateway_runtime as the canonical tolerant
row-level route reader (session_yolo_enabled precedent); use it in
_restore_session_model instead of hand-rolled JSON parsing.
- Clear stale launch-time _explicit_api_key/_explicit_base_url when
resume restores a different provider (same leak guard
_apply_model_switch_result already has).
- 12 new tests incl. a real-SessionDB round trip; mutation-checked.
webtecnica