Each source (per-call kwargs, environment variables, the Python module) now
builds an HttpSettingsLayer, and HttpSettings::from_layers merges them with
explicit precedence. The aiohttp and httpx proxy-env rule is resolved once in
the merge, so HttpSettings carries a single trust_proxy_env flag
HttpClientConfig::resolve becomes From<&HttpSettings> for Resolution and client_builder becomes TryFrom<&HttpClientConfig> for reqwest::ClientBuilder, matching the rustls conversion. The verify decision moves into From<&HttpSettings> for Verify, and the proxy environment rule moves next to its flags as HttpSettings::trusts_proxy_env. The curve and cipher results are read with transpose and a default selection, which removes the tuple destructuring
KeyExchangeGroup and Tls12CipherSuite parse with FromStr and fail with Unsupported, so a setting rustls cannot honor is a typed error instead of a missing value. The cipher string conversions cannot fail and use From. The rustls ClientConfig is built with TryFrom<&HttpClientConfig>, and the built-in root store is constructed in one expression
litellm-http now builds the rustls config itself, so one route-neutral place covers roots, the client certificate, ALPN, ssl_ecdh_curve and ssl_security_level. A curve picks the single key exchange group. A cipher string restricts the TLS 1.2 suites it names, and entries rustls cannot express, such as @SECLEVEL=1, are logged once and skipped.
user_url_validation and user_url_allowed_hosts are applied by the media fetcher. Document downloads honor the environment proxy whenever provider calls do, keeping the per-hop address check, and stay on the pinned resolver when no proxy applies.
AIOHTTP_SO_KEEPALIVE, AIOHTTP_TCP_KEEPIDLE, AIOHTTP_TCP_KEEPINTVL, AIOHTTP_TCP_KEEPCNT and AIOHTTP_KEEPALIVE_TIMEOUT map onto the client. A client= argument and a live SSLContext are ignored
Python OCR passes the call timeout per request, so its connect timeout is the call timeout and never the 5s handler default. 10s is what every Rust route uses on main. The media client never uses a proxy, so trust_proxy_env no longer splits its pool key
Python's aiohttp transport reads HTTP(S)_PROXY on every request unless disable_aiohttp_trust_env is set, so the Rust clients now do the same instead of requiring aiohttp_trust_env. Transport error messages include reqwest's source chain, so a rejected certificate or refused connection is no longer reported as just 'error sending request'
Honor environment proxies whenever Python would use httpx (sync calls, HTTP/2, aiohttp disabled), apply the per-call ssl_verify argument, ignore empty or missing SSL env values the way http_handler.py does, expire pooled clients after an hour so rotated certificates reload, keep the client certificate off media downloads, and decline instead of raising when a litellm global has an unexpected type
Drop the core ocr() facade so VertexAuth and the http pool stay out of litellm-core's
public API, move the http Error enum to error.rs, and inject the media DNS resolver into
HttpClientPool instead of a per-call builder hook the cache key ignored.
The bridge now reads litellm.* HTTP settings only through litellm/rust_bridge/settings.py,
pinned by python_settings.json, while env overrides stay in Rust. This adds the Python
default User-Agent, parses string ssl_verify globals like get_ssl_verify, drops per-call
ssl_verify that Python OCR never honored, and removes the unused request_timeout.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>