Crate cc_lb_plugin_api 

Public plugin contract for the cc-lb proxy lifecycle.

The core proxy owns the wire-level server loop and drives requests through parse -> authenticate -> route -> shape -> sign -> relay_stream. This crate defines the stable types and object-safe traits used at those boundaries: authentication plugins identify a Principal, router plugins choose an Upstream and UpstreamDialect, dialects build a ShapedRequest, signers consume it into a SignedRequest, and the core relays the signed request while emitting ObserveEvent values to observability hooks.

The crate deliberately uses http, bytes, and url types instead of exposing the server’s transport implementation. Request body validation, semantic JSON checks, and concrete HTTP client behavior live in downstream crates, not in this API contract.

Re-exports

pub use types::CredentialStrategy;

pub use types::InternalError;

pub use types::InternalErrorKind;

pub use types::InternalErrorStage;

pub use types::ObserveEvent;

pub use types::PerCandidateReason;

pub use types::PluginManifest;

pub use types::Principal;

pub use types::PrincipalKind;

pub use types::PrincipalQuotas;

pub use types::RateLimitKind;

pub use types::RateLimitObservation;

pub use types::RequestContext;

pub use types::RetryDecision;

pub use types::RouteDecision;

pub use types::RoutingTrace;

pub use types::ShapedRequest;

pub use types::ShapedRequestBuilder;

pub use types::SignedRequest;

pub use types::SigningCapability;

pub use types::SubscriptionQuotaCandidateSnapshot;

pub use types::SubscriptionQuotaDataState;

pub use types::TerminalStrategy;

pub use types::Upstream;

pub use types::UpstreamCandidate;

pub use types::UpstreamKind;

pub use types::shape_request;

pub use types::sign_request;

Modules

types

Shared public data types for plugin boundaries.

Structs

FilterOutput

Filter plugin output containing upstream selection results and per-candidate reasons.

Enums

DialectError

Request shaping failures returned by crate::UpstreamDialect.

FilterError

Filter plugin errors returned by FilterPlugin.

ObservabilityError

Observability hook failures returned by crate::ObservabilityHook.

RouteError

Routing failures returned by crate::RouterPlugin.

RuntimeError

Plugin runtime failures returned by crate::PluginRuntime.

SignerError

Signing failures returned by crate::Signer and crate::SignerFactory.

UpstreamError

Upstream failures observed after a request has been relayed.

Constants

BUILTIN_CACHE_AFFINITY_ID

Stable registry id for the built-in cache-affinity router filter.

BUILTIN_CACHE_AFFINITY_NAME

Stable registry name for the built-in cache-affinity router filter.

BUILTIN_CACHE_AFFINITY_WIRE_VERSION

Wire version exposed by the built-in cache-affinity router filter.

Traits

ApiKeyAwareSignerFactory

Factory extension that binds signer construction to the router-selected upstream.

FilterPlugin

Filter plugin boundary for upstream candidate filtering and decision-making.

ObservabilityHook

Non-blocking observability hook boundary.

PluginRuntime

Runtime abstraction for concrete plugin systems such as Extism.

RouterPluginDeprecated

Router plugin boundary.

Signer

Signer boundary for applying credentials to shaped requests.

SignerFactory

Factory that builds upstream-specific signers.

UpstreamDialect

Upstream dialect boundary for request shaping and error normalization.