gateway api 1.0.0 standard

Gateway represents an instance of a service-traffic handling infrastructure by binding Listeners to a set of IP addresses.

GatewayClass describes a class of Gateways available to the user for creating Gateway resources. It is recommended that this resource be used as a template for Gateways. This means that a Gateway is based on the state of the GatewayClass at the time it was created and changes to the GatewayClass or associated parameters are not propagated down to existing Gateways. This recommendation is intended to limit the blast radius of changes to GatewayClass or associated parameters. If implementations choose to propagate GatewayClass changes to existing Gateways, that MUST be clearly documented by the implementation. Whenever one or more Gateways are using a GatewayClass, implementations SHOULD add the `gateway-exists-finalizer.gateway.networking.k8s.io` finalizer on the associated GatewayClass. This ensures that a GatewayClass associated with a Gateway is not deleted while in use. GatewayClass is a Cluster level resource.

HTTPRoute provides a way to route HTTP requests. This includes the capability to match requests by hostname, path, header, or query param. Filters can be used to specify additional processing steps. Backends specify where matching requests should be routed.

ReferenceGrant identifies kinds of resources in other namespaces that are trusted to reference the specified kinds of resources in the same namespace as the policy. Each ReferenceGrant can be used to represent a unique trust relationship. Additional Reference Grants can be used to add to the set of trusted sources of inbound references for the namespace they are defined within. A ReferenceGrant is required for all cross-namespace references in Gateway API (with the exception of cross-namespace Route-Gateway attachment, which is governed by the AllowedRoutes configuration on the Gateway, and cross-namespace Service ParentRefs on a "consumer" mesh Route, which defines routing rules applicable only to workloads in the Route namespace). ReferenceGrants allowing a reference from a Route to a Service are only applicable to BackendRefs. ReferenceGrant is a form of runtime verification allowing users to assert which cross-namespace object references are permitted. Implementations that support ReferenceGrant MUST NOT permit cross-namespace references which have no grant, and MUST respond to the removal of a grant by revoking the access that the grant allowed.