diff --git a/staging/src/k8s.io/api/discovery/v1/types.go b/staging/src/k8s.io/api/discovery/v1/types.go index d6a9d0fcedb..9ddcda269c4 100644 --- a/staging/src/k8s.io/api/discovery/v1/types.go +++ b/staging/src/k8s.io/api/discovery/v1/types.go @@ -25,9 +25,12 @@ import ( // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object // +k8s:prerelease-lifecycle-gen:introduced=1.21 -// EndpointSlice represents a subset of the endpoints that implement a service. -// For a given service there may be multiple EndpointSlice objects, selected by -// labels, which must be joined to produce the full set of endpoints. +// EndpointSlice represents a set of service endpoints. Most EndpointSlices are created by +// the EndpointSlice controller to represent the Pods selected by Service objects. For a +// given service there may be multiple EndpointSlice objects which must be joined to +// produce the full set of endpoints; you can find all of the slices for a given service +// by listing EndpointSlices in the service's namespace whose `kubernetes.io/service-name` +// label contains the service's name. type EndpointSlice struct { metav1.TypeMeta `json:",inline"` @@ -41,7 +44,10 @@ type EndpointSlice struct { // supported: // * IPv4: Represents an IPv4 Address. // * IPv6: Represents an IPv6 Address. - // * FQDN: Represents a Fully Qualified Domain Name. + // * FQDN: Represents a Fully Qualified Domain Name. (Deprecated) + // The EndpointSlice controller only generates, and kube-proxy only processes, + // slices of addressType "IPv4" and "IPv6". No semantics are defined for + // the "FQDN" type. AddressType AddressType `json:"addressType" protobuf:"bytes,4,rep,name=addressType"` // endpoints is a list of unique endpoints in this slice. Each slice may @@ -50,10 +56,11 @@ type EndpointSlice struct { Endpoints []Endpoint `json:"endpoints" protobuf:"bytes,2,rep,name=endpoints"` // ports specifies the list of network ports exposed by each endpoint in - // this slice. Each port must have a unique name. When ports is empty, it - // indicates that there are no defined ports. When a port is defined with a - // nil port value, it indicates "all ports". Each slice may include a + // this slice. Each port must have a unique name. Each slice may include a // maximum of 100 ports. + // Services always have at least 1 port, so EndpointSlices generated by the + // EndpointSlice controller will likewise always have at least 1 port. + // EndpointSlices used for other purposes may have an empty ports list. // +optional // +listType=atomic Ports []EndpointPort `json:"ports" protobuf:"bytes,3,rep,name=ports"` @@ -76,12 +83,12 @@ const ( // Endpoint represents a single logical "backend" implementing a service. type Endpoint struct { - // addresses of this endpoint. The contents of this field are interpreted - // according to the corresponding EndpointSlice addressType field. Consumers - // must handle different types of addresses in the context of their own - // capabilities. This must contain at least one address but no more than - // 100. These are all assumed to be fungible and clients may choose to only - // use the first element. Refer to: https://issue.k8s.io/106267 + // addresses of this endpoint. For EndpointSlices of addressType "IPv4" or "IPv6", + // the values are IP addresses in canonical form. The syntax and semantics of + // other addressType values are not defined. This must contain at least one + // address but no more than 100. EndpointSlices generated by the EndpointSlice + // controller will always have exactly 1 address. No semantics are defined for + // additional addresses beyond the first, and kube-proxy does not look at them. // +listType=set Addresses []string `json:"addresses" protobuf:"bytes,1,rep,name=addresses"` @@ -127,26 +134,25 @@ type Endpoint struct { // EndpointConditions represents the current condition of an endpoint. type EndpointConditions struct { - // ready indicates that this endpoint is prepared to receive traffic, + // ready indicates that this endpoint is ready to receive traffic, // according to whatever system is managing the endpoint. A nil value - // indicates an unknown state. In most cases consumers should interpret this - // unknown state as ready. For compatibility reasons, ready should never be - // "true" for terminating endpoints, except when the normal readiness - // behavior is being explicitly overridden, for example when the associated - // Service has set the publishNotReadyAddresses flag. + // should be interpreted as "true". In general, an endpoint should be + // marked ready if it is serving and not terminating, though this can + // be overridden in some cases, such as when the associated Service has + // set the publishNotReadyAddresses flag. // +optional Ready *bool `json:"ready,omitempty" protobuf:"bytes,1,name=ready"` - // serving is identical to ready except that it is set regardless of the - // terminating state of endpoints. This condition should be set to true for - // a ready endpoint that is terminating. If nil, consumers should defer to - // the ready condition. + // serving indicates that this endpoint is able to receive traffic, + // according to whatever system is managing the endpoint. For endpoints + // backed by pods, the EndpointSlice controller will mark the endpoint + // as serving if the pod's Ready condition is True. A nil value should be + // interpreted as "true". // +optional Serving *bool `json:"serving,omitempty" protobuf:"bytes,2,name=serving"` // terminating indicates that this endpoint is terminating. A nil value - // indicates an unknown state. Consumers should interpret this unknown state - // to mean that the endpoint is not terminating. + // should be interpreted as "false". // +optional Terminating *bool `json:"terminating,omitempty" protobuf:"bytes,3,name=terminating"` } @@ -183,8 +189,9 @@ type EndpointPort struct { Protocol *v1.Protocol `json:"protocol,omitempty" protobuf:"bytes,2,name=protocol"` // port represents the port number of the endpoint. - // If this is not specified, ports are not restricted and must be - // interpreted in the context of the specific consumer. + // If the EndpointSlice is derived from a Kubernetes service, this must be set + // to the service's target port. EndpointSlices used for other purposes may have + // a nil port. Port *int32 `json:"port,omitempty" protobuf:"bytes,3,opt,name=port"` // The application protocol for this port.