Add kubernetes Ingress backend

Signed-off-by: Emile Vauge <emile@vauge.com>

provider/k8s/ingress.go

@@ -0,0 +1,151 @@
+package k8s
+
+// Ingress is a collection of rules that allow inbound connections to reach the
+// endpoints defined by a backend. An Ingress can be configured to give services
+// externally-reachable urls, load balance traffic, terminate SSL, offer name
+// based virtual hosting etc.
+type Ingress struct {
+	TypeMeta `json:",inline"`
+	// Standard object's metadata.
+	// More info: http://releases.k8s.io/HEAD/docs/devel/api-conventions.md#metadata
+	ObjectMeta `json:"metadata,omitempty"`
+
+	// Spec is the desired state of the Ingress.
+	// More info: http://releases.k8s.io/HEAD/docs/devel/api-conventions.md#spec-and-status
+	Spec IngressSpec `json:"spec,omitempty"`
+
+	// Status is the current state of the Ingress.
+	// More info: http://releases.k8s.io/HEAD/docs/devel/api-conventions.md#spec-and-status
+	Status IngressStatus `json:"status,omitempty"`
+}
+
+// IngressList is a collection of Ingress.
+type IngressList struct {
+	TypeMeta `json:",inline"`
+	// Standard object's metadata.
+	// More info: http://releases.k8s.io/HEAD/docs/devel/api-conventions.md#metadata
+	ListMeta `json:"metadata,omitempty"`
+
+	// Items is the list of Ingress.
+	Items []Ingress `json:"items"`
+}
+
+// IngressSpec describes the Ingress the user wishes to exist.
+type IngressSpec struct {
+	// A default backend capable of servicing requests that don't match any
+	// rule. At least one of 'backend' or 'rules' must be specified. This field
+	// is optional to allow the loadbalancer controller or defaulting logic to
+	// specify a global default.
+	Backend *IngressBackend `json:"backend,omitempty"`
+
+	// TLS configuration. Currently the Ingress only supports a single TLS
+	// port, 443. If multiple members of this list specify different hosts, they
+	// will be multiplexed on the same port according to the hostname specified
+	// through the SNI TLS extension, if the ingress controller fulfilling the
+	// ingress supports SNI.
+	TLS []IngressTLS `json:"tls,omitempty"`
+
+	// A list of host rules used to configure the Ingress. If unspecified, or
+	// no rule matches, all traffic is sent to the default backend.
+	Rules []IngressRule `json:"rules,omitempty"`
+	// TODO: Add the ability to specify load-balancer IP through claims
+}
+
+// IngressTLS describes the transport layer security associated with an Ingress.
+type IngressTLS struct {
+	// Hosts are a list of hosts included in the TLS certificate. The values in
+	// this list must match the name/s used in the tlsSecret. Defaults to the
+	// wildcard host setting for the loadbalancer controller fulfilling this
+	// Ingress, if left unspecified.
+	Hosts []string `json:"hosts,omitempty"`
+	// SecretName is the name of the secret used to terminate SSL traffic on 443.
+	// Field is left optional to allow SSL routing based on SNI hostname alone.
+	// If the SNI host in a listener conflicts with the "Host" header field used
+	// by an IngressRule, the SNI host is used for termination and value of the
+	// Host header is used for routing.
+	SecretName string `json:"secretName,omitempty"`
+	// TODO: Consider specifying different modes of termination, protocols etc.
+}
+
+// IngressStatus describe the current state of the Ingress.
+type IngressStatus struct {
+	// LoadBalancer contains the current status of the load-balancer.
+	LoadBalancer LoadBalancerStatus `json:"loadBalancer,omitempty"`
+}
+
+// IngressRule represents the rules mapping the paths under a specified host to
+// the related backend services. Incoming requests are first evaluated for a host
+// match, then routed to the backend associated with the matching IngressRuleValue.
+type IngressRule struct {
+	// Host is the fully qualified domain name of a network host, as defined
+	// by RFC 3986. Note the following deviations from the "host" part of the
+	// URI as defined in the RFC:
+	// 1. IPs are not allowed. Currently an IngressRuleValue can only apply to the
+	//	  IP in the Spec of the parent Ingress.
+	// 2. The `:` delimiter is not respected because ports are not allowed.
+	//	  Currently the port of an Ingress is implicitly :80 for http and
+	//	  :443 for https.
+	// Both these may change in the future.
+	// Incoming requests are matched against the host before the IngressRuleValue.
+	// If the host is unspecified, the Ingress routes all traffic based on the
+	// specified IngressRuleValue.
+	Host string `json:"host,omitempty"`
+	// IngressRuleValue represents a rule to route requests for this IngressRule.
+	// If unspecified, the rule defaults to a http catch-all. Whether that sends
+	// just traffic matching the host to the default backend or all traffic to the
+	// default backend, is left to the controller fulfilling the Ingress. Http is
+	// currently the only supported IngressRuleValue.
+	IngressRuleValue `json:",inline,omitempty"`
+}
+
+// IngressRuleValue represents a rule to apply against incoming requests. If the
+// rule is satisfied, the request is routed to the specified backend. Currently
+// mixing different types of rules in a single Ingress is disallowed, so exactly
+// one of the following must be set.
+type IngressRuleValue struct {
+	//TODO:
+	// 1. Consider renaming this resource and the associated rules so they
+	// aren't tied to Ingress. They can be used to route intra-cluster traffic.
+	// 2. Consider adding fields for ingress-type specific global options
+	// usable by a loadbalancer, like http keep-alive.
+
+	HTTP *HTTPIngressRuleValue `json:"http,omitempty"`
+}
+
+// HTTPIngressRuleValue is a list of http selectors pointing to backends.
+// In the example: http://<host>/<path>?<searchpart> -> backend where
+// where parts of the url correspond to RFC 3986, this resource will be used
+// to match against everything after the last '/' and before the first '?'
+// or '#'.
+type HTTPIngressRuleValue struct {
+	// A collection of paths that map requests to backends.
+	Paths []HTTPIngressPath `json:"paths"`
+	// TODO: Consider adding fields for ingress-type specific global
+	// options usable by a loadbalancer, like http keep-alive.
+}
+
+// HTTPIngressPath associates a path regex with a backend. Incoming urls matching
+// the path are forwarded to the backend.
+type HTTPIngressPath struct {
+	// Path is a extended POSIX regex as defined by IEEE Std 1003.1,
+	// (i.e this follows the egrep/unix syntax, not the perl syntax)
+	// matched against the path of an incoming request. Currently it can
+	// contain characters disallowed from the conventional "path"
+	// part of a URL as defined by RFC 3986. Paths must begin with
+	// a '/'. If unspecified, the path defaults to a catch all sending
+	// traffic to the backend.
+	Path string `json:"path,omitempty"`
+
+	// Backend defines the referenced service endpoint to which the traffic
+	// will be forwarded to.
+	Backend IngressBackend `json:"backend"`
+}
+
+// IngressBackend describes all endpoints for a given service and port.
+type IngressBackend struct {
+	// Specifies the name of the referenced service.
+	ServiceName string `json:"serviceName"`
+
+	// Specifies the port of the referenced service.
+	ServicePort IntOrString `json:"servicePort"`
+}