controller

Documentation

Overview

Package controller orchestrates Ingress and Gateway-API informers, extracting hostnames into a sorted, deduplicated set that downstream reconcilers (CoreDNS, /etc/hosts) write into the cluster.

Index

• func ExtractHostnames(ingresses []*networkingv1.Ingress, gateways []*gatewayv1.Gateway, ...) []string
• func FilterGateways(gateways []*gatewayv1.Gateway, className string) []*gatewayv1.Gateway
• func FilterHTTPRoutes(routes []*gatewayv1.HTTPRoute, survivors []*gatewayv1.Gateway) []*gatewayv1.HTTPRoute
• func FilterIngresses(ingresses []*networkingv1.Ingress, className string) []*networkingv1.Ingress
• type Controller
  • func New(opts *Options) *Controller
  • func (c *Controller) Run(ctx context.Context) error
• type Options
• type ReconcileFunc

Functions

func ExtractHostnames

func ExtractHostnames(
	ingresses []*networkingv1.Ingress,
	gateways []*gatewayv1.Gateway,
	routes []*gatewayv1.HTTPRoute,
) []string

ExtractHostnames flattens hostnames from the given Ingresses, Gateways, and HTTPRoutes into a single lowercased, deduplicated, sorted slice. Wildcard patterns ("*.example.com") and empty strings are dropped because CoreDNS "rewrite name" (and /etc/hosts) cannot express them. Nil entries are tolerated.

func FilterGateways

func FilterGateways(gateways []*gatewayv1.Gateway, className string) []*gatewayv1.Gateway

FilterGateways returns only Gateways whose spec.gatewayClassName matches className. Empty className disables the filter (all non-nil Gateways pass through). Unlike Ingress, Gateway requires gatewayClassName as a non-optional field — there is no "ambiguous Gateway" case to drop.

func FilterHTTPRoutes

func FilterHTTPRoutes(routes []*gatewayv1.HTTPRoute, survivors []*gatewayv1.Gateway) []*gatewayv1.HTTPRoute

FilterHTTPRoutes returns only HTTPRoutes attached (via parentRefs) to one of the supplied surviving Gateways. A nil survivors slice disables the filter (every non-nil route passes through). HTTPRoutes have no class of their own — they inherit it through the Gateway they target, so the filter follows the parentRefs.

ParentRef.Namespace is optional; the Gateway-API spec defaults it to the route's own namespace, and the filter applies that default before matching. A multi-parent route is kept whenever AT LEAST ONE parentRef points at a surviving Gateway: the hostname still reaches the proxy that way, so hairpin is still required.

func FilterIngresses

func FilterIngresses(ingresses []*networkingv1.Ingress, className string) []*networkingv1.Ingress

FilterIngresses returns only Ingresses whose spec.ingressClassName matches className. An empty className disables the filter — every non-nil Ingress passes through, preserving the v0.1/v0.2 behaviour for clusters with a single ingress-controller.

When a filter IS set, Ingresses without an explicit ingressClassName are dropped: they are ambiguous, and silently hairpinning them via the wrong ingress-controller is exactly the failure mode operators with multiple controllers want this filter to prevent (upstream issue #17).

Types

type Controller

type Controller struct {
	// contains filtered or unexported fields
}

Controller watches Ingress resources (and optionally Gateway+HTTPRoute) and fans every event into a single rate-limited workqueue key so reconcile calls coalesce naturally.

func New

func New(opts *Options) *Controller

New builds a Controller. Logger == nil silences output. The supplied Options pointer is NOT mutated — defaulting happens on the local copy so callers can safely reuse the struct (e.g. in tests). A nil opts pointer is treated as an empty Options{} rather than panicking — keeps callers safe during early bootstrap where Options may be assembled piece-meal.

func (*Controller) Run

func (c *Controller) Run(ctx context.Context) error

Run starts informers and the reconcile worker. It blocks until ctx is canceled or a fatal error occurs. Returns nil on clean shutdown.

type Options

type Options struct {
	Core         kubernetes.Interface
	Gateway      gatewayclient.Interface
	EnableGW     bool
	Reconciler   ReconcileFunc
	ResyncPeriod time.Duration
	Logger       *slog.Logger

	// IngressClass, when non-empty, restricts hostname extraction to
	// Ingresses whose spec.ingressClassName matches it. Ingresses without an
	// explicit class are dropped under the filter — see FilterIngresses for
	// the rationale (hairpin-proxy upstream issue #17: multiple
	// ingress-controllers with different PROXY-protocol settings).
	IngressClass string

	// GatewayClass, when non-empty, restricts hostname extraction to
	// Gateways whose spec.gatewayClassName matches it, and to HTTPRoutes
	// attached (via parentRefs) to one of the surviving Gateways.
	GatewayClass string
}

Options bundles Controller dependencies.

type ReconcileFunc

type ReconcileFunc func(ctx context.Context, hosts []string) error

ReconcileFunc applies a desired hostname set somewhere (CoreDNS ConfigMap, /etc/hosts file, etc.). It is called from a single worker goroutine, so the implementation does not need to be reentrant.