Files
k3k/pkg/controller/cluster/server/config.go
T
2026-06-16 12:16:48 +02:00

115 lines
3.7 KiB
Go

package server
import (
"fmt"
"gopkg.in/yaml.v3"
"k8s.io/apimachinery/pkg/util/sets"
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"github.com/rancher/k3k/pkg/apis/k3k.io/v1beta1"
"github.com/rancher/k3k/pkg/controller"
)
// serverConfig are few options from k3s server options that will
// construct the yaml config file for k3s server
type serverConfig struct {
ClusterCIDR string `yaml:"cluster-cidr,omitempty"`
ClusterDNS string `yaml:"cluster-dns,omitempty"`
ClusterInit bool `yaml:"cluster-init,omitempty"`
DisableAgent bool `yaml:"disable-agent,omitempty"`
Disable []string `yaml:"disable,omitempty"`
EgressSelectorMode string `yaml:"egress-selector-mode,omitempty"`
KubeApiServerArg []string `yaml:"kube-apiserver-arg,omitempty"`
Server string `yaml:"server,omitempty"`
ServiceCIDR string `yaml:"service-cidr,omitempty"`
TLSSAN []string `yaml:"tls-san,omitempty"`
Token string `yaml:"token,omitempty"`
}
func (s *Server) Config(init bool, serviceIP string) (*corev1.Secret, error) {
name := configSecretName(s.cluster.Name, init)
serverConfig := buildServerConfig(s.cluster, init, serviceIP, s.token)
config, err := yaml.Marshal(serverConfig)
if err != nil {
return nil, err
}
return &corev1.Secret{
TypeMeta: metav1.TypeMeta{
Kind: "Secret",
APIVersion: "v1",
},
ObjectMeta: metav1.ObjectMeta{
Name: name,
Namespace: s.cluster.Namespace,
},
Data: map[string][]byte{
"config.yaml": config,
},
}, nil
}
func buildServerConfig(cluster *v1beta1.Cluster, initServer bool, serviceIP, token string) serverConfig {
sans := sets.NewString(cluster.Spec.TLSSANs...)
sans.Insert(
serviceIP,
ServiceName(cluster.Name),
fmt.Sprintf("%s.%s", ServiceName(cluster.Name), cluster.Namespace),
)
cluster.Status.TLSSANs = sans.List()
serverConfig := serverConfig{
ClusterInit: true,
Token: token,
TLSSAN: cluster.Status.TLSSANs,
ServiceCIDR: cluster.Status.ServiceCIDR,
ClusterCIDR: cluster.Status.ClusterCIDR,
ClusterDNS: cluster.Spec.ClusterDNS,
}
if !initServer {
serverConfig.Server = "https://" + serviceIP
}
// shared and hcp modes both run K3s with --disable-agent (agentless server).
switch cluster.Spec.Mode {
case "", v1beta1.SharedClusterMode:
serverConfig.DisableAgent = true
serverConfig.EgressSelectorMode = "disabled"
serverConfig.Disable = []string{"servicelb", "traefik", "metrics-server", "local-storage"}
case v1beta1.HCPClusterMode:
serverConfig.DisableAgent = true
// Tunnel apiserver egress through the k3s-agent WebSocket: the
// apiserver has no route to the virtual cluster's pod CIDR and
// bypasses kube-proxy when dialing pod IPs (webhooks, log/exec).
// "cluster" is the only safe mode — "agent" lets pod dials go
// direct (no route, fails); "pod" only permits pod IPs the agent
// has already watched, so a newly-created pod's IP is rejected
// and tears down the remotedialer session, making kubelet streams
// flaky. See k3s pkg/agent/tunnel/tunnel.go.
serverConfig.EgressSelectorMode = "cluster"
// Disable the apiserver's built-in endpoint reconciler so K3k can
// own default/kubernetes Endpoints and point it at the externally
// reachable host:port (NodePort / LB / Ingress).
serverConfig.KubeApiServerArg = append(serverConfig.KubeApiServerArg, "endpoint-reconciler-type=none")
case v1beta1.VirtualClusterMode:
// no extra config for virtual mode
}
return serverConfig
}
func configSecretName(clusterName string, init bool) string {
if !init {
return controller.SafeConcatNameWithPrefix(clusterName, configName)
}
return controller.SafeConcatNameWithPrefix(clusterName, initConfigName)
}