k3s/pkg/spegel/bootstrap.go

258 lines
7.2 KiB
Go

package spegel
import (
"context"
"encoding/json"
"errors"
"os"
"path/filepath"
"strings"
"time"
"github.com/k3s-io/k3s/pkg/clientaccess"
"github.com/k3s-io/k3s/pkg/daemons/config"
"github.com/k3s-io/k3s/pkg/util"
"github.com/k3s-io/k3s/pkg/version"
"github.com/libp2p/go-libp2p/core/peer"
pkgerrors "github.com/pkg/errors"
"github.com/rancher/wrangler/v3/pkg/merr"
"github.com/sirupsen/logrus"
"github.com/spegel-org/spegel/pkg/routing"
"golang.org/x/sync/errgroup"
v1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/labels"
"k8s.io/apimachinery/pkg/util/wait"
nodeutil "k8s.io/kubernetes/pkg/controller/util/node"
)
// explicit interface checks
var _ routing.Bootstrapper = &selfBootstrapper{}
var _ routing.Bootstrapper = &agentBootstrapper{}
var _ routing.Bootstrapper = &serverBootstrapper{}
var _ routing.Bootstrapper = &chainingBootstrapper{}
type selfBootstrapper struct {
id string
}
// NewSelfBootstrapper returns a stub p2p bootstrapper that just returns its own ID
func NewSelfBootstrapper() routing.Bootstrapper {
return &selfBootstrapper{}
}
func (s *selfBootstrapper) Run(ctx context.Context, id string) error {
s.id = id
return waitForDone(ctx)
}
func (s *selfBootstrapper) Get(ctx context.Context) ([]peer.AddrInfo, error) {
if s.id == "" {
return nil, errors.New("p2p peer not ready")
}
self, err := peer.AddrInfoFromString(s.id)
if err != nil {
return nil, err
}
return []peer.AddrInfo{*self}, nil
}
type agentBootstrapper struct {
server string
token string
clientCert string
clientKey string
kubeConfig string
info *clientaccess.Info
}
// NewAgentBootstrapper returns a p2p bootstrapper that retrieves a peer address from its server
func NewAgentBootstrapper(server, token, dataDir string) routing.Bootstrapper {
return &agentBootstrapper{
clientCert: filepath.Join(dataDir, "agent", "client-kubelet.crt"),
clientKey: filepath.Join(dataDir, "agent", "client-kubelet.key"),
kubeConfig: filepath.Join(dataDir, "agent", "kubelet.kubeconfig"),
server: server,
token: token,
}
}
func (c *agentBootstrapper) Run(ctx context.Context, id string) error {
if c.server != "" && c.token != "" {
withCert := clientaccess.WithClientCertificate(c.clientCert, c.clientKey)
info, err := clientaccess.ParseAndValidateToken(c.server, c.token, withCert)
if err != nil {
return pkgerrors.WithMessage(err, "failed to validate join token")
}
c.info = info
}
client, err := util.GetClientSet(c.kubeConfig)
if err != nil {
return pkgerrors.WithMessage(err, "failed to create kubernetes client")
}
nodes := client.CoreV1().Nodes()
go wait.PollUntilContextCancel(ctx, 1*time.Second, true, func(ctx context.Context) (bool, error) {
nodeName := os.Getenv("NODE_NAME")
if nodeName == "" {
return false, nil
}
node, err := nodes.Get(ctx, nodeName, metav1.GetOptions{})
if err != nil {
logrus.Debugf("Failed to update P2P address annotations and labels: %v", err)
return false, nil
}
if node.Annotations == nil {
node.Annotations = map[string]string{}
}
node.Annotations[P2pAddressAnnotation] = id
if node.Labels == nil {
node.Labels = map[string]string{}
}
node.Labels[P2pEnabledLabel] = "true"
if _, err = nodes.Update(ctx, node, metav1.UpdateOptions{}); err != nil {
logrus.Debugf("Failed to update P2P address annotations and labels: %v", err)
return false, nil
}
logrus.Infof("Node P2P address annotations and labels added: %s", id)
return true, nil
})
return waitForDone(ctx)
}
func (c *agentBootstrapper) Get(ctx context.Context) ([]peer.AddrInfo, error) {
if c.server == "" || c.token == "" {
return nil, errors.New("cannot get addresses without server and token")
}
if c.info == nil {
return nil, errors.New("client not ready")
}
addr, err := c.info.Get("/v1-"+version.Program+"/p2p", clientaccess.WithHeader("Accept", "application/json"))
if err != nil {
return nil, err
}
// If the response cannot be decoded as a JSON list of addresses, fall back
// to using it as a legacy single-address response.
addrs := []string{}
if err := json.Unmarshal(addr, &addrs); err != nil {
addrs = append(addrs, string(addr))
}
addrInfos := []peer.AddrInfo{}
for _, addr := range addrs {
if addrInfo, err := peer.AddrInfoFromString(addr); err == nil {
addrInfos = append(addrInfos, *addrInfo)
}
}
return addrInfos, nil
}
type serverBootstrapper struct {
controlConfig *config.Control
}
// NewServerBootstrapper returns a p2p bootstrapper that returns an address from the Kubernetes node list
func NewServerBootstrapper(controlConfig *config.Control) routing.Bootstrapper {
return &serverBootstrapper{
controlConfig: controlConfig,
}
}
func (s *serverBootstrapper) Run(ctx context.Context, _ string) error {
return waitForDone(ctx)
}
func (s *serverBootstrapper) Get(ctx context.Context) ([]peer.AddrInfo, error) {
if s.controlConfig.Runtime.Core == nil {
return nil, util.ErrCoreNotReady
}
nodeName := os.Getenv("NODE_NAME")
if nodeName == "" {
return nil, errors.New("node name not set")
}
nodes := s.controlConfig.Runtime.Core.Core().V1().Node()
if !nodes.Informer().HasSynced() {
return nil, errors.New("node cache informer not synced")
}
labelSelector := labels.Set{P2pEnabledLabel: "true"}.AsSelector()
nodeList, err := nodes.Cache().List(labelSelector)
if err != nil {
return nil, err
}
addrs := []peer.AddrInfo{}
for _, node := range nodeList {
if node.Name == nodeName {
// don't return our own address
continue
}
if find, condition := nodeutil.GetNodeCondition(&node.Status, v1.NodeReady); find == -1 || condition.Status != v1.ConditionTrue {
// don't return the address of a not-ready node
continue
}
if val, ok := node.Annotations[P2pAddressAnnotation]; ok {
for _, addr := range strings.Split(val, ",") {
if info, err := peer.AddrInfoFromString(addr); err == nil {
addrs = append(addrs, *info)
}
}
}
}
return addrs, nil
}
type chainingBootstrapper struct {
bootstrappers []routing.Bootstrapper
}
// NewChainingBootstrapper returns a p2p bootstrapper that passes through to a list of bootstrappers.
// Addressess are returned from the first bootstrapper that returns successfully, to prevent infinite
// recursion if this chains through an agentBootstrapper when the server URL is set to an external
// loadbalancer that points back at this node.
func NewChainingBootstrapper(bootstrappers ...routing.Bootstrapper) routing.Bootstrapper {
return &chainingBootstrapper{
bootstrappers: bootstrappers,
}
}
func (c *chainingBootstrapper) Run(ctx context.Context, id string) error {
eg, ctx := errgroup.WithContext(ctx)
for i := range c.bootstrappers {
b := c.bootstrappers[i]
eg.Go(func() error {
return b.Run(ctx, id)
})
}
return eg.Wait()
}
func (c *chainingBootstrapper) Get(ctx context.Context) ([]peer.AddrInfo, error) {
errs := merr.Errors{}
for i := range c.bootstrappers {
b := c.bootstrappers[i]
as, err := b.Get(ctx)
if err != nil {
errs = append(errs, err)
} else if len(as) != 0 {
return as, nil
}
}
return nil, merr.NewErrors(errs...)
}
func waitForDone(ctx context.Context) error {
<-ctx.Done()
if err := ctx.Err(); err != nil && !errors.Is(err, context.Canceled) {
return err
}
return nil
}