actions-runner-controller/controllers/runner_pod_controller.go

409 lines
13 KiB
Go

/*
Copyright 2020 The actions-runner-controller authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package controllers
import (
"context"
"errors"
"fmt"
"time"
"github.com/go-logr/logr"
gogithub "github.com/google/go-github/v39/github"
"k8s.io/apimachinery/pkg/util/wait"
kerrors "k8s.io/apimachinery/pkg/api/errors"
"k8s.io/apimachinery/pkg/runtime"
"k8s.io/client-go/tools/record"
ctrl "sigs.k8s.io/controller-runtime"
"sigs.k8s.io/controller-runtime/pkg/client"
corev1 "k8s.io/api/core/v1"
"github.com/actions-runner-controller/actions-runner-controller/github"
)
// RunnerPodReconciler reconciles a Runner object
type RunnerPodReconciler struct {
client.Client
Log logr.Logger
Recorder record.EventRecorder
Scheme *runtime.Scheme
GitHubClient *github.Client
Name string
RegistrationRecheckInterval time.Duration
RegistrationRecheckJitter time.Duration
UnregistrationTimeout time.Duration
UnregistrationRetryDelay time.Duration
}
const (
// This names requires at least one slash to work.
// See https://github.com/google/knative-gcp/issues/378
runnerPodFinalizerName = "actions.summerwind.dev/runner-pod"
AnnotationKeyLastRegistrationCheckTime = "actions-runner-controller/last-registration-check-time"
)
// +kubebuilder:rbac:groups=core,resources=pods,verbs=get;list;watch;update;patch;delete
// +kubebuilder:rbac:groups=core,resources=events,verbs=create;patch
func (r *RunnerPodReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
log := r.Log.WithValues("runnerpod", req.NamespacedName)
var runnerPod corev1.Pod
if err := r.Get(ctx, req.NamespacedName, &runnerPod); err != nil {
return ctrl.Result{}, client.IgnoreNotFound(err)
}
_, isRunnerPod := runnerPod.Labels[LabelKeyRunnerSetName]
if !isRunnerPod {
return ctrl.Result{}, nil
}
var enterprise, org, repo string
envvars := runnerPod.Spec.Containers[0].Env
for _, e := range envvars {
switch e.Name {
case EnvVarEnterprise:
enterprise = e.Value
case EnvVarOrg:
org = e.Value
case EnvVarRepo:
repo = e.Value
}
}
if runnerPod.ObjectMeta.DeletionTimestamp.IsZero() {
finalizers, added := addFinalizer(runnerPod.ObjectMeta.Finalizers, runnerPodFinalizerName)
if added {
newRunner := runnerPod.DeepCopy()
newRunner.ObjectMeta.Finalizers = finalizers
if err := r.Patch(ctx, newRunner, client.MergeFrom(&runnerPod)); err != nil {
log.Error(err, "Failed to update runner")
return ctrl.Result{}, err
}
return ctrl.Result{}, nil
}
} else {
finalizers, removed := removeFinalizer(runnerPod.ObjectMeta.Finalizers, runnerPodFinalizerName)
if removed {
updatedPod, res, err := tickRunnerGracefulStop(ctx, r.unregistrationTimeout(), r.unregistrationRetryDelay(), log, r.GitHubClient, r.Client, enterprise, org, repo, runnerPod.Name, &runnerPod)
if res != nil {
return *res, err
}
patchedPod := updatedPod.DeepCopy()
patchedPod.ObjectMeta.Finalizers = finalizers
// We commit the removal of the finalizer so that Kuberenetes notices it and delete the pod resource from the cluster.
if err := r.Patch(ctx, patchedPod, client.MergeFrom(&runnerPod)); err != nil {
log.Error(err, "Failed to update runner for finalizer removal")
return ctrl.Result{}, err
}
log.Info("Removed runner from GitHub", "repository", repo, "organization", org)
}
deletionTimeout := 1 * time.Minute
currentTime := time.Now()
deletionDidTimeout := currentTime.Sub(runnerPod.DeletionTimestamp.Add(deletionTimeout)) > 0
if deletionDidTimeout {
log.Info(
fmt.Sprintf("Failed to delete pod within %s. ", deletionTimeout)+
"This is typically the case when a Kubernetes node became unreachable "+
"and the kube controller started evicting nodes. Forcefully deleting the pod to not get stuck.",
"podDeletionTimestamp", runnerPod.DeletionTimestamp,
"currentTime", currentTime,
"configuredDeletionTimeout", deletionTimeout,
)
var force int64 = 0
// forcefully delete runner as we would otherwise get stuck if the node stays unreachable
if err := r.Delete(ctx, &runnerPod, &client.DeleteOptions{GracePeriodSeconds: &force}); err != nil {
// probably
if !kerrors.IsNotFound(err) {
log.Error(err, "Failed to forcefully delete pod resource ...")
return ctrl.Result{}, err
}
// forceful deletion finally succeeded
return ctrl.Result{Requeue: true}, nil
}
r.Recorder.Event(&runnerPod, corev1.EventTypeNormal, "PodDeleted", fmt.Sprintf("Forcefully deleted pod '%s'", runnerPod.Name))
log.Info("Forcefully deleted runner pod", "repository", repo)
// give kube manager a little time to forcefully delete the stuck pod
return ctrl.Result{RequeueAfter: 3 * time.Second}, nil
}
return ctrl.Result{}, nil
}
// If pod has ended up succeeded we need to restart it
// Happens e.g. when dind is in runner and run completes
stopped := runnerPod.Status.Phase == corev1.PodSucceeded
if !stopped {
if runnerPod.Status.Phase == corev1.PodRunning {
for _, status := range runnerPod.Status.ContainerStatuses {
if status.Name != containerName {
continue
}
if status.State.Terminated != nil && status.State.Terminated.ExitCode == 0 {
stopped = true
}
}
}
}
restart := stopped
var registrationRecheckDelay time.Duration
// all checks done below only decide whether a restart is needed
// if a restart was already decided before, there is no need for the checks
// saving API calls and scary log messages
if !restart {
registrationCheckInterval := time.Minute
if r.RegistrationRecheckInterval > 0 {
registrationCheckInterval = r.RegistrationRecheckInterval
}
lastCheckTimeStr := runnerPod.Annotations[AnnotationKeyLastRegistrationCheckTime]
var lastCheckTime *time.Time
if lastCheckTimeStr != "" {
t, err := time.Parse(time.RFC3339, lastCheckTimeStr)
if err != nil {
log.Error(err, "failed to parase last check time %q", lastCheckTimeStr)
return ctrl.Result{}, nil
}
lastCheckTime = &t
}
// We want to call ListRunners GitHub Actions API only once per runner per minute.
// This if block, in conjunction with:
// return ctrl.Result{RequeueAfter: registrationRecheckDelay}, nil
// achieves that.
if lastCheckTime != nil {
nextCheckTime := lastCheckTime.Add(registrationCheckInterval)
now := time.Now()
// Requeue scheduled by RequeueAfter can happen a bit earlier (like dozens of milliseconds)
// so to avoid excessive, in-effective retry, we heuristically ignore the remaining delay in case it is
// shorter than 1s
requeueAfter := nextCheckTime.Sub(now) - time.Second
if requeueAfter > 0 {
log.Info(
fmt.Sprintf("Skipped registration check because it's deferred until %s. Retrying in %s at latest", nextCheckTime, requeueAfter),
"lastRegistrationCheckTime", lastCheckTime,
"registrationCheckInterval", registrationCheckInterval,
)
// Without RequeueAfter, the controller may not retry on scheduled. Instead, it must wait until the
// next sync period passes, which can be too much later than nextCheckTime.
//
// We need to requeue on this reconcilation even though we have already scheduled the initial
// requeue previously with `return ctrl.Result{RequeueAfter: registrationRecheckDelay}, nil`.
// Apparently, the workqueue used by controller-runtime seems to deduplicate and resets the delay on
// other requeues- so the initial scheduled requeue may have been reset due to requeue on
// spec/status change.
return ctrl.Result{RequeueAfter: requeueAfter}, nil
}
}
notFound := false
offline := false
_, err := r.GitHubClient.IsRunnerBusy(ctx, enterprise, org, repo, runnerPod.Name)
currentTime := time.Now()
if err != nil {
var notFoundException *github.RunnerNotFound
var offlineException *github.RunnerOffline
if errors.As(err, &notFoundException) {
notFound = true
} else if errors.As(err, &offlineException) {
offline = true
} else {
var e *gogithub.RateLimitError
if errors.As(err, &e) {
// We log the underlying error when we failed calling GitHub API to list or unregisters,
// or the runner is still busy.
log.Error(
err,
fmt.Sprintf(
"Failed to check if runner is busy due to Github API rate limit. Retrying in %s to avoid excessive GitHub API calls",
retryDelayOnGitHubAPIRateLimitError,
),
)
return ctrl.Result{RequeueAfter: retryDelayOnGitHubAPIRateLimitError}, err
}
return ctrl.Result{}, err
}
}
registrationTimeout := 10 * time.Minute
durationAfterRegistrationTimeout := currentTime.Sub(runnerPod.CreationTimestamp.Add(registrationTimeout))
registrationDidTimeout := durationAfterRegistrationTimeout > 0
if notFound {
if registrationDidTimeout {
log.Info(
"Runner failed to register itself to GitHub in timely manner. "+
"Recreating the pod to see if it resolves the issue. "+
"CAUTION: If you see this a lot, you should investigate the root cause. "+
"See https://github.com/actions-runner-controller/actions-runner-controller/issues/288",
"podCreationTimestamp", runnerPod.CreationTimestamp,
"currentTime", currentTime,
"configuredRegistrationTimeout", registrationTimeout,
)
restart = true
} else {
log.V(1).Info(
"Runner pod exists but we failed to check if runner is busy. Apparently it still needs more time.",
"runnerName", runnerPod.Name,
)
}
} else if offline {
if registrationDidTimeout {
log.Info(
"Already existing GitHub runner still appears offline . "+
"Recreating the pod to see if it resolves the issue. "+
"CAUTION: If you see this a lot, you should investigate the root cause. ",
"podCreationTimestamp", runnerPod.CreationTimestamp,
"currentTime", currentTime,
"configuredRegistrationTimeout", registrationTimeout,
)
restart = true
} else {
log.V(1).Info(
"Runner pod exists but the GitHub runner appears to be still offline. Waiting for runner to get online ...",
"runnerName", runnerPod.Name,
)
}
}
if (notFound || offline) && !registrationDidTimeout {
registrationRecheckJitter := 10 * time.Second
if r.RegistrationRecheckJitter > 0 {
registrationRecheckJitter = r.RegistrationRecheckJitter
}
registrationRecheckDelay = registrationCheckInterval + wait.Jitter(registrationRecheckJitter, 0.1)
}
}
// Don't do anything if there's no need to restart the runner
if !restart {
// This guard enables us to update runner.Status.Phase to `Running` only after
// the runner is registered to GitHub.
if registrationRecheckDelay > 0 {
log.V(1).Info(fmt.Sprintf("Rechecking the runner registration in %s", registrationRecheckDelay))
updated := runnerPod.DeepCopy()
t := time.Now().Format(time.RFC3339)
updated.Annotations[AnnotationKeyLastRegistrationCheckTime] = t
if err := r.Patch(ctx, updated, client.MergeFrom(&runnerPod)); err != nil {
log.Error(err, "Failed to update runner pod annotation for LastRegistrationCheckTime")
return ctrl.Result{}, err
}
return ctrl.Result{RequeueAfter: registrationRecheckDelay}, nil
}
// Seeing this message, you can expect the runner to become `Running` soon.
log.Info(
"Runner appears to have registered and running.",
"podCreationTimestamp", runnerPod.CreationTimestamp,
)
return ctrl.Result{}, nil
}
updated, res, err := tickRunnerGracefulStop(ctx, r.unregistrationTimeout(), r.unregistrationRetryDelay(), log, r.GitHubClient, r.Client, enterprise, org, repo, runnerPod.Name, &runnerPod)
if res != nil {
return *res, err
}
if runnerPodOrContainerIsStopped(updated) {
log.Info("Detected runner to have successfully stopped", "name", runnerPod.Name)
return ctrl.Result{}, nil
} else {
log.Info("Runner can be safely deleted", "name", runnerPod.Name)
}
// Delete current pod if recreation is needed
if err := r.Delete(ctx, updated); err != nil {
log.Error(err, "Failed to delete pod resource")
return ctrl.Result{}, err
}
r.Recorder.Event(&runnerPod, corev1.EventTypeNormal, "PodDeleted", fmt.Sprintf("Deleted pod '%s'", runnerPod.Name))
log.Info("Deleted runner pod", "name", runnerPod.Name)
return ctrl.Result{}, nil
}
func (r *RunnerPodReconciler) unregistrationTimeout() time.Duration {
unregistrationTimeout := DefaultUnregistrationTimeout
if r.UnregistrationTimeout > 0 {
unregistrationTimeout = r.UnregistrationTimeout
}
return unregistrationTimeout
}
func (r *RunnerPodReconciler) unregistrationRetryDelay() time.Duration {
retryDelay := DefaultUnregistrationRetryDelay
if r.UnregistrationRetryDelay > 0 {
retryDelay = r.UnregistrationRetryDelay
}
return retryDelay
}
func (r *RunnerPodReconciler) SetupWithManager(mgr ctrl.Manager) error {
name := "runnerpod-controller"
if r.Name != "" {
name = r.Name
}
r.Recorder = mgr.GetEventRecorderFor(name)
return ctrl.NewControllerManagedBy(mgr).
For(&corev1.Pod{}).
Named(name).
Complete(r)
}