k3s/vendor/k8s.io/kubernetes/pkg/kubelet/images/puller.go

96 lines
2.9 KiB
Go

/*
Copyright 2016 The Kubernetes 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 images
import (
"time"
"k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/util/wait"
runtimeapi "k8s.io/cri-api/pkg/apis/runtime/v1alpha2"
kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
)
type pullResult struct {
imageRef string
err error
}
type imagePuller interface {
pullImage(kubecontainer.ImageSpec, []v1.Secret, chan<- pullResult, *runtimeapi.PodSandboxConfig)
}
var _, _ imagePuller = &parallelImagePuller{}, &serialImagePuller{}
type parallelImagePuller struct {
imageService kubecontainer.ImageService
}
func newParallelImagePuller(imageService kubecontainer.ImageService) imagePuller {
return &parallelImagePuller{imageService}
}
func (pip *parallelImagePuller) pullImage(spec kubecontainer.ImageSpec, pullSecrets []v1.Secret, pullChan chan<- pullResult, podSandboxConfig *runtimeapi.PodSandboxConfig) {
go func() {
imageRef, err := pip.imageService.PullImage(spec, pullSecrets, podSandboxConfig)
pullChan <- pullResult{
imageRef: imageRef,
err: err,
}
}()
}
// Maximum number of image pull requests than can be queued.
const maxImagePullRequests = 10
type serialImagePuller struct {
imageService kubecontainer.ImageService
pullRequests chan *imagePullRequest
}
func newSerialImagePuller(imageService kubecontainer.ImageService) imagePuller {
imagePuller := &serialImagePuller{imageService, make(chan *imagePullRequest, maxImagePullRequests)}
go wait.Until(imagePuller.processImagePullRequests, time.Second, wait.NeverStop)
return imagePuller
}
type imagePullRequest struct {
spec kubecontainer.ImageSpec
pullSecrets []v1.Secret
pullChan chan<- pullResult
podSandboxConfig *runtimeapi.PodSandboxConfig
}
func (sip *serialImagePuller) pullImage(spec kubecontainer.ImageSpec, pullSecrets []v1.Secret, pullChan chan<- pullResult, podSandboxConfig *runtimeapi.PodSandboxConfig) {
sip.pullRequests <- &imagePullRequest{
spec: spec,
pullSecrets: pullSecrets,
pullChan: pullChan,
podSandboxConfig: podSandboxConfig,
}
}
func (sip *serialImagePuller) processImagePullRequests() {
for pullRequest := range sip.pullRequests {
imageRef, err := sip.imageService.PullImage(pullRequest.spec, pullRequest.pullSecrets, pullRequest.podSandboxConfig)
pullRequest.pullChan <- pullResult{
imageRef: imageRef,
err: err,
}
}
}