问题内容
我的查询与标题差不多，我有一个本地文件 file.txt ，我想将其复制到 pod1 的容器 container1 中。
如果我使用 kubectl 来执行此操作，适当的命令是：
kubectl cp file.txt pod1:file.txt -c container1
但是，如何使用 kubectl 的 go 客户端来实现呢？
我尝试了两种方法，但都不起作用：
import (
"fmt"
"context"
"log"
"os"
"path/filepath"
g "github.com/sdslabs/katana/configs"
v1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/labels"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/rest"
"k8s.io/client-go/tools/clientcmd"
//"k8s.io/kubectl/pkg/cmd/exec"
)
func copyintopod(namespace string, podname string, containername string, srcpath string, dstpath string) {
// create a kubernetes client
config, err := getkubeconfig()
if err != nil {
log.fatal(err)
}
client, err := kubernetes.newforconfig(config)
if err != nil {
log.fatal(err)
}
// build the command to execute
cmd := []string{"cp", srcpath, dstpath}
// use the podexecoptions struct to specify the options for the exec request
options := v1.podexecoptions{
container: containername,
command: cmd,
stdin: false,
stdout: true,
stderr: true,
tty: false,
}
log.println("options set!")
// use the corev1api.exec method to execute the command inside the container
req := client.corev1().restclient().post().
namespace(namespace).
name(podname).
resource("pods").
subresource("exec").
versionedparams(&options, metav1.parametercodec)
log.println("request generated")
exec, err := req.stream(context.todo())
if err != nil {
log.fatal(err)
}
defer exec.close()
// read the response from the exec command
var result []byte
if _, err := exec.read(result); err != nil {
log.fatal(err)
}
fmt.println("file copied successfully!")
}
这给了我错误消息：
no 类型已在方案“pkg/runtime/scheme.go:100” 中为 v1.podexecoptions 类型注册
我无法弄清楚，所以我尝试了另一种方法：
type PodExec struct {
RestConfig *rest.Config
*kubernetes.Clientset
}
func NewPodExec(config *rest.Config, clientset *kubernetes.Clientset) *PodExec {
config.APIPath = "/api" // Make sure we target /api and not just /
config.GroupVersion = &schema.GroupVersion{Version: "v1"} // this targets the core api groups so the url path will be /api/v1
config.NegotiatedSerializer = serializer.WithoutConversionCodecFactory{CodecFactory: scheme.Codecs}
return &PodExec{
RestConfig: config,
Clientset: clientset,
}
}
func (p *PodExec) PodCopyFile(src string, dst string, containername string, podNamespace string) (*bytes.Buffer, *bytes.Buffer, *bytes.Buffer, error) {
ioStreams, in, out, errOut := genericclioptions.NewTestIOStreams()
copyOptions := cp.NewCopyOptions(ioStreams)
copyOptions.Clientset = p.Clientset
copyOptions.ClientConfig = p.RestConfig
copyOptions.Container = containername
copyOptions.Namespace = podNamespace
err := copyOptions.Run()
if err != nil {
return nil, nil, nil, fmt.Errorf("could not run copy operation: %v", err)
}
return in, out, errOut, nil
}
但是，copyoptions.run()命令存在一些问题，它尝试在copyoptions内查找o.args[0]和o.args[0]，但o未导入，因此无法导入进行修改。
上下文：https://pkg.go.dev/k8s.io/kubectl/pkg/cmd/cp#copyoptions.run
所以，现在我真的很迷失和困惑。任何帮助，将不胜感激。谢谢。
编辑：我确实想到了一个可行的方法，我们可以直接调用 cmd.exec() 并直接运行 kubectl cp 命令，但看起来有点老套，我不确定它是否有效，有什么想法吗？
正确答案
这就是我最终成功做到这一点的方法：
package main
import (
"context"
"fmt"
"os"
"path/filepath"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/kubernetes/scheme"
corev1 "k8s.io/api/core/v1"
"k8s.io/client-go/tools/clientcmd"
"k8s.io/client-go/util/homedir"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/client-go/tools/remotecommand"
)
func CopyIntoPod(podName string, namespace string, containerName string, srcPath string, dstPath string) {
// Get the default kubeconfig file
kubeConfig := filepath.Join(homedir.HomeDir(), ".kube", "config")
// Create a config object using the kubeconfig file
config, err := clientcmd.BuildConfigFromFlags("", kubeConfig)
if err != nil {
fmt.Printf("Error creating config: %s\n", err)
return
}
// Create a Kubernetes client
client, err := kubernetes.NewForConfig(config)
if err != nil {
fmt.Printf("Error creating client: %s\n", err)
return
}
// Open the file to copy
localFile, err := os.Open(srcPath)
if err != nil {
fmt.Printf("Error opening local file: %s\n", err)
return
}
defer localFile.Close()
pod, err := client.CoreV1().Pods(namespace).Get(context.TODO(), podName, metav1.GetOptions{})
if err != nil {
fmt.Printf("Error getting pod: %s\n", err)
return
}
// Find the container in the pod
var container *corev1.Container
for _, c := range pod.Spec.Containers {
if c.Name == containerName {
container = &c
break
}
}
if container == nil {
fmt.Printf("Container not found in pod\n")
return
}
// Create a stream to the container
req := client.CoreV1().RESTClient().Post().
Resource("pods").
Name(podName).
Namespace(namespace).
SubResource("exec").
Param("container", containerName)
req.VersionedParams(&corev1.PodExecOptions{
Container: containerName,
Command: []string{"bash", "-c", "cat > " + dstPath},
Stdin: true,
Stdout: true,
Stderr: true,
}, scheme.ParameterCodec)
exec, err := remotecommand.NewSPDYExecutor(config, "POST", req.URL())
if err != nil {
fmt.Printf("Error creating executor: %s\n", err)
return
}
// Create a stream to the container
err = exec.StreamWithContext(context.TODO(), remotecommand.StreamOptions{
Stdin: localFile,
Stdout: os.Stdout,
Stderr: os.Stderr,
Tty: false,
})
if err != nil {
fmt.Printf("Error streaming: %s\n", err)
return
}
fmt.Println("File copied successfully")
} 
