Kubernetes集群中Pod间文件拷贝

谁借莪１个温暖的怀抱￠ 2023-09-30 10:07 22阅读 0赞

如何在Pod间拷贝文件？

具体代码如下：

/*
     copy file to pod
    */
    package cp
    
    import (
    	"archive/tar"
    	"context"
    	"fmt"
    	"io"
    	"io/ioutil"
    	"log"
    	"os"
    	"path"
    	"strings"
    
    	corev1 "k8s.io/api/core/v1"
    	"k8s.io/client-go/kubernetes"
    	"k8s.io/client-go/kubernetes/scheme"
    	"k8s.io/client-go/rest"
    	"k8s.io/client-go/tools/remotecommand"
    )
    
    type Pod struct {
    	Name          string
    	Namespace     string
    	ContainerName string
    }
    
    func (i *Pod) CopyToPod(ctx context.Context, client *kubernetes.Clientset, config *rest.Config, srcPath string, destPath string) error {
    	reader, writer := io.Pipe()
    
    	if destPath != "/" && strings.HasSuffix(string(destPath[len(destPath)-1]), "/") {
    		destPath = destPath[:len(destPath)-1]
    	}
    
    	if err := checkDestinationIsDir(ctx, client, config, i, destPath); err == nil {
    		destPath = destPath + "/" + path.Base(srcPath)
    	}
    
    	go func() {
    		defer writer.Close()
    		err := makeTar(srcPath, destPath, writer)
    		if err != nil {
    			fmt.Println(err)
    		}
    	}()
    
    	var cmdArr []string
    
    	cmdArr = []string{"tar", "-xf", "-"}
    	destDir := path.Dir(destPath)
    	if len(destDir) > 0 {
    		cmdArr = append(cmdArr, "-C", destDir)
    	}
    	//remote shell.
    	req := client.CoreV1().RESTClient().
    		Post().
    		Namespace(i.Namespace).
    		Resource("pods").
    		Name(i.Name).
    		SubResource("exec").
    		VersionedParams(&corev1.PodExecOptions{
    			Container: i.ContainerName,
    			Command:   cmdArr,
    			Stdin:     true,
    			Stdout:    true,
    			Stderr:    true,
    			TTY:       false,
    		}, scheme.ParameterCodec)
    
    	exec, err := remotecommand.NewSPDYExecutor(config, "POST", req.URL())
    	if err != nil {
    		return err
    	}
    
    	err = exec.Stream(remotecommand.StreamOptions{
    		Stdin:  reader,
    		Stdout: os.Stdout,
    		Stderr: os.Stderr,
    		Tty:    false,
    	})
    	if err != nil {
    		return err
    	}
    	return nil
    }
    
    func checkDestinationIsDir(ctx context.Context, client *kubernetes.Clientset, config *rest.Config, i *Pod, destPath string) error {
    	return i.Exec(ctx, client, config, []string{"test", "-d", destPath})
    }
    
    func makeTar(srcPath, destPath string, writer io.Writer) error {
    	// TODO: use compression here?
    	tarWriter := tar.NewWriter(writer)
    	defer tarWriter.Close()
    
    	srcPath = path.Clean(srcPath)
    	destPath = path.Clean(destPath)
    	return recursiveTar(path.Dir(srcPath), path.Base(srcPath), path.Dir(destPath), path.Base(destPath), tarWriter)
    }
    
    func recursiveTar(srcBase, srcFile, destBase, destFile string, tarWriter *tar.Writer) error {
    
    	// defer func() {
    	// 	fmt.Println("d")
    	// 	if err := recover(); err != nil {
    	// 		fmt.Println(err) // 这里的err其实就是panic传入的内容
    	// 	}
    	// 	fmt.Println("e")
    	// }()
    
    	filepath := path.Join(srcBase, srcFile)
    	stat, err := os.Lstat(filepath)
    	if err != nil {
    		return err
    	}
    	if stat.IsDir() {
    		files, err := ioutil.ReadDir(filepath)
    		if err != nil {
    			return err
    		}
    		if len(files) == 0 {
    			//case empty directory
    			hdr, _ := tar.FileInfoHeader(stat, filepath)
    			hdr.Name = destFile
    			if err := tarWriter.WriteHeader(hdr); err != nil {
    				return err
    			}
    		}
    		for _, f := range files {
    			if err := recursiveTar(srcBase, path.Join(srcFile, f.Name()), destBase, path.Join(destFile, f.Name()), tarWriter); err != nil {
    				return err
    			}
    		}
    		return nil
    	} else if stat.Mode()&os.ModeSymlink != 0 {
    		//case soft link
    		hdr, _ := tar.FileInfoHeader(stat, filepath)
    		target, err := os.Readlink(filepath)
    		if err != nil {
    			return err
    		}
    
    		hdr.Linkname = target
    		hdr.Name = destFile
    		if err := tarWriter.WriteHeader(hdr); err != nil {
    			return err
    		}
    	} else {
    		//case regular file or other file type like pipe
    		hdr, err := tar.FileInfoHeader(stat, filepath)
    		if err != nil {
    			return err
    		}
    		hdr.Name = destFile
    		err = tarWriter.WriteHeader(hdr)
    		if err != nil {
    			log.Println(err)
    			return err
    		}
    
    		f, err := os.Open(filepath)
    		if err != nil {
    			return err
    		}
    		defer f.Close()
    
    		if _, err := io.Copy(tarWriter, f); err != nil {
    			return err
    		}
    		return f.Close()
    	}
    	return nil
    }
    
    func (i *Pod) Exec(ctx context.Context, client *kubernetes.Clientset, config *rest.Config, cmd []string) error {
    
    	req := client.CoreV1().RESTClient().
    		Post().
    		Namespace(i.Namespace).
    		Resource("pods").
    		Name(i.Name).
    		SubResource("exec").
    		VersionedParams(&corev1.PodExecOptions{
    			Container: i.ContainerName,
    			Command:   cmd,
    			Stdin:     true,
    			Stdout:    true,
    			Stderr:    true,
    			TTY:       false,
    		}, scheme.ParameterCodec)
    
    	exec, err := remotecommand.NewSPDYExecutor(config, "POST", req.URL())
    	if err != nil {
    		return err
    	}
    
    	err = exec.Stream(remotecommand.StreamOptions{
    		Stdin:  strings.NewReader(""),
    		Stdout: os.Stdout,
    		Stderr: os.Stderr,
    		Tty:    false,
    	})
    
    	if err != nil {
    		return err
    	}
    	return nil
    }