打包文件用到了tar包,其中tar包的用法可以参考API
golang提供了个函数用来遍历文件夹 filepath.Walk
函数具体描述如下:
func Walk(root string, walkFn WalkFunc) error root是用遍历的文件夹
type WalkFunc
type WalkFunc func(path string, info os.FileInfo, err error) error path参数是返回遍历的文件路径和文件信息
在使用中如代码中蓝色部分,通过该方法呢,我们可以对文件和文件夹的操作更加熟悉,其中用到了
os.Create 用来创建文件,返回文件信息和错误信息 func Create(name string) (file *File, err error)
os.Remove 用来删除文件,返回错误信息 func Remove(name string) error
os.Stat 用来返回文件具体信息,返回文件信息和错误信息 func (f *File) Stat() (fi FileInfo, err error)
os.Open 用来打开文件,返回文件信息和错误信息 func Open(name string) (file *File, err error)
io.Copy 复职文件信息到Writer func Copy(dst Writer, src Reader) (written int64, err error)func CopyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error)
os.Mkdir 用来创建文件夹,返回错误信息 func Mkdir(name string, perm FileMode) errorstrings.TrimPrefix(targetpath, directory) 这个方法获取具体的文件路径相对目标文件夹的相对路径,也是在tar包中创建文件夹的相对路径
package main
import (
"archive/tar"
"fmt"
"io"
"os"
"path/filepath"
"strings"
)
/***生成***/
func createTar(filesource, filetarget string, deleteIfExist bool) error {
//create tar file with targetfile name
tarfile, err := os.Create(filetarget)
if err != nil {
// if file is exist then delete file
if err == os.ErrExist {
if err := os.Remove(filetarget); err != nil {
fmt.Println(err)
return err
}
} else {
fmt.Println(err)
return err
}
}
defer tarfile.Close()
tarwriter := tar.NewWriter(tarfile)
sfileInfo, err := os.Stat(filesource)
if err != nil {
fmt.Println(err)
return err
}
if !sfileInfo.IsDir() {
return tarFile(filetarget, filesource, sfileInfo, tarwriter)
} else {
return tarFolder(filesource, tarwriter)
}
return nil
}
func tarFile(directory string, filesource string, sfileInfo os.FileInfo, tarwriter *tar.Writer) error {
sfile, err := os.Open(filesource)
if err != nil {
panic(err)
return err
}
defer sfile.Close()
header, err := tar.FileInfoHeader(sfileInfo, "")
if err != nil {
fmt.Println(err)
return err
}
header.Name = directory
err = tarwriter.WriteHeader(header)
if err != nil {
fmt.Println(err)
return err
}
// can use buffer to copy the file to tar writer
// buf := make([]byte,15)
// if _, err = io.CopyBuffer(tarwriter, sfile, buf); err != nil {
// panic(err)
// return err
// }
if _, err = io.Copy(tarwriter, sfile); err != nil {
fmt.Println(err)
panic(err)
return err
}
return nil
}
func tarFolder(directory string, tarwriter *tar.Writer) error {
var baseFolder string = filepath.Base(directory)
//fmt.Println(baseFolder)
return filepath.Walk(directory, func(targetpath string, file os.FileInfo, err error) error {
//read the file failure
if file == nil {
panic(err)
return err
}
if file.IsDir() {
// information of file or folder
header, err := tar.FileInfoHeader(file, "")
if err != nil {
return err
}
header.Name = filepath.Join(baseFolder, strings.TrimPrefix(targetpath, directory))
fmt.Println(hdr.Name)
if err = tarwriter.WriteHeader(header); err != nil {
return err
}
os.Mkdir(strings.TrimPrefix(baseFolder, file.Name()), os.ModeDir)
return nil
} else {
//baseFolder is the tar file path
var fileFolder = filepath.Join(baseFolder, strings.TrimPrefix(targetpath, directory))
return tarFile(fileFolder, targetpath, file, tarwriter)
}
})
}