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努力的gopher
我们在平时经常用到 tar.gz 的解压与压缩，使用命令行大家都了解，tar -zcvf 与 tar -xvf 。今天我把我用go语言实现的压缩解压写下来，大家如果用到可以收藏下来，以后避免重复造轮子，个人觉得这个很值得在自己本地或者项目中保存起来，当作一个lib使用。不多说，下面是代码实现，本人目前也在用这个代码，还没有发现bug，如果有人发现bug请留言。
package fs
import (
"archive/tar"
"compress/gzip"
"errors"
"io"
"os"
"path"
"path/filepath"
)
// UnTarGz takes a destination path and a reader; a tar reader loops over the tar.gz file
// creating the file structure at 'dst' along the way, and writing any files
func UnTarGz(dst string, r io.Reader) error {
gzr, err := gzip.NewReader(r)
if err != nil {
return err
}
defer func() {
if e := gzr. Close (); e != nil {
return
}
}()
tr := tar.NewReader(gzr)
for {
Header , err := tr.Next()
switch {
// if no more files are found return
case err == io. EOF :
return nil
// return any other error
case err != nil:
return err
// if the header is nil, just skip it (not sure how this happens)
case header == nil:
continue
}
// the target location where the dir/file should be created
target := filepath.Join(dst, header.Name)
// the following switch could also be done using fi.Mode(), not sure if there
// a benefit of using one vs. the other.
// fi := header.FileInfo()
// check the file type
switch header.Typeflag {
// if its a dir and it doesn't exist create it
case tar.TypeDir:
if _, err := os. Stat (target); err != nil {
if err := os.MkdirAll(target, 0750); err != nil {
return err
}
}
// if it's a file create it
case tar.TypeReg:
f, err := os.OpenFile(target, os.O_CREATE|os.O_RDWR, os.FileMode(header.Mode))
if err != nil {
return err
}
// copy over contents
if _, err = io.Copy(f, tr); err != nil {
return err
}
// manually close here after each file operation; defering would cause each file close
// to wait until all operations have completed.
if err = f.Close(); err != nil {
return err
}
}
}
}
// TarGz tar for srcPath and create destFile
// flag = 0,not contains srcPath dir, flag = 1, contains srcPath
func TarGz(srcPath string, destFile string, flag int) error {
fw, err := os.Create(destFile)
if err != nil {
return err
}
defer fw.Close()
// Gzip writer
gw := gzip.NewWriter(fw)
defer gw.Close()
// Tar writer
tw := tar.NewWriter(gw)
defer tw.Close()
// Check if it's a file or a directory
f, err := os.Open(srcPath)
if err != nil {
return err
}
fi, err := f.Stat()
if err != nil {
return err
}
if fi.IsDir() {
// handle source directory
if flag == 0 {
err := tarGzDir(srcPath, path.Base(""), tw)
if err != nil {
return err
}
} else if flag == 1 {
err := tarGzFile(srcPath, path.Base(srcPath), tw, fi)
if err != nil {
return err
}
err = tarGzDir(srcPath, path.Base(srcPath), tw)
if err != nil {
return err
}
} else {
return errors.New("Invlaid flag")
}
} else {
// handle file directly
if flag == 0 {
err := tarGzFile(srcPath, path.Base(""), tw, fi)
if err != nil {
return err
}
} else if flag == 1 {
err := tarGzFile(srcPath, path.Base(srcPath), tw, fi)
if err != nil {
return err
}
} else {
return errors.New("Invlaid flag")
}
}
return nil
}
func tarGzDir(srcDir string, recPath string, tw *tar.Writer) error {
// Open source diretory
dir, err := os.Open(srcDir)
if err != nil {
return err
}
defer dir.Close()
// Get file info slice
fis, err := dir.Readdir(0)
if err != nil {
return err
}
for _, fi := range fis {
// Append path
curPath := srcDir + "/" + fi.Name()
err := tarGzFile(curPath, recPath+"/"+fi.Name(), tw, fi)
if err != nil {
return err
}
// Check it is directory or file
if fi.IsDir() {
// Directory
// (Directory won't add unitl all subfiles are added)
err := tarGzDir(curPath, recPath+"/"+fi.Name(), tw)
if err != nil {
return err
}
}
}
return nil
}
func tarGzFile(srcFile string, recPath string, tw *tar.Writer, fi os.FileInfo) error {
if fi.IsDir() {
// Create tar header
hdr := new(tar.Header)
// if last character of header name is '/' it also can be directory
// but if you don't set Typeflag, error will occur when you untargz
hdr.Name = recPath + "/"
hdr.Typeflag = tar.TypeDir
hdr.Size = 0
hdr.Mode = int64(fi.Mode())
hdr.ModTime = fi.ModTime()
// Write hander
err := tw.WriteHeader(hdr)
if err != nil {
return err
}
} else {
// File reader
fr, err := os.Open(srcFile)
if err != nil {
return err
}
defer fr.Close()
// Create tar header
hdr := new(tar.Header)
hdr.Typeflag = tar.TypeReg
hdr.Name = recPath
hdr.Size = fi.Size()
hdr.Mode = int64(fi.Mode())
hdr.ModTime = fi.ModTime()
// Write hander
err = tw.WriteHeader(hdr)
if err != nil {
return err
}
// Write file data
_, err = io.Copy(tw, fr)
if err != nil {
return err
}
}
return nil
}
