dangerous unzip

main.go

package main

import (
	"archive/zip"
	"fmt"
	"io"
	"log"
	"os"
	"path/filepath"
)

// copy from https://stackoverflow.com/a/24792688/2737403
func Unzip(src, dest string) error {
	r, err := zip.OpenReader(src)
	if err != nil {
		return err
	}
	defer func() {
		if err := r.Close(); err != nil {
			panic(err)
		}
	}()

	os.MkdirAll(dest, 0755)

	// Closure to address file descriptors issue with all the deferred .Close() methods
	extractAndWriteFile := func(f *zip.File) error {
		rc, err := f.Open()
		if err != nil {
			return err
		}
		defer func() {
			if err := rc.Close(); err != nil {
				panic(err)
			}
		}()

		path := filepath.Join(dest, f.Name)
		fmt.Println(f.Name)

		if f.FileInfo().IsDir() {
			os.MkdirAll(path, f.Mode())
		} else {
			os.MkdirAll(filepath.Dir(path), f.Mode())
			f, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode())
			if err != nil {
				return err
			}
			defer func() {
				if err := f.Close(); err != nil {
					panic(err)
				}
			}()

			_, err = io.Copy(f, rc)
			if err != nil {
				return err
			}
		}
		return nil
	}

	for _, f := range r.File {
		err := extractAndWriteFile(f)
		if err != nil {
			return err
		}
	}

	return nil
}

func main() {
	// copy from https://golang.org/pkg/archive/zip/#example_Writer
	// Create a buffer to write our archive to.
	f, err := os.Create("/tmp/test.zip")
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()

	// Create a new zip archive.
	w := zip.NewWriter(f)

	// Add some files to the archive.
	var files = []struct {
		Name, Body string
	}{
		{"../../test.txt", "i am test"},
		{"../foo.txt", "i am foo"},
		{"bar.txt", "i am bar"},

	}
	for _, file := range files {
		f, err := w.Create(file.Name)
		if err != nil {
			log.Fatal(err)
		}
		_, err = f.Write([]byte(file.Body))
		if err != nil {
			log.Fatal(err)
		}
	}

	// Make sure to check the error on Close.
	err = w.Close()
	if err != nil {
		log.Fatal(err)
	}

	err = Unzip("/tmp/test.zip", "/tmp/dir1/dir2")
	if err != nil {
		log.Fatal(err)
	}
}

/tmp/dir1
├── dir2
│   └── bar.txt
└── foo.txt

1 directory, 2 files