zip_easer.go

package zip_easer_go

import (
	"archive/zip"
	"bytes"
	"io"
	"os"
	"path/filepath"
)

func UnzipFromBytes(data []byte, dest string) error {
	r, err := zip.NewReader(bytes.NewReader(data), int64(len(data)))
	if err != nil {
		return err
	}
	return Unzip(r, dest)
}

func UnzipFromFile(src string, dest string) error {
	r, err := zip.OpenReader(src)
	if err != nil {
		return err
	}

	defer func() {
		if err := r.Close(); err != nil {
			panic(err)
		}
	}()

	return Unzip(&r.Reader, dest)
}

func Unzip(r *zip.Reader, dest string) error {
	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)

		if f.FileInfo().IsDir() {
			os.MkdirAll(path, f.Mode())
		} else {
			// We have seen zips created with files in directories that were not previously specified in the zip file.
			// Even by well known zip creating products.
			os.MkdirAll(filepath.Dir(path), 0775)

			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
}