feat: xz compression (#1422)

* feat: xz compression

* remove .xz feature

* fix: format code with gofmt

* use larger dict for better compression

* Update pkg/archive/tarxz/tarxz.go

Co-authored-by: Carlos Alexandro Becker <caarlos0@users.noreply.github.com>

go.mod

@@ -19,6 +19,7 @@ require (
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/pkg/errors v0.9.1
 	github.com/stretchr/testify v1.5.1
+	github.com/ulikunitz/xz v0.5.6
 	github.com/xanzy/go-gitlab v0.29.0
 	gocloud.dev v0.19.0
 	golang.org/x/net v0.0.0-20200114155413-6afb5195e5aa // indirect

pkg/archive/archive.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/goreleaser/goreleaser/pkg/archive/gzip"
 	"github.com/goreleaser/goreleaser/pkg/archive/targz"
+	"github.com/goreleaser/goreleaser/pkg/archive/tarxz"
 	"github.com/goreleaser/goreleaser/pkg/archive/zip"
 )
 
@@ -24,6 +25,9 @@ func New(file *os.File) Archive {
 	if strings.HasSuffix(file.Name(), ".gz") {
 		return gzip.New(file)
 	}
+	if strings.HasSuffix(file.Name(), ".tar.xz") {
+		return tarxz.New(file)
+	}
 	if strings.HasSuffix(file.Name(), ".zip") {
 		return zip.New(file)
 	}

pkg/archive/archive_test.go

@@ -16,7 +16,7 @@ func TestArchive(t *testing.T) {
 	assert.NoError(err)
 	assert.NoError(os.Mkdir(folder+"/folder-inside", 0755))
 
-	for _, format := range []string{"tar.gz", "zip", "gz", "willbeatargzanyway"} {
+	for _, format := range []string{"tar.gz", "zip", "gz", "tar.xz", "willbeatargzanyway"} {
 		format := format
 		t.Run(format, func(t *testing.T) {
 			var archive = newArchive(folder, format, t)

pkg/archive/tarxz/tarxz.go

@@ -0,0 +1,61 @@
+// Package tarxz implements the Archive interface providing tar.xz archiving
+// and compression.
+package tarxz
+
+import (
+	"archive/tar"
+	"io"
+	"os"
+
+	"github.com/ulikunitz/xz"
+)
+
+// Archive as tar.xz
+type Archive struct {
+	xzw *xz.Writer
+	tw  *tar.Writer
+}
+
+// Close all closeables
+func (a Archive) Close() error {
+	if err := a.tw.Close(); err != nil {
+		return err
+	}
+	return a.xzw.Close()
+}
+
+// New tar.xz archive
+func New(target io.Writer) Archive {
+	xzw, _ := xz.WriterConfig{DictCap: 16 * 1024 * 1024}.NewWriter(target)
+	tw := tar.NewWriter(xzw)
+	return Archive{
+		xzw: xzw,
+		tw:  tw,
+	}
+}
+
+// Add file to the archive
+func (a Archive) Add(name, path string) error {
+	file, err := os.Open(path) // #nosec
+	if err != nil {
+		return err
+	}
+	defer file.Close() // nolint: errcheck
+	info, err := file.Stat()
+	if err != nil {
+		return err
+	}
+	header, err := tar.FileInfoHeader(info, name)
+	if err != nil {
+		return err
+	}
+	header.Name = name
+	if err = a.tw.WriteHeader(header); err != nil {
+		return err
+	}
+	if info.IsDir() {
+		return nil
+	}
+	_, err = io.Copy(a.tw, file)
+	return err
+}

pkg/archive/tarxz/tarxz_test.go

@@ -0,0 +1,72 @@
+package tarxz
+
+import (
+	"archive/tar"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/ulikunitz/xz"
+)
+
+func TestTarXzFile(t *testing.T) {
+	var assert = assert.New(t)
+	tmp, err := ioutil.TempDir("", "")
+	assert.NoError(err)
+	f, err := os.Create(filepath.Join(tmp, "test.tar.xz"))
+	assert.NoError(err)
+	defer f.Close() // nolint: errcheck
+	archive := New(f)
+
+	assert.Error(archive.Add("nope.txt", "../testdata/nope.txt"))
+	assert.NoError(archive.Add("foo.txt", "../testdata/foo.txt"))
+	assert.NoError(archive.Add("sub1", "../testdata/sub1"))
+	assert.NoError(archive.Add("sub1/bar.txt", "../testdata/sub1/bar.txt"))
+	assert.NoError(archive.Add("sub1/executable", "../testdata/sub1/executable"))
+	assert.NoError(archive.Add("sub1/sub2", "../testdata/sub1/sub2"))
+	assert.NoError(archive.Add("sub1/sub2/subfoo.txt", "../testdata/sub1/sub2/subfoo.txt"))
+
+	assert.NoError(archive.Close())
+	assert.Error(archive.Add("tar.go", "tar.go"))
+	assert.NoError(f.Close())
+
+	t.Log(f.Name())
+	f, err = os.Open(f.Name())
+	assert.NoError(err)
+	defer f.Close() // nolint: errcheck
+
+	info, err := f.Stat()
+	assert.NoError(err)
+	assert.Truef(info.Size() < 500, "archived file should be smaller than %d", info.Size())
+
+	xzf, err := xz.NewReader(f)
+	assert.NoError(err)
+	//defer xzf.Close() // nolint: errcheck
+
+	var paths []string
+	r := tar.NewReader(xzf)
+	for {
+		next, err := r.Next()
+		if err == io.EOF {
+			break
+		}
+		assert.NoError(err)
+		paths = append(paths, next.Name)
+		t.Logf("%s: %v", next.Name, next.FileInfo().Mode())
+		if next.Name == "sub1/executable" {
+			var ex = next.FileInfo().Mode() | 0111
+			assert.Equal(next.FileInfo().Mode().String(), ex.String())
+		}
+	}
+	assert.Equal([]string{
+		"foo.txt",
+		"sub1",
+		"sub1/bar.txt",
+		"sub1/executable",
+		"sub1/sub2",
+		"sub1/sub2/subfoo.txt",
+	}, paths)
+}