Implement the Compress interface for Xz (#157)

* Implement the Compress interface for XZ

* Fix the logic of finding a target file from xz

* Move a common funtion extraFile to types.go

Co-authored-by: rick <[email protected]>

Author: amoghrajesh

go.mod

@@ -15,5 +15,6 @@ require (
 	github.com/onsi/gomega v1.16.0
 	github.com/spf13/cobra v1.2.1
 	github.com/stretchr/testify v1.7.0
+	github.com/xi2/xz v0.0.0-20171230120015-48954b6210f8
 	gopkg.in/yaml.v2 v2.4.0
 )

go.sum

@@ -416,6 +416,8 @@ github.com/ugorji/go v1.1.4/go.mod h1:uQMGLiO92mf5W77hV/PUCpI3pbzQx3CRekS0kk+RGr
 github.com/xanzy/ssh-agent v0.2.1/go.mod h1:mLlQY/MoOhWBj+gOGMQkOeiEvkx+8pJSI+0Bx9h2kr4=
 github.com/xanzy/ssh-agent v0.3.0 h1:wUMzuKtKilRgBAD1sUb8gOwwRr2FGoBVumcjoOACClI=
 github.com/xanzy/ssh-agent v0.3.0/go.mod h1:3s9xbODqPuuhK9JV1R321M/FlMZSBvE5aY6eAcqrDh0=
+github.com/xi2/xz v0.0.0-20171230120015-48954b6210f8 h1:nIPpBwaJSVYIxUFsDv3M8ofmx9yWTog9BfvIu0q41lo=
+github.com/xi2/xz v0.0.0-20171230120015-48954b6210f8/go.mod h1:HUYIGzjTL3rfEspMxjDjgmT5uz5wzYJKVo23qUhYTos=
 github.com/xiang90/probing v0.0.0-20190116061207-43a291ad63a2/go.mod h1:UETIi67q53MR2AWcXfiuqkDkRtnGDLqkBTpCHuJHxtU=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
 github.com/yuin/goldmark v1.1.25/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=

pkg/compress/gzip.go

@@ -7,11 +7,9 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"path/filepath"
-	"strings"
 )
 
-// GZip implements a compress which based gzip
+// GZip implements a compress which based is based on gzip
 type GZip struct {
 	additionBinaries []string
 }
@@ -75,23 +73,7 @@ func (c *GZip) ExtractFiles(sourceFile, targetName string) (err error) {
 	}
 
 	if err == nil && !found {
-		err = fmt.Errorf("cannot found item '%s' from '%s'", targetName, sourceFile)
+		err = fmt.Errorf("cannot find item '%s' from '%s'", targetName, sourceFile)
 	}
 	return
 }
-
-func extraFile(name, targetName, tarFile string, header *tar.Header, tarReader *tar.Reader) (err error) {
-	if name != targetName && !strings.HasSuffix(name, "/"+targetName) {
-		return
-	}
-	var targetFile *os.File
-	if targetFile, err = os.OpenFile(fmt.Sprintf("%s/%s", filepath.Dir(tarFile), targetName),
-		os.O_CREATE|os.O_RDWR, os.FileMode(header.Mode)); err != nil {
-		return
-	}
-	if _, err = io.Copy(targetFile, tarReader); err != nil {
-		return
-	}
-	_ = targetFile.Close()
-	return
-}

pkg/compress/interface.go

@@ -0,0 +1,31 @@
+package compress
+
+import (
+	"archive/tar"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// Compress is a common compress interface
+type Compress interface {
+	ExtractFiles(sourceFile, targetName string) error
+}
+
+func extraFile(name, targetName, tarFile string, header *tar.Header, tarReader *tar.Reader) (err error) {
+	if name != targetName && !strings.HasSuffix(name, "/"+targetName) {
+		return
+	}
+	var targetFile *os.File
+	if targetFile, err = os.OpenFile(fmt.Sprintf("%s/%s", filepath.Dir(tarFile), targetName),
+		os.O_CREATE|os.O_RDWR, os.FileMode(header.Mode)); err != nil {
+		return
+	}
+	if _, err = io.Copy(targetFile, tarReader); err != nil {
+		return
+	}
+	_ = targetFile.Close()
+	return
+}

pkg/compress/types.go

@@ -1,3 +1,79 @@
 package compress
 
-// TODO implement extract files, for instance, you can use https://github.com/ulikunitz/xz
+import (
+	"archive/tar"
+	"errors"
+	"fmt"
+	"github.com/xi2/xz"
+	"io"
+	"log"
+	"os"
+)
+
+// Xz implements a compress which based is based on xz
+type Xz struct {
+	additionBinaries []string
+}
+
+// NewXz creates an instance of Xz
+func NewXz(additionBinaries []string) *Xz {
+	return &Xz{additionBinaries: additionBinaries}
+}
+
+// ExtractFiles extracts files from a target compress file
+func (x *Xz) ExtractFiles(sourceFile, targetName string) (err error) {
+	if targetName == "" {
+		err = errors.New("target filename is empty")
+		return
+	}
+	var f *os.File
+	if f, err = os.Open(sourceFile); err != nil {
+		return err
+	}
+	defer func() {
+		_ = f.Close()
+	}()
+
+	// Create a xz Reader
+	r, err := xz.NewReader(f, 0)
+	if err != nil {
+		log.Fatal(err)
+		return
+	}
+
+	var header *tar.Header
+	var found bool
+	// Create a tar Reader
+	tarReader := tar.NewReader(r)
+	for {
+		if header, err = tarReader.Next(); err == io.EOF {
+			err = nil
+			break
+		}
+		if err != nil {
+			log.Fatal(err)
+			return
+		}
+		name := header.Name
+
+		switch header.Typeflag {
+		case tar.TypeReg:
+			if err = extraFile(name, targetName, sourceFile, header, tarReader); err == nil {
+				found = true
+			} else {
+				break
+			}
+
+			for i := range x.additionBinaries {
+				addition := x.additionBinaries[i]
+				if err = extraFile(addition, addition, sourceFile, header, tarReader); err != nil {
+					return
+				}
+			}
+		}
+	}
+	if err == nil && !found {
+		err = fmt.Errorf("cannot find item '%s' from '%s'", targetName, sourceFile)
+	}
+	return
+}

pkg/compress/xz.go

@@ -113,8 +113,14 @@ func (o *Installer) OverWriteBinary(sourceFile, targetPath string) (err error) {
 }
 
 func (o *Installer) extractFiles(tarFile, targetName string) (err error) {
-	// TODO choose a correct compress instance
-	compressor := compress.NewGZip(o.AdditionBinaries)
+	// Select the right decompressor based on file type
+	extension := path.Ext(tarFile)
+	var compressor compress.Compress
+	if extension == ".xz" {
+		compressor = compress.NewXz(o.AdditionBinaries)
+	} else {
+		compressor = compress.NewGZip(o.AdditionBinaries)
+	}
 	err = compressor.ExtractFiles(tarFile, targetName)
 	return
 }