Merge pull request #106 from cloudfoundry/fix-strip-components-impl

Fix behavior for StripComponents with leading ./
cloudfoundry · Dec 3, 2024 · 9b77f09 · 9b77f09
2 parents 3dc5178 + 145cfe0
commit 9b77f09
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Showing 2 changed files with 19 additions and 14 deletions.
diff --git a/fileutil/tarball_compressor.go b/fileutil/tarball_compressor.go
@@ -1,6 +1,7 @@
 package fileutil
 
 import (
+	"archive/tar"
 	"fmt"
 	"io"
 	"io/fs"
@@ -9,16 +10,16 @@ import (
 	"runtime"
 	"strings"
 
-	"archive/tar"
-
 	"github.com/klauspost/pgzip"
 
 	bosherr "github.com/cloudfoundry/bosh-utils/errors"
 	boshsys "github.com/cloudfoundry/bosh-utils/system"
 )
 
+const forwardSlash string = "/"
+
 type tarballCompressor struct {
-	fs        boshsys.FileSystem
+	fs boshsys.FileSystem
 }
 
 func NewTarballCompressor(
@@ -72,7 +73,7 @@ func (c tarballCompressor) CompressSpecificFilesInDir(dir string, files []string
 
 			header.Name = relPath
 			if runtime.GOOS == "windows" {
-				header.Name = strings.ReplaceAll(relPath, "\\", "/")
+				header.Name = strings.ReplaceAll(relPath, "\\", forwardSlash)
 			}
 
 			if err := tw.WriteHeader(header); err != nil {
@@ -98,7 +99,7 @@ func (c tarballCompressor) CompressSpecificFilesInDir(dir string, files []string
 		return "", bosherr.WrapError(err, "Creating tgz")
 	}
 
-        if err = tw.Close(); err != nil {
+	if err = tw.Close(); err != nil {
 		return "", bosherr.WrapError(err, "Closing tar writer")
 	}
 
@@ -140,13 +141,13 @@ func (c tarballCompressor) DecompressFileToDir(tarballPath string, dir string, o
 
 		if options.PathInArchive != "" && !strings.HasPrefix(
 			filepath.Clean(header.Name), filepath.Clean(options.PathInArchive)) {
-				continue
+			continue
 		}
 
 		fullName := filepath.Join(dir, filepath.FromSlash(header.Name))
 
 		if options.StripComponents > 0 {
-			components := strings.Split(filepath.Clean(header.Name), string(filepath.Separator))
+			components := strings.Split(header.Name, forwardSlash)
 			if len(components) <= options.StripComponents {
 				continue
 			}
@@ -171,12 +172,12 @@ func (c tarballCompressor) DecompressFileToDir(tarballPath string, dir string, o
 			}
 
 		case tar.TypeLink:
-                        if err := c.fs.Symlink(header.Linkname, fullName); err != nil {
+			if err := c.fs.Symlink(header.Linkname, fullName); err != nil {
 				return bosherr.WrapError(err, "Decompressing link")
 			}
 
-                case tar.TypeSymlink:
-                        if err := c.fs.Symlink(header.Linkname, fullName); err != nil {
+		case tar.TypeSymlink:
+			if err := c.fs.Symlink(header.Linkname, fullName); err != nil {
 				return bosherr.WrapError(err, "Decompressing symlink")
 			}
 

diff --git a/fileutil/tarball_compressor_test.go b/fileutil/tarball_compressor_test.go
@@ -161,7 +161,6 @@ var _ = Describe("tarballCompressor", func() {
 				"other_logs/more_logs/more.stdout.log",
 			))
 
-
 			content, err := fs.ReadFileString(filepath.FromSlash(dstDir + "/app.stdout.log"))
 			Expect(err).ToNot(HaveOccurred())
 			Expect(content).To(ContainSubstring("this is app stdout"))
@@ -250,7 +249,7 @@ var _ = Describe("tarballCompressor", func() {
 
 			var (
 				tarballPath string
-				fs *fakesys.FakeFileSystem
+				fs          *fakesys.FakeFileSystem
 			)
 
 			BeforeEach(func() {
@@ -267,7 +266,6 @@ var _ = Describe("tarballCompressor", func() {
 				Expect(err).ToNot(HaveOccurred())
 			})
 
-
 			It("uses no same owner option", func() {
 				compressor := NewTarballCompressor(fs)
 				err := compressor.DecompressFileToDir(tarballPath, dstDir, CompressorOptions{})
@@ -353,9 +351,15 @@ var _ = Describe("tarballCompressor", func() {
 			dstElements, err := pathsInDir(dstDir)
 			Expect(err).ToNot(HaveOccurred())
 
+			// tar --strip-components treats a leading `./` in the file headers as its own component.
+			// So ./dir/some-file becomes dir/some-file with strip-components = 1.
+			// The example tar file in this test contains the leading ./ for each of its files.
 			Expect(dstElements).To(Equal([]string{
 				"./",
-				"double-nested-file",
+				"empty-nested-dir/",
+				"nested-dir/",
+				"nested-dir/double-nested-file",
+				"nested-file",
 			}))
 		})
 	})