1 files changed, 116 insertions, 0 deletions
diff --git a/src/orchestrator/utils/utils.go b/src/orchestrator/utils/utils.go
new file mode 100644
index 00000000..13c78ba4
--- /dev/null
+++ b/src/orchestrator/utils/utils.go
@@ -0,0 +1,116 @@
+/*
+ * Copyright 2020 Intel Corporation, Inc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package utils
+
+import (
+	"archive/tar"
+	"compress/gzip"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+	"path/filepath"
+
+	pkgerrors "github.com/pkg/errors"
+)
+
+//ExtractTarBall provides functionality to extract a tar.gz file
+//into a temporary location for later use.
+//It returns the path to the new location
+func ExtractTarBall(r io.Reader) (string, error) {
+	//Check if it is a valid gz
+	gzf, err := gzip.NewReader(r)
+	if err != nil {
+		return "", pkgerrors.Wrap(err, "Invalid gzip format")
+	}
+
+	//Check if it is a valid tar file
+	//Unfortunately this can only be done by inspecting all the tar contents
+	tarR := tar.NewReader(gzf)
+	first := true
+
+	outDir, _ := ioutil.TempDir("", "k8s-ext-")
+
+	for true {
+		header, err := tarR.Next()
+
+		if err == io.EOF {
+			//Check if we have just a gzip file without a tar archive inside
+			if first {
+				return "", pkgerrors.New("Empty or non-existant Tar file found")
+			}
+			//End of archive
+			break
+		}
+
+		if err != nil {
+			return "", pkgerrors.Wrap(err, "Error reading tar file")
+		}
+
+		target := filepath.Join(outDir, header.Name)
+
+		switch header.Typeflag {
+		case tar.TypeDir:
+			if _, err := os.Stat(target); err != nil {
+				// Using 755 read, write, execute for owner
+				// groups and others get read and execute permissions
+				// on the folder.
+				if err := os.MkdirAll(target, 0755); err != nil {
+					return "", pkgerrors.Wrap(err, "Creating directory")
+				}
+			}
+		case tar.TypeReg:
+			if target == outDir { // Handle '.' substituted to '' entry
+				continue
+			}
+
+			err = EnsureDirectory(target)
+			if err != nil {
+				return "", pkgerrors.Wrap(err, "Creating Directory")
+			}
+
+			f, err := os.OpenFile(target, os.O_CREATE|os.O_RDWR, os.FileMode(header.Mode))
+			if err != nil {
+				return "", pkgerrors.Wrap(err, "Creating file")
+			}
+
+			// copy over contents
+			if _, err := io.Copy(f, tarR); err != nil {
+				return "", pkgerrors.Wrap(err, "Copying file content")
+			}
+
+			// close for each file instead of a defer for all
+			// at the end of the function
+			f.Close()
+		}
+
+		first = false
+	}
+
+	return outDir, nil
+}
+
+//EnsureDirectory makes sure that the directories specified in the path exist
+//If not, it will create them, if possible.
+func EnsureDirectory(f string) error {
+	base := path.Dir(f)
+	_, err := os.Stat(base)
+	if err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	return os.MkdirAll(base, 0755)
+}