Unarchive zip file after fetcher downloads the package (#301)

Fetcher now uncompresses archive files. 

This is triggered by automatically detecting the file format, although maybe we should make that explicit or at least move the detection into the client.

environments/fetcher/fetcher.go

@@ -4,6 +4,7 @@ import (
 	"crypto/sha256"
 	"encoding/hex"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -13,6 +14,8 @@ import (
 	"path/filepath"
 	"time"
 
+	"github.com/mholt/archiver"
+	"github.com/satori/go.uuid"
 	"k8s.io/client-go/1.5/kubernetes"
 	"k8s.io/client-go/1.5/pkg/api"
 
@@ -196,12 +199,24 @@ func (fetcher *Fetcher) Handler(w http.ResponseWriter, r *http.Request) {
 
 	}
 
+	// check file type here, if the file is a zip file unarchive it.
+	if archiver.Zip.Match(tmpPath) {
+		// unarchive tmp file to a tmp unarchive path
+		tmpUnarchivePath := filepath.Join(fetcher.sharedVolumePath, uuid.NewV4().String())
+		err = fetcher.unarchive(tmpPath, tmpUnarchivePath)
+		if err != nil {
+			log.Println(err.Error())
+			http.Error(w, err.Error(), 500)
+			return
+		}
+		tmpPath = tmpUnarchivePath
+	}
+
 	// move tmp file to requested filename
-	err = os.Rename(tmpPath, filepath.Join(fetcher.sharedVolumePath, req.Filename))
+	err = fetcher.rename(tmpPath, filepath.Join(fetcher.sharedVolumePath, req.Filename))
 	if err != nil {
-		e := fmt.Sprintf("Failed to move file: %v", err)
-		log.Printf(e)
-		http.Error(w, e, 500)
+		log.Println(err.Error())
+		http.Error(w, err.Error(), 500)
 		return
 	}
 
@@ -209,3 +224,25 @@ func (fetcher *Fetcher) Handler(w http.ResponseWriter, r *http.Request) {
 	// all done
 	w.WriteHeader(http.StatusOK)
 }
+
+func (fetcher *Fetcher) rename(src string, dst string) error {
+	err := os.Rename(src, dst)
+	if err != nil {
+		return errors.New(fmt.Sprintf("Failed to move file: %v", err))
+	}
+	return nil
+}
+
+// archive is a function that zips directory into a zip file
+func (fetcher *Fetcher) archive(src string, dst string) error {
+	return archiver.Zip.Make(dst, []string{src})
+}
+
+// unarchive is a function that unzips a zip file to destination
+func (fetcher *Fetcher) unarchive(src string, dst string) error {
+	err := archiver.Zip.Open(src, dst)
+	if err != nil {
+		return errors.New(fmt.Sprintf("Failed to unzip file: %v", err))
+	}
+	return nil
+}