Ensure tar stream completes

pkg/build/strategies/sti/sti.go

@@ -6,6 +6,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"strings"
+	"sync"
 
 	"github.com/golang/glog"
 	"github.com/openshift/source-to-image/pkg/api"
@@ -407,6 +408,8 @@ func (b *STI) Execute(command string, config *api.Config) error {
 	}
 
 	if !config.LayeredBuild {
+		wg := sync.WaitGroup{}
+		wg.Add(1)
 		uploadDir := filepath.Join(config.WorkingDir, "upload")
 
 		// TODO: be able to pass a stream directly to the Docker build to avoid the double temp hit
@@ -418,11 +421,13 @@ func (b *STI) Execute(command string, config *api.Config) error {
 				if r := recover(); r != nil {
 					glog.Errorf("recovered panic: %#v", r)
 				}
+				wg.Done()
 			}()
 			err = b.tar.CreateTarStream(uploadDir, false, w)
 		}()
 
 		opts.Stdin = r
+		defer wg.Wait()
 	}
 
 	go func(reader io.Reader) {

pkg/tar/tar.go

@@ -88,6 +88,7 @@ func (t *stiTar) shouldExclude(path string) bool {
 // CreateTarStream creates a tar stream on the given writer from
 // the given directory while excluding files that match the given
 // exclusion pattern.
+// TODO: this should encapsulate the goroutine that generates the stream.
 func (t *stiTar) CreateTarStream(dir string, includeDirInPath bool, writer io.Writer) error {
 	tarWriter := tar.NewWriter(writer)
 	defer tarWriter.Close()