2 files changed, 106 insertions, 0 deletions
diff --git a/libpod/image/image.go b/libpod/image/image.go
index 633a682cc..b6e15e361 100644
--- a/libpod/image/image.go
+++ b/libpod/image/image.go
@@ -685,3 +685,60 @@ func Import(path, reference string, writer io.Writer, signingOptions SigningOpti
 	}
 	return runtime.NewFromLocal(reference)
 }
+
+// MatchRepoTag takes a string and tries to match it against an
+// image's repotags
+func (i *Image) MatchRepoTag(input string) (string, error) {
+	results := make(map[int][]string)
+	var maxCount int
+	// first check if we have an exact match with the input
+	if util.StringInSlice(input, i.Names()) {
+		return input, nil
+	}
+	// next check if we are missing the tag
+	dcImage, err := decompose(input)
+	if err != nil {
+		return "", err
+	}
+	for _, repoName := range i.Names() {
+		count := 0
+		dcRepoName, err := decompose(repoName)
+		if err != nil {
+			return "", err
+		}
+		if dcRepoName.registry == dcImage.registry && dcImage.registry != "" {
+			count++
+		}
+		if dcRepoName.name == dcImage.name && dcImage.name != "" {
+			count++
+		} else if splitString(dcRepoName.name) == splitString(dcImage.name) {
+			count++
+		}
+		if dcRepoName.tag == dcImage.tag {
+			count++
+		}
+		results[count] = append(results[count], repoName)
+		if count > maxCount {
+			maxCount = count
+		}
+	}
+	if maxCount == 0 {
+		return "", errors.Errorf("unable to match user input to any specific repotag")
+	}
+	if len(results[maxCount]) > 1 {
+		return "", errors.Errorf("user input matched multiple repotags for the image")
+	}
+	return results[maxCount][0], nil
+}
+
+// splitString splits input string by / and returns the last array item
+func splitString(input string) string {
+	split := strings.Split(input, "/")
+	return split[len(split)-1]
+}
+
+// InputIsID returns a bool if the user input for an image
+// is the image's partial or full id
+func (i *Image) InputIsID() bool {
+	return strings.HasPrefix(i.ID(), i.InputName)
+}
diff --git a/libpod/image/image_test.go b/libpod/image/image_test.go
index d9e8987a6..5c7cc191d 100644
--- a/libpod/image/image_test.go
+++ b/libpod/image/image_test.go
@@ -136,3 +136,52 @@ func TestImage_New(t *testing.T) {
 	// Shutdown the runtime and remove the temporary storage
 	cleanup(workdir, ir)
 }
+
+// TestImage_MatchRepoTag tests the various inputs we need to match
+// against an image's reponames
+func TestImage_MatchRepoTag(t *testing.T) {
+	//Set up
+	workdir, err := mkWorkDir()
+	assert.NoError(t, err)
+
+	so := storage.StoreOptions{
+		RunRoot:   workdir,
+		GraphRoot: workdir,
+	}
+	ir, err := NewImageRuntimeFromOptions(so)
+	assert.NoError(t, err)
+	newImage, err := ir.New("busybox", "", "", os.Stdout, nil, SigningOptions{})
+	assert.NoError(t, err)
+	err = newImage.TagImage("foo:latest")
+	assert.NoError(t, err)
+	err = newImage.TagImage("foo:bar")
+	assert.NoError(t, err)
+
+	// Tests start here.
+	for _, name := range bbNames {
+		repoTag, err := newImage.MatchRepoTag(name)
+		assert.NoError(t, err)
+		assert.Equal(t, "docker.io/library/busybox:latest", repoTag)
+	}
+
+	// Test against tagged images of busybox
+	// foo should resolve to foo:latest
+	repoTag, err := newImage.MatchRepoTag("foo")
+	assert.NoError(t, err)
+	assert.Equal(t, "foo:latest", repoTag)
+
+	// foo:bar should resolve to foo:bar
+	repoTag, err = newImage.MatchRepoTag("foo:bar")
+	assert.NoError(t, err)
+	assert.Equal(t, "foo:bar", repoTag)
+	// Shutdown the runtime and remove the temporary storage
+	cleanup(workdir, ir)
+}
+
+// Test_splitString tests the splitString function in image that
+// takes input and splits on / and returns the last array item
+func Test_splitString(t *testing.T) {
+	assert.Equal(t, splitString("foo/bar"), "bar")
+	assert.Equal(t, splitString("a/foo/bar"), "bar")
+	assert.Equal(t, splitString("bar"), "bar")
+}