diff --git a/daemon/mgr/image_test.go b/daemon/mgr/image_test.go
index 1467b424d..de56b39dd 100644
--- a/daemon/mgr/image_test.go
+++ b/daemon/mgr/image_test.go
@@ -4,42 +4,51 @@ import (
 	"testing"
 
 	"github.com/alibaba/pouch/apis/types"
+	"strings"
 )
 
-func TestImageCache(t *testing.T) {
-	images := []types.ImageInfo{
-		{
-			RepoDigests: []string{"docker.io/library/nginx@sha256:dc5f67a48da730d67bf4bfb8824ea8a51be26711de090d6d5a1ffff2723168a3"},
-			RepoTags:    []string{"docker.io/library/nginx:alpine"},
-			ID:          "sha256:dc5f67a48da730d67bf4bfb8824ea8a51be26711de090d6d5a1ffff2723168a3",
-		},
-		{
-			RepoDigests: []string{"reg.docker.alibaba-inc.com/base/hello-world@sha256:2075ac87b043415d35bb6351b4a59df19b8ad154e578f7048335feeb02d0f759"},
-			RepoTags:    []string{"reg.docker.alibaba-inc.com/base/hello-world:latest"},
-			ID:          "sha256:2075ac87b043415d35bb6351b4a59df19b8ad154e578f7048335feeb02d0f759",
-		},
-		{
-			RepoDigests: []string{"reg.docker.alibaba-inc.com/base/hello-world@sha256:ded83fbb30d5fad804784215bc454c3844653cb0a907a512d44e25429507e415s"},
-			RepoTags:    []string{"reg.docker.alibaba-inc.com/busybox:latest"},
-			ID:          "sha256:ded83fbb30d5fad804784215bc454c3844653cb0a907a512d44e25429507e415s",
-		},
-		{
-			RepoDigests: []string{"reg.docker.alibaba-inc.com/base/hello-world@sha256:6591a3cb89fec995f299fa52c65e56aa33c779fd965060cf3b7759cd4b346aac"},
-			RepoTags:    []string{"reg.docker.alibaba-inc.com/fedora:21"},
-			ID:          "sha256:6591a3cb89fec995f299fa52c65e56aa33c779fd965060cf3b7759cd4b346aac",
-		},
-		{
-			RepoDigests: []string{"reg.docker.alibaba-inc.com/base/hello-world@sha256:03b17f82af79a338571410df9b26670c160175eda81d6e9fd62e3fda6b728928"},
-			RepoTags:    []string{"reg.docker.alibaba-inc.com/mysql:5.6.23"},
-			ID:          "sha256:03b17f82af79a338571410df9b26670c160175eda81d6e9fd62e3fda6b728928",
-		},
-	}
+var defaultImageInfos = []types.ImageInfo{
+	{
+		RepoDigests: []string{"docker.io/library/nginx@sha256:dc5f67a48da730d67bf4bfb8824ea8a51be26711de090d6d5a1ffff2723168a3"},
+		RepoTags:    []string{"docker.io/library/nginx:alpine"},
+		ID:          "sha256:dc5f67a48da730d67bf4bfb8824ea8a51be26711de090d6d5a1ffff2723168a3",
+	},
+	{
+		RepoDigests: []string{"reg.docker.alibaba-inc.com/base/hello-world@sha256:2075ac87b043415d35bb6351b4a59df19b8ad154e578f7048335feeb02d0f759"},
+		RepoTags:    []string{"reg.docker.alibaba-inc.com/base/hello-world:latest"},
+		ID:          "sha256:2075ac87b043415d35bb6351b4a59df19b8ad154e578f7048335feeb02d0f759",
+	},
+	{
+		RepoDigests: []string{"reg.docker.alibaba-inc.com/base/hello-world@sha256:ded83fbb30d5fad804784215bc454c3844653cb0a907a512d44e25429507e415s"},
+		RepoTags:    []string{"reg.docker.alibaba-inc.com/busybox:latest"},
+		ID:          "sha256:ded83fbb30d5fad804784215bc454c3844653cb0a907a512d44e25429507e415s",
+	},
+	{
+		RepoDigests: []string{"reg.docker.alibaba-inc.com/base/hello-world@sha256:6591a3cb89fec995f299fa52c65e56aa33c779fd965060cf3b7759cd4b346aac"},
+		RepoTags:    []string{"reg.docker.alibaba-inc.com/fedora:21"},
+		ID:          "sha256:6591a3cb89fec995f299fa52c65e56aa33c779fd965060cf3b7759cd4b346aac",
+	},
+	{
+		RepoDigests: []string{"reg.docker.alibaba-inc.com/base/hello-world@sha256:03b17f82af79a338571410df9b26670c160175eda81d6e9fd62e3fda6b728928"},
+		RepoTags:    []string{"reg.docker.alibaba-inc.com/mysql:5.6.23"},
+		ID:          "sha256:03b17f82af79a338571410df9b26670c160175eda81d6e9fd62e3fda6b728928",
+	},
+}
 
+func genImageCache(imageInfos []types.ImageInfo) *imageCache {
+	if len(imageInfos) == 0 {
+		imageInfos = defaultImageInfos
+	}
 	cache := newImageCache()
 
-	for i := range images {
-		cache.put(&images[i])
+	for i := range imageInfos {
+		cache.put(&imageInfos[i])
 	}
+	return cache
+}
+
+func TestImageCache(t *testing.T) {
+	cache := genImageCache([]types.ImageInfo{})
 
 	if i, err := cache.get("dc5f67a48da7"); err != nil {
 		t.Fatal(err)
@@ -72,3 +81,73 @@ func TestImageCache(t *testing.T) {
 		t.Errorf("remove failed: %s", i.RepoTags[0])
 	}
 }
+
+func TestImageCacheGet(t *testing.T) {
+	testCases := []struct {
+		idOrRef         string
+		expectedImageID string
+	}{
+		{
+			idOrRef:         defaultImageInfos[0].RepoTags[0],
+			expectedImageID: defaultImageInfos[0].ID,
+		},
+		{
+			idOrRef:         defaultImageInfos[1].RepoDigests[0],
+			expectedImageID: defaultImageInfos[1].ID,
+		},
+		{
+			idOrRef:         strings.Trim(defaultImageInfos[2].ID, "sha256:"),
+			expectedImageID: defaultImageInfos[2].ID,
+		},
+		{
+			idOrRef:         "reg.docker.alibaba-inc.com/base/hello-world",
+			expectedImageID: defaultImageInfos[1].ID,
+		},
+		{
+			idOrRef:         "dc5f67a48da730d67bf4",
+			expectedImageID: defaultImageInfos[0].ID,
+		},
+	}
+
+	cache := genImageCache([]types.ImageInfo{})
+	for _, testCase := range testCases {
+		if i, err := cache.get(testCase.idOrRef); err != nil {
+			t.Fatal(err)
+		} else if i.ID != testCase.expectedImageID {
+			t.Errorf("get error: expected: %s, but was: %s", testCase.expectedImageID, i.ID)
+		}
+	}
+}
+
+func TestImageCacheGetErrors(t *testing.T) {
+	errorCases := []struct {
+		idOrRef          string
+		expectedErrorMsg string
+	}{
+		{
+			idOrRef:          "fake_image",
+			expectedErrorMsg: "image: fake_image: not found",
+		},
+		{
+			idOrRef:          "b9c6c00334a2",
+			expectedErrorMsg: "image: b9c6c00334a2: not found",
+		},
+		{
+			idOrRef:          "registry.hub.docker.com/library/golang@sha256:b95921b1e0b7092e53473acede637b4ecc6ee2af54119cab1a674dba8c3a59da",
+			expectedErrorMsg: "image digest: registry.hub.docker.com/library/golang@sha256:b95921b1e0b7092e53473acede637b4ecc6ee2af54119cab1a674dba8c3a59da: not found",
+		},
+	}
+
+	cache := genImageCache([]types.ImageInfo{})
+
+	for _, errorCase := range errorCases {
+		if _, err := cache.get(errorCase.idOrRef); err == nil {
+			t.Errorf("get error: %s", errorCase.idOrRef)
+		} else if err.Error() != errorCase.expectedErrorMsg {
+			t.Errorf("get error: expected: %s, but was: %s",
+				errorCase.expectedErrorMsg,
+				err.Error(),
+			)
+		}
+	}
+}