From 3e658d29a667dee19e4e35e578fd0274a7df221b Mon Sep 17 00:00:00 2001
From: Josh Hawn <josh.hawn@docker.com>
Date: Tue, 10 Mar 2015 14:40:58 -0700
Subject: [PATCH] digest: Minor refactoring

Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
---
 docs/handlers/api_test.go       |  5 ++++-
 docs/storage/filereader_test.go |  6 +++++-
 docs/storage/filewriter_test.go | 18 +++++++++++++++---
 docs/storage/layerupload.go     |  5 ++++-
 4 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/docs/handlers/api_test.go b/docs/handlers/api_test.go
index 22f2d9ca..ab8187c1 100644
--- a/docs/handlers/api_test.go
+++ b/docs/handlers/api_test.go
@@ -236,7 +236,10 @@ func TestLayerAPI(t *testing.T) {
 	})
 
 	// Verify the body
-	verifier := digest.NewDigestVerifier(layerDigest)
+	verifier, err := digest.NewDigestVerifier(layerDigest)
+	if err != nil {
+		t.Fatalf("unexpected error getting digest verifier: %s", err)
+	}
 	io.Copy(verifier, resp.Body)
 
 	if !verifier.Verified() {
diff --git a/docs/storage/filereader_test.go b/docs/storage/filereader_test.go
index 7c554e8b..8a077603 100644
--- a/docs/storage/filereader_test.go
+++ b/docs/storage/filereader_test.go
@@ -41,7 +41,11 @@ func TestSimpleRead(t *testing.T) {
 		t.Fatalf("error allocating file reader: %v", err)
 	}
 
-	verifier := digest.NewDigestVerifier(dgst)
+	verifier, err := digest.NewDigestVerifier(dgst)
+	if err != nil {
+		t.Fatalf("error getting digest verifier: %s", err)
+	}
+
 	io.Copy(verifier, fr)
 
 	if !verifier.Verified() {
diff --git a/docs/storage/filewriter_test.go b/docs/storage/filewriter_test.go
index 06db31f3..a8ea6241 100644
--- a/docs/storage/filewriter_test.go
+++ b/docs/storage/filewriter_test.go
@@ -55,7 +55,11 @@ func TestSimpleWrite(t *testing.T) {
 	}
 	defer fr.Close()
 
-	verifier := digest.NewDigestVerifier(dgst)
+	verifier, err := digest.NewDigestVerifier(dgst)
+	if err != nil {
+		t.Fatalf("unexpected error getting digest verifier: %s", err)
+	}
+
 	io.Copy(verifier, fr)
 
 	if !verifier.Verified() {
@@ -94,7 +98,11 @@ func TestSimpleWrite(t *testing.T) {
 	}
 	defer fr.Close()
 
-	verifier = digest.NewDigestVerifier(doubledgst)
+	verifier, err = digest.NewDigestVerifier(doubledgst)
+	if err != nil {
+		t.Fatalf("unexpected error getting digest verifier: %s", err)
+	}
+
 	io.Copy(verifier, fr)
 
 	if !verifier.Verified() {
@@ -141,7 +149,11 @@ func TestSimpleWrite(t *testing.T) {
 	}
 	defer fr.Close()
 
-	verifier = digest.NewDigestVerifier(doubledgst)
+	verifier, err = digest.NewDigestVerifier(doubledgst)
+	if err != nil {
+		t.Fatalf("unexpected error getting digest verifier: %s", err)
+	}
+
 	io.Copy(verifier, fr)
 
 	if !verifier.Verified() {
diff --git a/docs/storage/layerupload.go b/docs/storage/layerupload.go
index 69b547f5..fdb00e93 100644
--- a/docs/storage/layerupload.go
+++ b/docs/storage/layerupload.go
@@ -85,7 +85,10 @@ func (luc *layerUploadController) Cancel() error {
 // validateLayer checks the layer data against the digest, returning an error
 // if it does not match. The canonical digest is returned.
 func (luc *layerUploadController) validateLayer(dgst digest.Digest) (digest.Digest, error) {
-	digestVerifier := digest.NewDigestVerifier(dgst)
+	digestVerifier, err := digest.NewDigestVerifier(dgst)
+	if err != nil {
+		return "", err
+	}
 
 	// TODO(stevvooe): Store resumable hash calculations in upload directory
 	// in driver. Something like a file at path <uuid>/resumablehash/<offest>