fixing up tests to work with for non-tarsum future

Signed-off-by: David Lawrence <david.lawrence@docker.com> (github: endophage)

digest/digest.go

@@ -16,6 +16,8 @@ import (
 const (
 	// DigestTarSumV1EmptyTar is the digest for the empty tar file.
 	DigestTarSumV1EmptyTar = "tarsum.v1+sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
+	// DigestSha256EmptyTar is the canonical sha256 digest of empty data
+	DigestSha256EmptyTar = "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
 )
 
 // Digest allows simple protection of hex formatted digest strings, prefixed

digest/digester.go

@@ -0,0 +1,44 @@
+package digest
+
+import (
+	"crypto/sha256"
+	"hash"
+)
+
+// Digester calculates the digest of written data. It is functionally
+// equivalent to hash.Hash but provides methods for returning the Digest type
+// rather than raw bytes.
+type Digester struct {
+	alg  string
+	hash hash.Hash
+}
+
+// NewDigester create a new Digester with the given hashing algorithm and instance
+// of that algo's hasher.
+func NewDigester(alg string, h hash.Hash) Digester {
+	return Digester{
+		alg:  alg,
+		hash: h,
+	}
+}
+
+// NewCanonicalDigester is a convenience function to create a new Digester with
+// out default settings.
+func NewCanonicalDigester() Digester {
+	return NewDigester("sha256", sha256.New())
+}
+
+// Write data to the digester. These writes cannot fail.
+func (d *Digester) Write(p []byte) (n int, err error) {
+	return d.hash.Write(p)
+}
+
+// Digest returns the current digest for this digester.
+func (d *Digester) Digest() Digest {
+	return NewDigest(d.alg, d.hash)
+}
+
+// Reset the state of the digester.
+func (d *Digester) Reset() {
+	d.hash.Reset()
+}

registry/handlers/api_test.go

@@ -573,7 +573,9 @@ func doPushLayer(t *testing.T, ub *v2.URLBuilder, name string, dgst digest.Diges
 
 // pushLayer pushes the layer content returning the url on success.
 func pushLayer(t *testing.T, ub *v2.URLBuilder, name string, dgst digest.Digest, uploadURLBase string, body io.Reader) string {
-	resp, err := doPushLayer(t, ub, name, dgst, uploadURLBase, body)
+	digester := digest.NewCanonicalDigester()
+
+	resp, err := doPushLayer(t, ub, name, dgst, uploadURLBase, io.TeeReader(body, &digester))
 	if err != nil {
 		t.Fatalf("unexpected error doing push layer request: %v", err)
 	}
@@ -581,7 +583,13 @@ func pushLayer(t *testing.T, ub *v2.URLBuilder, name string, dgst digest.Digest,
 
 	checkResponse(t, "putting monolithic chunk", resp, http.StatusCreated)
 
-	expectedLayerURL, err := ub.BuildBlobURL(name, dgst)
+	if err != nil {
+		t.Fatalf("error generating sha256 digest of body")
+	}
+
+	sha256Dgst := digester.Digest()
+
+	expectedLayerURL, err := ub.BuildBlobURL(name, sha256Dgst)
 	if err != nil {
 		t.Fatalf("error building expected layer url: %v", err)
 	}
@@ -589,7 +597,7 @@ func pushLayer(t *testing.T, ub *v2.URLBuilder, name string, dgst digest.Digest,
 	checkHeaders(t, resp, http.Header{
 		"Location":              []string{expectedLayerURL},
 		"Content-Length":        []string{"0"},
-		"Docker-Content-Digest": []string{dgst.String()},
+		"Docker-Content-Digest": []string{sha256Dgst.String()},
 	})
 
 	return resp.Header.Get("Location")
@@ -682,7 +690,7 @@ func checkHeaders(t *testing.T, resp *http.Response, headers http.Header) {
 
 			for _, hv := range resp.Header[k] {
 				if hv != v {
-					t.Fatalf("header value not matched in response: %q != %q", hv, v)
+					t.Fatalf("%v header value not matched in response: %q != %q", k, hv, v)
 				}
 			}
 		}

registry/storage/layer_test.go

@@ -266,12 +266,12 @@ func TestLayerUploadZeroLength(t *testing.T) {
 
 	io.Copy(upload, bytes.NewReader([]byte{}))
 
-	dgst, err := digest.FromTarArchive(bytes.NewReader([]byte{}))
+	dgst, err := digest.FromReader(bytes.NewReader([]byte{}))
 	if err != nil {
 		t.Fatalf("error getting zero digest: %v", err)
 	}
 
-	if dgst != digest.DigestTarSumV1EmptyTar {
+	if dgst != digest.DigestSha256EmptyTar {
 		// sanity check on zero digest
 		t.Fatalf("digest not as expected: %v != %v", dgst, digest.DigestTarSumV1EmptyTar)
 	}

registry/storage/layerupload.go

@@ -159,7 +159,7 @@ func (luc *layerUploadController) moveLayer(dgst digest.Digest) error {
 			// a zero-length blob into a nonzero-length blob location. To
 			// prevent this horrid thing, we employ the hack of only allowing
 			// to this happen for the zero tarsum.
-			if dgst == digest.DigestTarSumV1EmptyTar {
+			if dgst == digest.DigestSha256EmptyTar {
 				return luc.driver.PutContent(blobPath, []byte{})
 			}