Add unit tests for manifest package

Signed-off-by: Stephen J Day <stephen.day@docker.com>

manifest/manifest_test.go

@@ -0,0 +1,110 @@
+package manifest
+
+import (
+	"bytes"
+	"encoding/json"
+	"reflect"
+	"testing"
+
+	"github.com/docker/libtrust"
+)
+
+type testEnv struct {
+	name, tag string
+	manifest  *Manifest
+	signed    *SignedManifest
+	pk        libtrust.PrivateKey
+}
+
+func TestManifestMarshaling(t *testing.T) {
+	env := genEnv(t)
+
+	// Check that the Raw field is the same as json.MarshalIndent with these
+	// parameters.
+	p, err := json.MarshalIndent(env.signed, "", "   ")
+	if err != nil {
+		t.Fatalf("error marshaling manifest: %v", err)
+	}
+
+	if !bytes.Equal(p, env.signed.Raw) {
+		t.Fatalf("manifest bytes not equal: %q != %q", string(env.signed.Raw), string(p))
+	}
+}
+
+func TestManifestUnmarshaling(t *testing.T) {
+	env := genEnv(t)
+
+	var signed SignedManifest
+	if err := json.Unmarshal(env.signed.Raw, &signed); err != nil {
+		t.Fatalf("error unmarshaling signed manifest: %v", err)
+	}
+
+	if !reflect.DeepEqual(&signed, env.signed) {
+		t.Fatalf("manifests are different after unmarshaling: %v != %v", signed, env.signed)
+	}
+}
+
+func TestManifestVerification(t *testing.T) {
+	env := genEnv(t)
+
+	publicKeys, err := env.signed.Verify()
+	if err != nil {
+		t.Fatalf("error verifying manifest: %v", err)
+	}
+
+	if len(publicKeys) == 0 {
+		t.Fatalf("no public keys found in signature")
+	}
+
+	var found bool
+	publicKey := env.pk.PublicKey()
+	// ensure that one of the extracted public keys matches the private key.
+	for _, candidate := range publicKeys {
+		if candidate.KeyID() == publicKey.KeyID() {
+			found = true
+			break
+		}
+	}
+
+	if !found {
+		t.Fatalf("expected public key, %v, not found in verified keys: %v", publicKey, publicKeys)
+	}
+}
+
+func genEnv(t *testing.T) *testEnv {
+	pk, err := libtrust.GenerateECP256PrivateKey()
+	if err != nil {
+		t.Fatalf("error generating test key: %v", err)
+	}
+
+	name, tag := "foo/bar", "test"
+
+	m := Manifest{
+		Versioned: Versioned{
+			SchemaVersion: 1,
+		},
+		Name: name,
+		Tag:  tag,
+		FSLayers: []FSLayer{
+			{
+				BlobSum: "asdf",
+			},
+			{
+				BlobSum: "qwer",
+			},
+		},
+	}
+
+	sm, err := m.Sign(pk)
+	if err != nil {
+		t.Fatalf("error signing manifest: %v", err)
+	}
+
+	return &testEnv{
+		name:     name,
+		tag:      tag,
+		manifest: &m,
+		signed:   sm,
+		pk:       pk,
+	}
+}