schema: add a docker v2.2 backwards compat test

schema/manifest_backwards_compatibility_test.go

@@ -0,0 +1,106 @@
+// Copyright 2016 The Linux Foundation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package schema_test
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/opencontainers/image-spec/schema"
+)
+
+var compatMap = map[string]string{
+	"application/vnd.docker.distribution.manifest.list.v2+json": "application/vnd.oci.image.manifest.list.v1+json",
+	"application/vnd.docker.distribution.manifest.v2+json":      "application/vnd.oci.image.manifest.v1+json",
+	"application/vnd.docker.image.rootfs.diff.tar.gzip":         "application/vnd.oci.image.rootfs.tar.gzip",
+	"application/vnd.docker.container.image.v1+json":            "application/vnd.oci.image.serialization.config.v1+json",
+}
+
+// convertFormats converts Docker v2.2 image format JSON documents to OCI
+// format by simply replacing instances of the strings found in the compatMap
+// found in the input string.
+func convertFormats(input string) string {
+	out := input
+	for k, v := range compatMap {
+		out = strings.Replace(out, v, k, -1)
+	}
+	return out
+}
+
+func TestBackwardsCompatibilityManifest(t *testing.T) {
+	for i, tt := range []struct {
+		manifest string
+		digest   string
+		fail     bool
+	}{
+		// manifest pulled from docker hub using hash value
+		//
+		// curl -L -H "Authorization: Bearer ..." -H \
+		// "Accept: application/vnd.docker.distribution.manifest.v2+json" \
+		// https://registry-1.docker.io/v2/library/docker/manifests/sha256:888206c77cd2811ec47e752ba291e5b7734e3ef137dfd222daadaca39a9f17bc
+		{
+			digest: "sha256:888206c77cd2811ec47e752ba291e5b7734e3ef137dfd222daadaca39a9f17bc",
+			manifest: `{
+   "schemaVersion": 2,
+   "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+   "config": {
+      "mediaType": "application/octet-stream",
+      "size": 3210,
+      "digest": "sha256:5359a4f250650c20227055957e353e8f8a74152f35fe36f00b6b1f9fc19c8861"
+   },
+   "layers": [
+      {
+         "mediaType": "application/vnd.docker.image.rootfs.diff.tar.gzip",
+         "size": 2310272,
+         "digest": "sha256:fae91920dcd4542f97c9350b3157139a5d901362c2abec284de5ebd1b45b4957"
+      },
+      {
+         "mediaType": "application/vnd.docker.image.rootfs.diff.tar.gzip",
+         "size": 913022,
+         "digest": "sha256:f384f6ab36adad485192f09379c0b58dc612a3cde82c551e082a7c29a87c95da"
+      },
+      {
+         "mediaType": "application/vnd.docker.image.rootfs.diff.tar.gzip",
+         "size": 9861668,
+         "digest": "sha256:ed0d2dd5e1a0e5e650a330a864c8a122e9aa91fa6ba9ac6f0bd1882e59df55e7"
+      },
+      {
+         "mediaType": "application/vnd.docker.image.rootfs.diff.tar.gzip",
+         "size": 465,
+         "digest": "sha256:ec4d00b58417c45f7ddcfde7bcad8c9d62a7d6d5d17cdc1f7d79bcb2e22c1491"
+      }
+   ]
+}`,
+			fail: false,
+		},
+	} {
+		sum := sha256.Sum256([]byte(tt.manifest))
+		got := fmt.Sprintf("sha256:%s", hex.EncodeToString(sum[:]))
+		if tt.digest != got {
+			t.Errorf("test %d: expected digest %s but got %s", i, tt.digest, got)
+		}
+
+		manifest := convertFormats(tt.manifest)
+		r := strings.NewReader(manifest)
+		err := schema.MediaTypeManifest.Validate(r)
+
+		if got := err != nil; tt.fail != got {
+			t.Errorf("test %d: expected validation failure %t but got %t, err %v", i, tt.fail, got, err)
+		}
+	}
+}