hack: add oci-pin tool

This tool can generate Go source files and lockfiles for container images.

hack/oci-pin/internal/extract/extract_test.go

@@ -0,0 +1,116 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package extract
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestDigest(t *testing.T) {
+	testCases := map[string]struct {
+		ociIndex   string
+		wantDigest string
+		wantErr    bool
+	}{
+		"valid OCI index": {
+			ociIndex:   validOCIIndex,
+			wantDigest: "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+			wantErr:    false,
+		},
+		"wrong version": {
+			ociIndex: `{
+				"schemaVersion": 1,
+				"mediaType": "application/vnd.oci.image.index.v1+json",
+				"manifests": [
+					{
+						"mediaType": "application/vnd.oci.image.manifest.v1+json",
+						"digest": "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+						"size": 0
+					}
+				]
+			}`,
+			wantErr: true,
+		},
+		"wrong media type": {
+			ociIndex: `{
+				"schemaVersion": 2,
+				"mediaType": "application/something-else",
+				"manifests": [
+					{
+						"mediaType": "application/vnd.oci.image.manifest.v1+json",
+						"digest": "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+						"size": 0
+					}
+				]
+			}`,
+			wantErr: true,
+		},
+		"incorrect manifest length": {
+			ociIndex: `{
+				"schemaVersion": 2,
+				"mediaType": "application/vnd.oci.image.index.v1+json",
+				"manifests": []
+			}`,
+			wantErr: true,
+		},
+		"incorrect manifest digest format": {
+			ociIndex: `{
+				"schemaVersion": 2,
+				"mediaType": "application/vnd.oci.image.index.v1+json",
+				"manifests": [
+					{
+						"mediaType": "application/vnd.oci.image.manifest.v1+json",
+						"digest": "foo:bar",
+						"size": 0
+					}
+				]
+			}`,
+			wantErr: true,
+		},
+		"malformed json": {
+			ociIndex: `}`,
+			wantErr:  true,
+		},
+	}
+
+	for name, tc := range testCases {
+		t.Run(name, func(t *testing.T) {
+			assert := assert.New(t)
+			require := require.New(t)
+			digest, err := Digest(bytes.NewBufferString(tc.ociIndex))
+			if tc.wantErr {
+				require.Error(err)
+				return
+			}
+			require.NoError(err)
+			assert.Equal(tc.wantDigest, digest)
+		})
+	}
+}
+
+const (
+	// This is a valid OCI index.
+	// It has a schema version of 2, a media type of
+	// "application/vnd.oci.image.index.v1+json", and a single manifest.
+	// The manifest has a media type of
+	// "application/vnd.oci.image.manifest.v1+json", and a digest.
+	// The digest is a valid SHA256 hash.
+	validOCIIndex = `{
+		"schemaVersion": 2,
+		"mediaType": "application/vnd.oci.image.index.v1+json",
+		"manifests": [
+			{
+				"mediaType": "application/vnd.oci.image.manifest.v1+json",
+				"digest": "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+				"size": 0
+			}
+		]
+	}`
+)