Review of platform detection (#56)

* Leave default image platform empty for static provider (see FAQ doc)
* Handle platform variant
* Add database migration process
* Switch to Open Container Specification labels as label-schema.org ones are deprecated
* Remove unneeded `diun.os` and `diun.arch` docker labels

Co-authored-by: CrazyMax <crazy-max@users.noreply.github.com>

pkg/registry/manifest.go

@@ -1,6 +1,7 @@
 package registry
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/containers/image/v5/manifest"
@@ -16,9 +17,8 @@ type Manifest struct {
 	Created       *time.Time
 	DockerVersion string
 	Labels        map[string]string
-	Architecture  string
-	Os            string
 	Layers        []string
+	Platform      string `json:"-"`
 }
 
 // Manifest returns the manifest for a specific image
@@ -26,18 +26,18 @@ func (c *Client) Manifest(image Image) (Manifest, error) {
 	ctx, cancel := c.timeoutContext()
 	defer cancel()
 
-	imgCls, err := c.newImage(ctx, image.String())
+	imgCloser, err := c.newImage(ctx, image.String())
 	if err != nil {
 		return Manifest{}, err
 	}
-	defer imgCls.Close()
+	defer imgCloser.Close()
 
-	rawManifest, _, err := imgCls.Manifest(ctx)
+	rawManifest, _, err := imgCloser.Manifest(ctx)
 	if err != nil {
 		return Manifest{}, err
 	}
 
-	imgInspect, err := imgCls.Inspect(ctx)
+	imgInspect, err := imgCloser.Inspect(ctx)
 	if err != nil {
 		return Manifest{}, err
 	}
@@ -52,16 +52,20 @@ func (c *Client) Manifest(image Image) (Manifest, error) {
 		imgTag = image.Tag
 	}
 
+	imgPlatform := fmt.Sprintf("%s/%s", imgInspect.Os, imgInspect.Architecture)
+	if imgInspect.Variant != "" {
+		imgPlatform = fmt.Sprintf("%s/%s", imgPlatform, imgInspect.Variant)
+	}
+
 	return Manifest{
-		Name:          imgCls.Reference().DockerReference().Name(),
+		Name:          imgCloser.Reference().DockerReference().Name(),
 		Tag:           imgTag,
 		MIMEType:      manifest.GuessMIMEType(rawManifest),
 		Digest:        imgDigest,
 		Created:       imgInspect.Created,
 		DockerVersion: imgInspect.DockerVersion,
 		Labels:        imgInspect.Labels,
-		Architecture:  imgInspect.Architecture,
-		Os:            imgInspect.Os,
 		Layers:        imgInspect.Layers,
+		Platform:      imgPlatform,
 	}, nil
 }

pkg/registry/manifest_test.go

@@ -0,0 +1,37 @@
+package registry_test
+
+import (
+	"encoding/json"
+	"fmt"
+	"testing"
+
+	"github.com/crazy-max/diun/pkg/registry"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestManifestVariant(t *testing.T) {
+	rc, err := registry.New(registry.Options{
+		ImageOs:      "linux",
+		ImageArch:    "arm",
+		ImageVariant: "v7",
+	})
+	if err != nil {
+		panic(err.Error())
+	}
+
+	img, err := registry.ParseImage("crazymax/diun:2.5.0")
+	if err != nil {
+		t.Error(err)
+	}
+
+	manifest, err := rc.Manifest(img)
+	b, _ := json.MarshalIndent(manifest, "", "  ")
+	fmt.Println(string(b))
+
+	assert.NoError(t, err)
+	assert.Equal(t, "docker.io/crazymax/diun", manifest.Name)
+	assert.Equal(t, "2.5.0", manifest.Tag)
+	assert.Equal(t, "application/vnd.docker.distribution.manifest.list.v2+json", manifest.MIMEType)
+	assert.Equal(t, "linux/arm/v7", manifest.Platform)
+	assert.Empty(t, manifest.DockerVersion)
+}

pkg/registry/registry.go

@@ -18,13 +18,14 @@ type Client struct {
 
 // Options holds docker registry object options
 type Options struct {
-	Os          string
-	Arch        string
-	Username    string
-	Password    string
-	InsecureTLS bool
-	Timeout     time.Duration
-	UserAgent   string
+	Username     string
+	Password     string
+	InsecureTLS  bool
+	Timeout      time.Duration
+	UserAgent    string
+	ImageOs      string
+	ImageArch    string
+	ImageVariant string
 }
 
 // New creates new docker registry client instance
@@ -40,12 +41,13 @@ func New(opts Options) (*Client, error) {
 
 	// Sys context
 	sysCtx := &types.SystemContext{
-		OSChoice:                          opts.Os,
-		ArchitectureChoice:                opts.Arch,
 		DockerAuthConfig:                  auth,
 		DockerDaemonInsecureSkipTLSVerify: opts.InsecureTLS,
 		DockerInsecureSkipTLSVerify:       types.NewOptionalBool(opts.InsecureTLS),
 		DockerRegistryUserAgent:           opts.UserAgent,
+		OSChoice:                          opts.ImageOs,
+		ArchitectureChoice:                opts.ImageArch,
+		VariantChoice:                     opts.ImageVariant,
 	}
 
 	return &Client{

pkg/registry/registry_test.go

@@ -0,0 +1,28 @@
+package registry_test
+
+import (
+	"os"
+	"testing"
+
+	"github.com/crazy-max/diun/pkg/registry"
+	"github.com/stretchr/testify/assert"
+)
+
+var (
+	rc *registry.Client
+)
+
+func TestMain(m *testing.M) {
+	var err error
+
+	rc, err = registry.New(registry.Options{})
+	if err != nil {
+		panic(err.Error())
+	}
+
+	os.Exit(m.Run())
+}
+
+func TestNew(t *testing.T) {
+	assert.NotNil(t, rc)
+}