fix(offsite): 服务器或白名单按摘要钉住的 felis/ 与 mirror/ 版本也进异地副本，恢复只按摘要推回不动安装器的 tag

internal/offsite/images.go

@@ -1,10 +1,13 @@
 package offsite
 
-// The off-site copy of the platform registry's user images. The installer
-// pushes everything under felis/ and mirror/ again on any host, so those are
-// left out; every other repository holds builds that exist nowhere else: a
-// lost registry volume would otherwise leave each server pinned to one of them
-// in ImagePullBackOff until someone rebuilds it.
+// The off-site copy of the platform registry's user images. Every repository
+// outside felis/ and mirror/ holds builds that exist nowhere else: a lost
+// registry volume would otherwise leave each server pinned to one of them in
+// ImagePullBackOff until someone rebuilds it. The installer pushes felis/ and
+// mirror/ again on any host, but under the same tags at new digests (a build
+// is not reproducible, an upstream tag moves on), so from those only the
+// revisions a server or a whitelist entry pins by digest are copied, without
+// their tags: the tags belong to whatever the installer pushed last.
 //
 // The bucket holds each blob and manifest once, by digest, encrypted like
 // everything else, plus an index that says which repository holds which
@@ -234,19 +237,28 @@ func (s *Syncer) syncImages(ctx context.Context, res *Result, fail func(string,
 		return
 	}
 	sort.Strings(repos)
-	listed := map[string]bool{}
+	pins, pinsKnown := map[string][]string{}, true
+	if s.ImagePins != nil {
+		if pins, err = s.ImagePins(ctx); err != nil {
+			fail("list the images servers and the whitelist pin: %v", err)
+			pinsKnown, c.failed = false, true
+		}
+	}
 	for _, repo := range repos {
-		if reservedRepo(repo) {
+		if reservedRepo(repo) && !pinsKnown {
+			c.carry(repo)
+			continue
+		}
+		if reservedRepo(repo) && len(pins[repo]) == 0 {
 			continue
 		}
-		listed[repo] = true
 		if ctx.Err() != nil {
 			c.fail("stopped before %s: %v", repo, ctx.Err())
 			c.failed = true
 			c.carry(repo)
 			continue
 		}
-		c.repo(ctx, repo)
+		c.repo(ctx, repo, pins[repo])
 	}
 
 	stamp := ""
@@ -277,9 +289,10 @@ func (s *Syncer) syncImages(ctx context.Context, res *Result, fail func(string,
 	}
 }
 
-// repo copies one repository into c.next. A repository that cannot be read in
-// full keeps the entry the previous index had for it.
-func (c *imageCopy) repo(ctx context.Context, repo string) {
+// repo copies one repository into c.next; of a reserved one, only the pinned
+// revisions and none of its tags. A repository that cannot be read in full
+// keeps the entry the previous index had for it.
+func (c *imageCopy) repo(ctx context.Context, repo string, pinned []string) {
 	digests, tags, err := c.s.Images.Revisions(ctx, repo)
 	if err != nil {
 		c.fail("list the images of %s: %v", repo, err)
@@ -287,6 +300,10 @@ func (c *imageCopy) repo(ctx context.Context, repo string) {
 		c.carry(repo)
 		return
 	}
+	if reservedRepo(repo) {
+		digests = slices.DeleteFunc(digests, func(d string) bool { return !slices.Contains(pinned, d) })
+		tags = nil
+	}
 	entry := ImageRepo{Tags: map[string]string{}}
 	short := false
 	for _, d := range digests {
@@ -732,6 +749,9 @@ func FetchImages(ctx context.Context, b Bucket, key []byte, x *ImageIndex, t Ima
 	pushedBlobs := map[string]bool{}
 	for _, repo := range slices.Sorted(maps.Keys(x.Repositories)) {
 		entry := x.Repositories[repo]
+		if reservedRepo(repo) {
+			entry.Tags = nil // the installer's tags stay where it put them
+		}
 		done := map[string]bool{}
 		var push func(d string) error
 		push = func(d string) error {

internal/offsite/images_test.go

@@ -280,6 +280,68 @@ func TestSyncImagesCopiesUserImages(t *testing.T) {
 	}
 }
 
+// TestSyncImagesCopiesPinnedPlatformRevisions: of felis/ and mirror/ only the
+// revisions a pin names are copied, without tags; a restore puts them back by
+// digest and leaves the tags the installer pushed on the new host alone. When
+// the pins cannot be read, the previous copy of those revisions is kept and
+// the run fails.
+func TestSyncImagesCopiesPinnedPlatformRevisions(t *testing.T) {
+	reg := newFakeRegistry()
+	old := reg.image("felis/paper", "demo", layer(4000))
+	current := reg.image("felis/paper", "demo", layer(4000))
+	reg.image("mirror/trivy", "1", layer(2000))
+	user := reg.image("user/a", "v1", layer(1000))
+
+	s, b, clock := newImageSyncer(t, reg)
+	s.ImagePins = func(context.Context) (map[string][]string, error) {
+		return map[string][]string{"felis/paper": {old}, "user/a": {user}}, nil
+	}
+	res, err := s.Run(context.Background())
+	if err != nil {
+		t.Fatalf("Run: %v", err)
+	}
+	x, err := LoadImageIndex(context.Background(), b, s.Key, res.ImageIndex)
+	if err != nil {
+		t.Fatal(err)
+	}
+	paper, ok := x.Repositories["felis/paper"]
+	if !ok || !slices.Equal(paper.Manifests, []string{old}) || len(paper.Tags) != 0 {
+		t.Fatalf("felis/paper = %+v, want only the pinned %s and no tags", paper, old)
+	}
+	if _, ok := x.Repositories["mirror/trivy"]; ok {
+		t.Fatal("unpinned mirror/trivy was copied")
+	}
+	if got := x.Repositories["user/a"]; got.Tags["v1"] != user {
+		t.Fatalf("user/a = %+v", got)
+	}
+
+	fresh := newFakeRegistry()
+	rebuilt := fresh.image("felis/paper", "demo", layer(4000))
+	if _, err := FetchImages(context.Background(), b, s.Key, x, fresh, nil); err != nil {
+		t.Fatalf("FetchImages: %v", err)
+	}
+	if got := fresh.repos["felis/paper"]; got.tags["demo"] != rebuilt || !slices.Contains(got.digests, old) {
+		t.Fatalf("restored felis/paper: tags %v digests %v, want demo=%s and %s present", got.tags, got.digests, rebuilt, old)
+	}
+	if slices.Contains(fresh.repos["felis/paper"].digests, current) {
+		t.Fatal("the unpinned revision was restored")
+	}
+
+	*clock = clock.Add(time.Hour)
+	s.ImagePins = func(context.Context) (map[string][]string, error) { return nil, errors.New("cluster down") }
+	res, err = s.Run(context.Background())
+	if err == nil {
+		t.Fatal("Run succeeded without the pins")
+	}
+	x, err = LoadImageIndex(context.Background(), b, s.Key, res.ImageIndex)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := x.Repositories["felis/paper"]; !slices.Equal(got.Manifests, []string{old}) {
+		t.Fatalf("without the pins felis/paper = %+v, want the previous copy kept", got)
+	}
+}
+
 // TestSyncImagesRejectsCorruptBlob: bytes that do not hash to the digest never
 // become that digest's object, the image stays out of the index, and the run
 // fails so the next one tries again.

internal/offsite/sync.go

@@ -95,6 +95,10 @@ type Syncer struct {
 	// Images is the platform registry whose user images are copied (images.go);
 	// nil copies none.
 	Images ImageSource
+	// ImagePins lists, per repository, the digests a server's spec or a
+	// whitelist entry pins. Under felis/ and mirror/ only those revisions are
+	// copied (images.go); nil copies none there.
+	ImagePins func(ctx context.Context) (map[string][]string, error)
 	// UploadsDir is the host directory of the uploads volume, whose submission
 	// contexts are copied (uploads.go); empty copies none.
 	UploadsDir string

internal/registryprune/prune.go

@@ -172,7 +172,7 @@ func (p *Pruner) log() *slog.Logger {
 func Plan(indexes map[string]*registrygate.Index, refs []string, host string, now time.Time, grace time.Duration, keepTagged int) []Target {
 	keep := map[Target]bool{}
 	for _, ref := range refs {
-		repo, tag, digest, ok := parseRef(ref, host)
+		repo, tag, digest, ok := ParseRef(ref, host)
 		if !ok {
 			continue
 		}
@@ -255,9 +255,9 @@ func reserved(repo string) bool {
 	return false
 }
 
-// parseRef splits host/repo[:tag][@digest] for refs under host. A ref with
+// ParseRef splits host/repo[:tag][@digest] for refs under host. A ref with
 // neither tag nor digest means :latest, as it does for every image client.
-func parseRef(ref, host string) (repo, tag, digest string, ok bool) {
+func ParseRef(ref, host string) (repo, tag, digest string, ok bool) {
 	rest, ok := strings.CutPrefix(strings.TrimSpace(ref), host+"/")
 	if !ok || rest == "" {
 		return "", "", "", false

internal/registryprune/prune_test.go

@@ -124,9 +124,9 @@ func TestParseRef(t *testing.T) {
 		{"other:5000/felis/paper:demo", "", "", "", false},
 		{host + "/", "", "", "", false},
 	} {
-		repo, tag, digest, ok := parseRef(c.ref, host)
+		repo, tag, digest, ok := ParseRef(c.ref, host)
 		if repo != c.repo || tag != c.tag || digest != c.digest || ok != c.ok {
-			t.Errorf("parseRef(%q) = %q %q %q %v, want %q %q %q %v", c.ref, repo, tag, digest, ok, c.repo, c.tag, c.digest, c.ok)
+			t.Errorf("ParseRef(%q) = %q %q %q %v, want %q %q %q %v", c.ref, repo, tag, digest, ok, c.repo, c.tag, c.digest, c.ok)
 		}
 	}
 }