Leave remote info orphan figures unknown when a manifest is unreadable (closes #228)

When a manifest could not be read, remote info skipped it, counted that
snapshot's blobs as orphaned and advised running prune. The orphan
figures are now unknown in that case, with no prune advice; --json gives
them as null and lists the unreadable remote keys in
unreadable_manifests. Only a listed manifest.json.zst is read, so a
directory without one, as an interrupted backup leaves, keeps the
figures known.

Names under metadata/ were used unchecked and printed raw. A name that
is not a remote key is now skipped with a warning. A manifest under it
is not read either, so it also leaves the figures unknown; --json counts
such manifests in skipped_manifests.

The closing log line carries the unreadable manifest count in place of
the orphan count.

Model: opus-5-5

README.md

@@ -390,7 +390,13 @@ recipients, and local database statistics.
 
 **`remote info`**: Show storage backend type and location plus detailed
 remote storage inventory: per-snapshot metadata sizes, blob counts, and
-orphaned blob detection.
+orphaned blob detection. A name under `metadata/` that is not a remote
+key is skipped with a warning and is not printed. If a listed
+`manifest.json.zst` cannot be read, or sits under a skipped name, the
+orphaned blob figures are reported as unknown; `--json` gives them as
+`null`, lists the remote key of each unreadable manifest in
+`unreadable_manifests` and counts the manifests under skipped names in
+`skipped_manifests`.
 * `--json`: Output as JSON
 
 **`remote nuke`**: Delete every snapshot's metadata and every blob from the

TODO.md

@@ -22,6 +22,22 @@ the tag exists and is exercised; what is left is merging `next` to
 
 # Completed Steps
 
+- 2026-10-07: Made `remote info` stop reporting a snapshot's blobs as
+  orphaned when its manifest cannot be read, and stop printing raw
+  names from under `metadata/`
+  ([issue #228](https://git.eeqj.de/sneak/vaultik/issues/228)). A
+  manifest it failed to read was skipped, so that snapshot's blobs were
+  counted as orphaned and the report advised running `vaultik prune`.
+  The orphan figures are now unknown in that case, with no prune
+  advice, and `--json` gives them as `null` with the unreadable remote
+  keys in `unreadable_manifests`. A name under `metadata/` that is not
+  64 lowercase hex characters is now skipped with a warning instead of
+  being printed, control characters included. A manifest under a
+  skipped name is then not read either, so it also leaves the orphan
+  figures unknown, and `--json` counts such manifests in
+  `skipped_manifests`. A directory with no manifest in it, as left by an
+  interrupted backup, leaves the figures known.
+
 - 2026-10-07: Made a backup notice a file rewritten with its size
   unchanged and a new mtime in the same second as the one in the index
   ([issue #226](https://git.eeqj.de/sneak/vaultik/issues/226)). The

internal/vaultik/info.go

@@ -183,6 +183,11 @@ type SnapshotMetadataInfo struct {
 	TotalSize    int64  `json:"total_size"`
 	BlobCount    int    `json:"blob_count"`
 	BlobsSize    int64  `json:"blobs_size"`
+
+	// Set when the listing holds this snapshot's manifest.json.zst. A
+	// backup interrupted before its manifest upload leaves a directory
+	// without one, which prune does not treat as a snapshot.
+	hasManifest bool
 }
 
 // RemoteInfoResult contains all remote storage information
@@ -206,9 +211,20 @@ type RemoteInfoResult struct {
 	ReferencedBlobCount int   `json:"referenced_blob_count"`
 	ReferencedBlobSize  int64 `json:"referenced_blob_size"`
 
-	// Orphaned blobs
-	OrphanedBlobCount int   `json:"orphaned_blob_count"`
-	OrphanedBlobSize  int64 `json:"orphaned_blob_size"`
+	// Orphaned blobs. Both stay nil (null in the JSON) when a manifest
+	// was listed but not read, since that snapshot's blobs would be
+	// counted as orphaned.
+	OrphanedBlobCount *int   `json:"orphaned_blob_count"`
+	OrphanedBlobSize  *int64 `json:"orphaned_blob_size"`
+
+	// Remote key of each snapshot whose manifest could not be read
+	UnreadableManifests []string `json:"unreadable_manifests,omitempty"`
+
+	// Number of manifests not read because the name above them under
+	// metadata/ is not a remote key. The names themselves are not
+	// reported: they come from the destination store and may hold
+	// control characters.
+	SkippedManifests int `json:"skipped_manifests,omitempty"`
 }
 
 // RemoteInfo displays information about remote storage
@@ -234,16 +250,20 @@ func (v *Vaultik) RemoteInfo(jsonOutput bool) error {
 		v.stdoutf("Scanning snapshot metadata...\n")
 	}
 
-	snapshotMetadata, snapshotIDs, err := v.collectSnapshotMetadata()
+	snapshotMetadata, snapshotIDs, skippedManifests, err := v.collectSnapshotMetadata()
 	if err != nil {
 		return err
 	}
 
+	result.SkippedManifests = skippedManifests
+
 	if showText {
 		v.stdoutf("Downloading %d manifest(s)...\n", len(snapshotIDs))
 	}
 
-	referencedBlobs := v.collectReferencedBlobsFromManifests(snapshotIDs, snapshotMetadata)
+	referencedBlobs, unreadableManifests := v.collectReferencedBlobsFromManifests(
+		snapshotIDs, snapshotMetadata)
+	result.UnreadableManifests = unreadableManifests
 
 	v.populateRemoteInfoResult(result, snapshotMetadata, snapshotIDs, referencedBlobs)
 
@@ -256,7 +276,7 @@ func (v *Vaultik) RemoteInfo(jsonOutput bool) error {
 		"snapshots", result.TotalMetadataCount,
 		"total_blobs", result.TotalBlobCount,
 		"referenced_blobs", result.ReferencedBlobCount,
-		"orphaned_blobs", result.OrphanedBlobCount)
+		"unreadable_manifests", len(result.UnreadableManifests))
 
 	if jsonOutput {
 		enc := json.NewEncoder(v.Stdout)
@@ -273,16 +293,18 @@ func (v *Vaultik) RemoteInfo(jsonOutput bool) error {
 }
 
 // collectSnapshotMetadata scans remote metadata and returns
-// per-snapshot info and sorted IDs.
+// per-snapshot info, sorted IDs and the number of manifests it skipped
+// because the name above them is not a remote key.
 func (v *Vaultik) collectSnapshotMetadata() (
-	map[string]*SnapshotMetadataInfo, []string, error,
+	map[string]*SnapshotMetadataInfo, []string, int, error,
 ) {
 	snapshotMetadata := make(map[string]*SnapshotMetadataInfo)
+	skippedManifests := 0
 
 	metadataCh := v.Storage.ListStream(v.ctx, "metadata/")
 	for obj := range metadataCh {
 		if obj.Err != nil {
-			return nil, nil, fmt.Errorf("listing metadata: %w", obj.Err)
+			return nil, nil, 0, fmt.Errorf("listing metadata: %w", obj.Err)
 		}
 
 		parts := strings.Split(obj.Key, "/")
@@ -291,6 +313,22 @@ func (v *Vaultik) collectSnapshotMetadata() (
 		}
 
 		snapshotID := parts[1]
+		filename := parts[2]
+		isManifest := filename == "manifest.json.zst"
+
+		// The name comes from the destination store, which is not
+		// trusted, and is printed in the report. Accept it only in the
+		// form of a remote key.
+		if !isBlobHash(snapshotID) {
+			log.Warn("Skipping non-conforming key under metadata/",
+				"key", obj.Key)
+
+			if isManifest {
+				skippedManifests++
+			}
+
+			continue
+		}
 
 		if _, exists := snapshotMetadata[snapshotID]; !exists {
 			snapshotMetadata[snapshotID] = &SnapshotMetadataInfo{SnapshotID: snapshotID}
@@ -298,7 +336,10 @@ func (v *Vaultik) collectSnapshotMetadata() (
 
 		info := snapshotMetadata[snapshotID]
 
-		filename := parts[2]
+		if isManifest {
+			info.hasManifest = true
+		}
+
 		if strings.HasPrefix(filename, "manifest") {
 			info.ManifestSize = obj.Size
 		} else if strings.HasPrefix(filename, "db") {
@@ -315,17 +356,25 @@ func (v *Vaultik) collectSnapshotMetadata() (
 
 	sort.Strings(snapshotIDs)
 
-	return snapshotMetadata, snapshotIDs, nil
+	return snapshotMetadata, snapshotIDs, skippedManifests, nil
 }
 
-// collectReferencedBlobsFromManifests downloads manifests and returns
-// referenced blob hashes with sizes.
+// collectReferencedBlobsFromManifests downloads the listed manifests
+// and returns referenced blob hashes with sizes, and the remote keys
+// of the manifests it could not read.
 func (v *Vaultik) collectReferencedBlobsFromManifests(
 	snapshotIDs []string, snapshotMetadata map[string]*SnapshotMetadataInfo,
-) map[string]int64 {
+) (map[string]int64, []string) {
 	referencedBlobs := make(map[string]int64)
 
+	var unreadable []string
+
 	for _, snapshotID := range snapshotIDs {
+		info := snapshotMetadata[snapshotID]
+		if !info.hasManifest {
+			continue
+		}
+
 		// snapshotIDs here are remote keys, taken straight from the
 		// metadata/ listing. downloadManifestByKey is the single reader
 		// for remote manifests; see its doc comment.
@@ -333,10 +382,11 @@ func (v *Vaultik) collectReferencedBlobsFromManifests(
 		if err != nil {
 			log.Warn("Failed to read manifest", "snapshot", snapshotID, "error", err)
 
+			unreadable = append(unreadable, snapshotID)
+
 			continue
 		}
 
-		info := snapshotMetadata[snapshotID]
 		info.BlobCount = manifest.BlobCount
 
 		var blobsSize int64
@@ -349,7 +399,7 @@ func (v *Vaultik) collectReferencedBlobsFromManifests(
 		info.BlobsSize = blobsSize
 	}
 
-	return referencedBlobs
+	return referencedBlobs, unreadable
 }
 
 // populateRemoteInfoResult fills in the result's snapshot and
@@ -378,8 +428,9 @@ func (v *Vaultik) populateRemoteInfoResult(
 }
 
 // scanRemoteBlobStorage lists all blobs on remote and computes orphan
-// stats. showText is true only when the human report is being printed
-// (not --json, not --quiet), gating the progress line.
+// stats when every listed manifest was read. showText is true only
+// when the human report is being printed (not --json, not --quiet),
+// gating the progress line.
 func (v *Vaultik) scanRemoteBlobStorage(
 	result *RemoteInfoResult, referencedBlobs map[string]int64, showText bool,
 ) error {
@@ -406,13 +457,28 @@ func (v *Vaultik) scanRemoteBlobStorage(
 		result.TotalBlobSize += obj.Size
 	}
 
+	// A blob named only by a manifest that could not be read, or by one
+	// under a skipped name, would be counted as orphaned, so the orphan
+	// figures stay unknown.
+	if len(result.UnreadableManifests) > 0 || result.SkippedManifests > 0 {
+		return nil
+	}
+
+	var (
+		orphanedCount int
+		orphanedSize  int64
+	)
+
 	for hash, size := range allBlobs {
 		if _, referenced := referencedBlobs[hash]; !referenced {
-			result.OrphanedBlobCount++
-			result.OrphanedBlobSize += size
+			orphanedCount++
+			orphanedSize += size
 		}
 	}
 
+	result.OrphanedBlobCount = &orphanedCount
+	result.OrphanedBlobSize = &orphanedSize
+
 	return nil
 }
 
@@ -465,11 +531,21 @@ func (v *Vaultik) printRemoteInfoTable(result *RemoteInfoResult) {
 	v.stdoutf("Referenced by snapshots:    %s (%s)\n",
 		humanize.Comma(int64(result.ReferencedBlobCount)),
 		ubytes(result.ReferencedBlobSize))
-	v.stdoutf("Orphaned (unreferenced):    %s (%s)\n",
-		humanize.Comma(int64(result.OrphanedBlobCount)),
-		ubytes(result.OrphanedBlobSize))
 
-	if result.OrphanedBlobCount > 0 {
+	if result.OrphanedBlobCount == nil {
+		v.stdoutf("Orphaned (unreferenced):    unknown "+
+			"(%d manifest(s) could not be read, "+
+			"%d manifest(s) under a non-conforming name skipped)\n",
+			len(result.UnreadableManifests), result.SkippedManifests)
+
+		return
+	}
+
+	v.stdoutf("Orphaned (unreferenced):    %s (%s)\n",
+		humanize.Comma(int64(*result.OrphanedBlobCount)),
+		ubytes(*result.OrphanedBlobSize))
+
+	if *result.OrphanedBlobCount > 0 {
 		v.stdoutf("\nRun 'vaultik prune' to remove orphaned blobs.\n")
 	}
 }

internal/vaultik/remote_info_test.go

@@ -0,0 +1,158 @@
+package vaultik_test
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"sneak.berlin/go/vaultik/internal/log"
+	"sneak.berlin/go/vaultik/internal/snapshot"
+)
+
+// testBlobHashB is a blob that the manifest written by addRemote does
+// not reference.
+const testBlobHashB = "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb" +
+	"bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
+
+// TestRemoteInfo_UnreadableManifestLeavesOrphansUnknown checks that a
+// manifest remote info cannot read makes the orphan figures unknown. A
+// blob referenced only by that snapshot would otherwise be counted as
+// orphaned, and the report would advise running prune.
+func TestRemoteInfo_UnreadableManifestLeavesOrphansUnknown(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	env := newListEnv(t)
+
+	// The readable manifest references blob A only.
+	env.addRemote(t, listRemoteID, time.Date(2026, 3, 2, 0, 0, 0, 0, time.UTC))
+	addBlob(t, env.store.testStorer, testBlobHashA)
+	addBlob(t, env.store.testStorer, testBlobHashB)
+
+	// With every manifest readable, blob B is orphaned.
+	require.NoError(t, env.v.RemoteInfo(true))
+
+	var doc map[string]any
+
+	require.NoError(t, json.Unmarshal(env.stdout.Bytes(), &doc))
+	assert.InDelta(t, 1, doc["orphaned_blob_count"], 0)
+
+	// A second snapshot whose manifest cannot be decoded. Blob B may be
+	// one of its blobs.
+	unreadableKey := snapshot.RemoteSnapshotKey(listLocalID)
+	require.NoError(t, env.store.Put(context.Background(),
+		"metadata/"+unreadableKey+"/manifest.json.zst",
+		bytes.NewReader([]byte("not a valid manifest"))))
+
+	env.stdout.Reset()
+	require.NoError(t, env.v.RemoteInfo(false))
+
+	text := env.stdout.String()
+	assert.Contains(t, text, "Orphaned (unreferenced):    unknown "+
+		"(1 manifest(s) could not be read, "+
+		"0 manifest(s) under a non-conforming name skipped)")
+	assert.NotContains(t, text, "vaultik prune")
+
+	env.stdout.Reset()
+	require.NoError(t, env.v.RemoteInfo(true))
+
+	doc = nil
+	require.NoError(t, json.Unmarshal(env.stdout.Bytes(), &doc))
+	assert.Contains(t, doc, "orphaned_blob_count")
+	assert.Nil(t, doc["orphaned_blob_count"])
+	assert.Contains(t, doc, "orphaned_blob_size")
+	assert.Nil(t, doc["orphaned_blob_size"])
+	assert.Equal(t, []any{unreadableKey}, doc["unreadable_manifests"])
+}
+
+// TestRemoteInfo_SkipsNonConformingMetadataName checks that a directory
+// under metadata/ whose name is not a remote key is left out of the
+// report, and that the orphan figures are unknown when it holds a
+// manifest. The name comes from the destination store; printed raw, its
+// control characters would reach the terminal. Its manifest is not
+// read, so a blob only it references would otherwise be counted as
+// orphaned.
+func TestRemoteInfo_SkipsNonConformingMetadataName(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	env := newListEnv(t)
+	env.addRemote(t, listRemoteID, time.Date(2026, 3, 2, 0, 0, 0, 0, time.UTC))
+	addBlob(t, env.store.testStorer, testBlobHashA)
+	addBlob(t, env.store.testStorer, testBlobHashB)
+	require.NoError(t, env.store.Put(context.Background(),
+		"metadata/\x1b[31mred/manifest.json.zst",
+		bytes.NewReader([]byte("not a valid manifest"))))
+
+	require.NoError(t, env.v.RemoteInfo(false))
+
+	text := env.stdout.String()
+	assert.NotContains(t, text, "\x1b")
+	assert.NotContains(t, text, "31mred")
+	assert.Contains(t, text, "Total (1 snapshots)")
+	assert.Contains(t, text, "Orphaned (unreferenced):    unknown "+
+		"(0 manifest(s) could not be read, "+
+		"1 manifest(s) under a non-conforming name skipped)")
+	assert.NotContains(t, text, "vaultik prune")
+
+	env.stdout.Reset()
+	require.NoError(t, env.v.RemoteInfo(true))
+
+	out := env.stdout.String()
+	assert.NotContains(t, out, "31mred")
+
+	var doc map[string]any
+
+	require.NoError(t, json.Unmarshal([]byte(out), &doc))
+	assert.Contains(t, doc, "orphaned_blob_count")
+	assert.Nil(t, doc["orphaned_blob_count"])
+	assert.Contains(t, doc, "orphaned_blob_size")
+	assert.Nil(t, doc["orphaned_blob_size"])
+	assert.InDelta(t, 1, doc["skipped_manifests"], 0)
+	assert.NotContains(t, doc, "unreadable_manifests")
+}
+
+// TestRemoteInfo_DirectoryWithoutManifestLeavesOrphansKnown checks that
+// a directory under metadata/ holding no manifest.json.zst, such as one
+// left by a backup interrupted before its manifest upload, leaves the
+// orphan figures known. prune does not treat such a directory as a
+// snapshot and deletes the blobs the report lists as orphaned.
+func TestRemoteInfo_DirectoryWithoutManifestLeavesOrphansKnown(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	env := newListEnv(t)
+	env.addRemote(t, listRemoteID, time.Date(2026, 3, 2, 0, 0, 0, 0, time.UTC))
+	addBlob(t, env.store.testStorer, testBlobHashA)
+	addBlob(t, env.store.testStorer, testBlobHashB)
+
+	// One directory under a remote key and one under a non-conforming
+	// name, each holding only a database.
+	names := []string{snapshot.RemoteSnapshotKey(listLocalID), "\x1b[31mred"}
+	for _, name := range names {
+		require.NoError(t, env.store.Put(context.Background(),
+			"metadata/"+name+"/db.zst.age",
+			bytes.NewReader([]byte("not a valid database"))))
+	}
+
+	require.NoError(t, env.v.RemoteInfo(false))
+
+	text := env.stdout.String()
+	assert.NotContains(t, text, "\x1b")
+	assert.Contains(t, text, "Orphaned (unreferenced):    1 (")
+	assert.Contains(t, text, "Run 'vaultik prune' to remove orphaned blobs.")
+
+	env.stdout.Reset()
+	require.NoError(t, env.v.RemoteInfo(true))
+
+	var doc map[string]any
+
+	require.NoError(t, json.Unmarshal(env.stdout.Bytes(), &doc))
+	assert.InDelta(t, 1, doc["orphaned_blob_count"], 0)
+	assert.NotContains(t, doc, "unreadable_manifests")
+	assert.NotContains(t, doc, "skipped_manifests")
+}