Bound remote control object reads

internal/artifacts/current_state_legacy.go

@@ -1,7 +1,9 @@
 package artifacts
 
 import (
+	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"strings"
@@ -10,6 +12,13 @@ import (
 	"gitea.maximumdirect.net/eric/narratio/internal/manifest"
 )
 
+const (
+	// MaxLegacyCurrentRunPointerBytes bounds the compatibility run selector.
+	MaxLegacyCurrentRunPointerBytes int64 = 4 << 10
+	// MaxLegacyCurrentManifestBytes bounds the compatibility session manifest.
+	MaxLegacyCurrentManifestBytes int64 = MaxRemoteSessionManifestBytes
+)
+
 // This file is temporary compatibility support for sessions published before
 // immutable current commits. It can be removed after legacy remote state is migrated.
 
@@ -48,17 +57,12 @@ func loadLegacyCurrentRunPointer(ctx context.Context, store storage.ObjectStore,
 		return "", fmt.Errorf("current run pointer key is required")
 	}
 
-	exists, err := store.Exists(ctx, key)
+	_, data, err := readCurrentStateControlObject(ctx, store, key, "legacy current run pointer", MaxLegacyCurrentRunPointerBytes)
 	if err != nil {
-		return "", fmt.Errorf("check current run pointer %q: %w", key, err)
-	}
-	if !exists {
-		return "", &CurrentRunPointerMissingError{Key: key}
-	}
-
-	data, err := downloadRemoteObject(ctx, store, key, "narratio-legacy-current-run-id-*.txt")
-	if err != nil {
-		return "", fmt.Errorf("download current run pointer %q: %w", key, err)
+		if errors.Is(err, os.ErrNotExist) {
+			return "", &CurrentRunPointerMissingError{Key: key}
+		}
+		return "", err
 	}
 	runID := strings.TrimSpace(string(data))
 	if runID == "" {
@@ -76,21 +80,15 @@ func loadLegacyCurrentManifest(ctx context.Context, store storage.ObjectStore, c
 		return nil, fmt.Errorf("current manifest key is required")
 	}
 
-	exists, err := store.Exists(ctx, key)
+	_, data, err := readCurrentStateControlObject(ctx, store, key, "legacy current manifest", MaxLegacyCurrentManifestBytes)
 	if err != nil {
-		return nil, fmt.Errorf("check current manifest %q: %w", key, err)
-	}
-	if !exists {
-		return nil, &CurrentManifestMissingError{Key: key}
+		if errors.Is(err, os.ErrNotExist) {
+			return nil, &CurrentManifestMissingError{Key: key}
+		}
+		return nil, err
 	}
 
-	localPath, err := storage.DownloadObjectToTemp(ctx, store, key, "narratio-legacy-current-manifest-*.json")
-	if err != nil {
-		return nil, fmt.Errorf("download current manifest %q: %w", key, err)
-	}
-	defer func() { _ = os.Remove(localPath) }()
-
-	m, err := (&manifest.LocalStore{}).Load(ctx, localPath)
+	m, err := (&manifest.LocalStore{}).LoadReader(ctx, bytes.NewReader(data))
 	if err != nil {
 		return nil, fmt.Errorf("current manifest decode failed: %w", err)
 	}