Add helper for DHT-backed temporal persistence

pkg/slurp/temporal/dht_builder.go

@@ -0,0 +1,67 @@
+package temporal
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"chorus/pkg/dht"
+	"chorus/pkg/slurp/storage"
+)
+
+// NewDHTBackedTemporalGraphSystem constructs a temporal graph system whose persistence
+// layer replicates snapshots through the provided libp2p DHT. When no DHT instance is
+// supplied the function falls back to local-only persistence so callers can degrade
+// gracefully during bring-up.
+func NewDHTBackedTemporalGraphSystem(
+	ctx context.Context,
+	contextStore storage.ContextStore,
+	localStorage storage.LocalStorage,
+	dhtInstance dht.DHT,
+	nodeID string,
+	cfg *TemporalConfig,
+) (*TemporalGraphSystem, error) {
+	if contextStore == nil {
+		return nil, fmt.Errorf("context store is required")
+	}
+	if localStorage == nil {
+		return nil, fmt.Errorf("local storage is required")
+	}
+	if cfg == nil {
+		cfg = DefaultTemporalConfig()
+	}
+
+	// Ensure persistence is configured for distributed replication when a DHT is present.
+	if cfg.PersistenceConfig == nil {
+		cfg.PersistenceConfig = defaultPersistenceConfig()
+	}
+	cfg.PersistenceConfig.EnableLocalStorage = true
+	cfg.PersistenceConfig.EnableDistributedStorage = dhtInstance != nil
+
+	// Disable write buffering by default so we do not depend on ContextStore batch APIs
+	// when callers only wire the DHT layer.
+	cfg.PersistenceConfig.EnableWriteBuffer = false
+	cfg.PersistenceConfig.BatchSize = 1
+
+	if nodeID == "" {
+		nodeID = fmt.Sprintf("slurp-node-%d", time.Now().UnixNano())
+	}
+
+	var distributed storage.DistributedStorage
+	if dhtInstance != nil {
+		distributed = storage.NewDistributedStorage(dhtInstance, nodeID, nil)
+	}
+
+	factory := NewTemporalGraphFactory(contextStore, cfg)
+
+	system, err := factory.CreateTemporalGraphSystem(localStorage, distributed, nil, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create temporal graph system: %w", err)
+	}
+
+	if err := system.PersistenceManager.LoadTemporalGraph(ctx); err != nil {
+		return nil, fmt.Errorf("failed to load temporal graph: %w", err)
+	}
+
+	return system, nil
+}