Introduce network serial caching in sync fast path, optimize DB reads, and add granular cache invalidation

management/internals/shared/fastpathcache/invalidator.go

@@ -0,0 +1,48 @@
+// Package fastpathcache exposes the key prefixes and delete helpers for the
+// Sync fast-path caches so mutation sites outside the gRPC server package
+// can invalidate stale entries without a circular import on the grpc
+// package that owns the read-side cache wrappers.
+package fastpathcache
+
+import (
+	"context"
+
+	"github.com/eko/gocache/lib/v4/cache"
+	cachestore "github.com/eko/gocache/lib/v4/store"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	// ExtraSettingsKeyPrefix matches the prefix used by the read-side
+	// extraSettingsCache in management/internals/shared/grpc. Keep these in
+	// sync; drift would leak stale reads on mutations.
+	ExtraSettingsKeyPrefix = "extra-settings:"
+
+	// PeerGroupsKeyPrefix matches the prefix used by the read-side
+	// peerGroupsCache in management/internals/shared/grpc.
+	PeerGroupsKeyPrefix = "peer-groups:"
+)
+
+// InvalidateExtraSettings removes the cached ExtraSettings entry for the
+// given account from the shared cache store. Safe to call with a nil store
+// and safe to call when no entry exists. Errors are swallowed at debug level
+// so mutation flows never fail because of a cache hiccup.
+func InvalidateExtraSettings(ctx context.Context, store cachestore.StoreInterface, accountID string) {
+	if store == nil {
+		return
+	}
+	if err := cache.New[string](store).Delete(ctx, ExtraSettingsKeyPrefix+accountID); err != nil {
+		log.WithContext(ctx).Debugf("fastpathcache: invalidate extra settings for %s: %v", accountID, err)
+	}
+}
+
+// InvalidatePeerGroups removes the cached peer-groups entry for a peer. Safe
+// to call with a nil store and safe to call when no entry exists.
+func InvalidatePeerGroups(ctx context.Context, store cachestore.StoreInterface, peerID string) {
+	if store == nil {
+		return
+	}
+	if err := cache.New[string](store).Delete(ctx, PeerGroupsKeyPrefix+peerID); err != nil {
+		log.WithContext(ctx).Debugf("fastpathcache: invalidate peer groups for %s: %v", peerID, err)
+	}
+}