snapshot of https://github.com/seaweedfs/seaweedfs.git (master, 2026-09-16; blobs > 131072B omitted)

weed/iam/util/generic_cache.go

@@ -0,0 +1,175 @@
+package util
+
+import (
+	"context"
+	"time"
+
+	"github.com/karlseguin/ccache/v2"
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+)
+
+// CacheableStore defines the interface for stores that can be cached
+type CacheableStore[T any] interface {
+	Get(ctx context.Context, filerAddress string, key string) (T, error)
+	Store(ctx context.Context, filerAddress string, key string, value T) error
+	Delete(ctx context.Context, filerAddress string, key string) error
+	List(ctx context.Context, filerAddress string) ([]string, error)
+}
+
+// CopyFunction defines how to deep copy cached values
+type CopyFunction[T any] func(T) T
+
+// CachedStore provides generic TTL caching for any store type
+type CachedStore[T any] struct {
+	baseStore CacheableStore[T]
+	cache     *ccache.Cache
+	listCache *ccache.Cache
+	copyFunc  CopyFunction[T]
+	ttl       time.Duration
+	listTTL   time.Duration
+}
+
+// CachedStoreConfig holds configuration for the generic cached store
+type CachedStoreConfig struct {
+	TTL          time.Duration
+	ListTTL      time.Duration
+	MaxCacheSize int64
+}
+
+// NewCachedStore creates a new generic cached store
+func NewCachedStore[T any](
+	baseStore CacheableStore[T],
+	copyFunc CopyFunction[T],
+	config CachedStoreConfig,
+) *CachedStore[T] {
+	// Apply defaults
+	if config.TTL == 0 {
+		config.TTL = 5 * time.Minute
+	}
+	if config.ListTTL == 0 {
+		config.ListTTL = 1 * time.Minute
+	}
+	if config.MaxCacheSize == 0 {
+		config.MaxCacheSize = 1000
+	}
+
+	// Create ccache instances
+	pruneCount := config.MaxCacheSize >> 3
+	if pruneCount <= 0 {
+		pruneCount = 100
+	}
+
+	return &CachedStore[T]{
+		baseStore: baseStore,
+		cache:     ccache.New(ccache.Configure().MaxSize(config.MaxCacheSize).ItemsToPrune(uint32(pruneCount))),
+		listCache: ccache.New(ccache.Configure().MaxSize(100).ItemsToPrune(10)),
+		copyFunc:  copyFunc,
+		ttl:       config.TTL,
+		listTTL:   config.ListTTL,
+	}
+}
+
+// Get retrieves an item with caching
+func (c *CachedStore[T]) Get(ctx context.Context, filerAddress string, key string) (T, error) {
+	// Try cache first
+	item := c.cache.Get(key)
+	if item != nil {
+		// Cache hit - return cached item (DO NOT extend TTL)
+		value := item.Value().(T)
+		glog.V(4).Infof("Cache hit for key %s", key)
+		return c.copyFunc(value), nil
+	}
+
+	// Cache miss - fetch from base store
+	glog.V(4).Infof("Cache miss for key %s, fetching from store", key)
+	value, err := c.baseStore.Get(ctx, filerAddress, key)
+	if err != nil {
+		var zero T
+		return zero, err
+	}
+
+	// Cache the result with TTL
+	c.cache.Set(key, c.copyFunc(value), c.ttl)
+	glog.V(3).Infof("Cached key %s with TTL %v", key, c.ttl)
+	return value, nil
+}
+
+// Store stores an item and invalidates cache
+func (c *CachedStore[T]) Store(ctx context.Context, filerAddress string, key string, value T) error {
+	// Store in base store
+	err := c.baseStore.Store(ctx, filerAddress, key, value)
+	if err != nil {
+		return err
+	}
+
+	// Invalidate cache entries
+	c.cache.Delete(key)
+	c.listCache.Clear() // Invalidate list cache
+
+	glog.V(3).Infof("Stored and invalidated cache for key %s", key)
+	return nil
+}
+
+// Delete deletes an item and invalidates cache
+func (c *CachedStore[T]) Delete(ctx context.Context, filerAddress string, key string) error {
+	// Delete from base store
+	err := c.baseStore.Delete(ctx, filerAddress, key)
+	if err != nil {
+		return err
+	}
+
+	// Invalidate cache entries
+	c.cache.Delete(key)
+	c.listCache.Clear() // Invalidate list cache
+
+	glog.V(3).Infof("Deleted and invalidated cache for key %s", key)
+	return nil
+}
+
+// List lists all items with caching
+func (c *CachedStore[T]) List(ctx context.Context, filerAddress string) ([]string, error) {
+	const listCacheKey = "item_list"
+
+	// Try list cache first
+	item := c.listCache.Get(listCacheKey)
+	if item != nil {
+		// Cache hit - return cached list (DO NOT extend TTL)
+		items := item.Value().([]string)
+		glog.V(4).Infof("List cache hit, returning %d items", len(items))
+		return append([]string(nil), items...), nil // Return a copy
+	}
+
+	// Cache miss - fetch from base store
+	glog.V(4).Infof("List cache miss, fetching from store")
+	items, err := c.baseStore.List(ctx, filerAddress)
+	if err != nil {
+		return nil, err
+	}
+
+	// Cache the result with TTL (store a copy)
+	itemsCopy := append([]string(nil), items...)
+	c.listCache.Set(listCacheKey, itemsCopy, c.listTTL)
+	glog.V(3).Infof("Cached list with %d entries, TTL %v", len(items), c.listTTL)
+	return items, nil
+}
+
+// ClearCache clears all cached entries
+func (c *CachedStore[T]) ClearCache() {
+	c.cache.Clear()
+	c.listCache.Clear()
+	glog.V(2).Infof("Cleared all cache entries")
+}
+
+// GetCacheStats returns cache statistics
+func (c *CachedStore[T]) GetCacheStats() map[string]interface{} {
+	return map[string]interface{}{
+		"itemCache": map[string]interface{}{
+			"size": c.cache.ItemCount(),
+			"ttl":  c.ttl.String(),
+		},
+		"listCache": map[string]interface{}{
+			"size": c.listCache.ItemCount(),
+			"ttl":  c.listTTL.String(),
+		},
+	}
+}