snapshot of https://github.com/casbin/casbin.git (master, 2026-09-15; blobs > 131072B omitted)

enforcer_cached.go

@@ -0,0 +1,188 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package casbin
+
+import (
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/casbin/casbin/v3/persist/cache"
+)
+
+// CachedEnforcer wraps Enforcer and provides decision cache.
+type CachedEnforcer struct {
+	*Enforcer
+	expireTime  time.Duration
+	cache       cache.Cache
+	enableCache int32
+	locker      *sync.RWMutex
+}
+
+type CacheableParam interface {
+	GetCacheKey() string
+}
+
+// NewCachedEnforcer creates a cached enforcer via file or DB.
+func NewCachedEnforcer(params ...interface{}) (*CachedEnforcer, error) {
+	e := &CachedEnforcer{}
+	var err error
+	e.Enforcer, err = NewEnforcer(params...)
+	if err != nil {
+		return nil, err
+	}
+
+	e.enableCache = 1
+	e.cache, _ = cache.NewDefaultCache()
+	e.locker = new(sync.RWMutex)
+	return e, nil
+}
+
+// EnableCache determines whether to enable cache on Enforce(). When enableCache is enabled, cached result (true | false) will be returned for previous decisions.
+func (e *CachedEnforcer) EnableCache(enableCache bool) {
+	var enabled int32
+	if enableCache {
+		enabled = 1
+	}
+	atomic.StoreInt32(&e.enableCache, enabled)
+}
+
+// Enforce decides whether a "subject" can access a "object" with the operation "action", input parameters are usually: (sub, obj, act).
+// if rvals is not string , ignore the cache.
+func (e *CachedEnforcer) Enforce(rvals ...interface{}) (bool, error) {
+	if atomic.LoadInt32(&e.enableCache) == 0 {
+		return e.Enforcer.Enforce(rvals...)
+	}
+
+	key, ok := e.getKey(rvals...)
+	if !ok {
+		return e.Enforcer.Enforce(rvals...)
+	}
+
+	if res, err := e.getCachedResult(key); err == nil {
+		return res, nil
+	} else if err != cache.ErrNoSuchKey {
+		return res, err
+	}
+
+	res, err := e.Enforcer.Enforce(rvals...)
+	if err != nil {
+		return false, err
+	}
+
+	err = e.setCachedResult(key, res, e.expireTime)
+	return res, err
+}
+
+func (e *CachedEnforcer) LoadPolicy() error {
+	if atomic.LoadInt32(&e.enableCache) != 0 {
+		if err := e.cache.Clear(); err != nil {
+			return err
+		}
+	}
+	return e.Enforcer.LoadPolicy()
+}
+
+func (e *CachedEnforcer) RemovePolicy(params ...interface{}) (bool, error) {
+	if atomic.LoadInt32(&e.enableCache) != 0 {
+		key, ok := e.getKey(params...)
+		if ok {
+			if err := e.cache.Delete(key); err != nil && err != cache.ErrNoSuchKey {
+				return false, err
+			}
+		}
+	}
+	return e.Enforcer.RemovePolicy(params...)
+}
+
+func (e *CachedEnforcer) RemovePolicies(rules [][]string) (bool, error) {
+	if len(rules) != 0 {
+		if atomic.LoadInt32(&e.enableCache) != 0 {
+			for _, rule := range rules {
+				irule := make([]interface{}, len(rule))
+				for i, param := range rule {
+					irule[i] = param
+				}
+				key, _ := e.getKey(irule...)
+				if err := e.cache.Delete(key); err != nil && err != cache.ErrNoSuchKey {
+					return false, err
+				}
+			}
+		}
+	}
+	return e.Enforcer.RemovePolicies(rules)
+}
+
+func (e *CachedEnforcer) getCachedResult(key string) (res bool, err error) {
+	e.locker.Lock()
+	defer e.locker.Unlock()
+	return e.cache.Get(key)
+}
+
+func (e *CachedEnforcer) SetExpireTime(expireTime time.Duration) {
+	e.expireTime = expireTime
+}
+
+func (e *CachedEnforcer) SetCache(c cache.Cache) {
+	e.cache = c
+}
+
+func (e *CachedEnforcer) setCachedResult(key string, res bool, extra ...interface{}) error {
+	e.locker.Lock()
+	defer e.locker.Unlock()
+	return e.cache.Set(key, res, extra...)
+}
+
+func (e *CachedEnforcer) getKey(params ...interface{}) (string, bool) {
+	return GetCacheKey(params...)
+}
+
+// InvalidateCache deletes all the existing cached decisions.
+func (e *CachedEnforcer) InvalidateCache() error {
+	e.locker.Lock()
+	defer e.locker.Unlock()
+	return e.cache.Clear()
+}
+
+func GetCacheKey(params ...interface{}) (string, bool) {
+	key := strings.Builder{}
+	for _, param := range params {
+		switch typedParam := param.(type) {
+		case string:
+			key.WriteString(typedParam)
+		case CacheableParam:
+			key.WriteString(typedParam.GetCacheKey())
+		default:
+			return "", false
+		}
+		key.WriteString("$$")
+	}
+	return key.String(), true
+}
+
+// ClearPolicy clears all policy.
+func (e *CachedEnforcer) ClearPolicy() {
+	if atomic.LoadInt32(&e.enableCache) != 0 {
+		if err := e.cache.Clear(); err != nil {
+			// Logger has been removed - error is ignored
+			return
+		}
+	}
+	e.Enforcer.ClearPolicy()
+}