justxuewei commented on code in PR #2371: URL: https://github.com/apache/dubbo-go/pull/2371#discussion_r1288416835
########## registry/servicediscovery/store/cache_manager.go: ########## @@ -0,0 +1,178 @@ +/* + * 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 store + +import ( + "encoding/gob" + "os" + "sync" + "time" +) + +import ( + "github.com/dubbogo/gost/log/logger" + + "github.com/hashicorp/golang-lru" +) + +type CacheManager struct { + name string // The name of the cache manager + cacheFile string // The file path where the cache is stored + cacheExpired time.Duration // The duration after which the cache expires + stop chan struct{} // Channel used to stop the cache expiration routine + cache *lru.Cache // The LRU cache implementation + lock sync.Mutex +} + +type Item struct { + Key string + Value interface{} +} + +// NewCacheManager creates a new CacheManager instance. +// It initializes the cache manager with the provided parameters and starts a routine for cache expiration. +func NewCacheManager(name, cacheFile string, cacheExpired time.Duration, maxCacheSize int) (*CacheManager, error) { + cm := &CacheManager{ + name: name, + cacheFile: cacheFile, + cacheExpired: cacheExpired, + stop: make(chan struct{}), + } + cm.cache, _ = lru.New(maxCacheSize) + + // Check if the cache file exists and load the cache if it does + if _, err := os.Stat(cacheFile); err == nil { + if err = cm.loadCache(); err != nil { + logger.Warnf("Failed to load the cache file:[%s].The err is %v", cm.cacheFile, err) + } + } + go cm.RunDumpTask() + + return cm, nil +} + +// Get retrieves the value associated with the given key from the cache. +func (cm *CacheManager) Get(key string) (interface{}, bool) { + return cm.cache.Get(key) +} + +// Set sets the value associated with the given key in the cache. +func (cm *CacheManager) Set(key string, value interface{}) { + cm.cache.Add(key, value) +} + +// Delete removes the value associated with the given key from the cache. +func (cm *CacheManager) Delete(key string) { + cm.cache.Remove(key) +} + +// GetAll returns all the key-value pairs in the cache. +func (cm *CacheManager) GetAll() map[string]interface{} { + keys := cm.cache.Keys() + + result := make(map[string]interface{}) + for _, k := range keys { + result[k.(string)], _ = cm.cache.Get(k) + } + + return result +} + +// loadCache loads the cache from the cache file. +func (cm *CacheManager) loadCache() error { + cf, err := os.Open(cm.cacheFile) + if err != nil { + return err + } + + decoder := gob.NewDecoder(cf) + for { + var it Item + err = decoder.Decode(&it) + if err != nil { + if err.Error() == "EOF" { + break // Reached end of file + } + return err + } + // Add the loaded keys to the front of the LRU list + cm.cache.Add(it.Key, it.Value) + } + + return cf.Close() +} + +// dumpCache dumps the cache to the cache file. +func (cm *CacheManager) dumpCache() error { + + cm.lock.Lock() + defer cm.lock.Unlock() + + items := cm.GetAll() + + file, err := os.Create(cm.cacheFile) + if err != nil { + return err + } + + encoder := gob.NewEncoder(file) + for k, v := range items { + gob.Register(v) + err = encoder.Encode(&Item{ + Key: k, + Value: v, + }) + if err != nil { + return err + } + } + return file.Close() + +} + +func (cm *CacheManager) RunDumpTask() { + ticker := time.NewTicker(cm.cacheExpired) + for { + select { + case <-ticker.C: + // Dump the cache to the file + if err := cm.dumpCache(); err != nil { + // Handle error + logger.Warnf("Failed to dump cache,the err is %v", err) + } else { + logger.Infof("Dumping [%s] caches, latest entries %d", cm.name, cm.cache.Len()) + } + case <-cm.stop: + ticker.Stop() + return + } + } +} Review Comment: IIUR, you want to save the data to a file over a period of time. Then, `cacheExpired` is a confused name for me. Some names, like `dumpInterval`, are better than the current name. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: notifications-unsubscr...@dubbo.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: notifications-unsubscr...@dubbo.apache.org For additional commands, e-mail: notifications-h...@dubbo.apache.org
