diff --git a/cache.go b/cache.go index c159a96..ce4d6e9 100644 --- a/cache.go +++ b/cache.go @@ -11,51 +11,113 @@ import ( ) var ( - ErrNotFound = errors.New("not found") + ErrNotFound = errors.New("not found") + OptWithoutGetter = optWithoutGetter{} // for get only + OptWithCreateTime = optWithCreateTime{} // for set & get ) type Cacher[T any] interface { - GetFromCache(id string) (dat *T, err error) - SetIntoCache(id string, dat *T) (err error) + GetFromCache(id string, options ...Option) (dat *T, err error) + SetIntoCache(id string, dat *T, options ...Option) (err error) } type Getter[T any] interface { GetById(id string) (dat *T, err error) } +type ( + Option any + optWithoutGetter struct{} // for get only + optWithCreateTime struct{ createtime *time.Time } // for set & get + Options struct { + withoutGetter *optWithoutGetter + withCreateTime *optWithCreateTime + } +) + +func optionParser(options ...Option) (opts Options, err error) { + var l = len(options) + if l == 0 { + return opts, nil + } + //TODO: add i out of range & options[i] type mismatch panic recover + for i := 0; i < l; i++ { + o := options[i] + switch o.(type) { + case optWithoutGetter: + opts.withoutGetter = new(optWithoutGetter) + case optWithCreateTime: + opts.withCreateTime = new(optWithCreateTime) + i++ + opts.withCreateTime.createtime = options[i].(*time.Time) + default: + panic("unreachable code, maybe miss some code modification") + } + } + return opts, nil +} + +func isOptWithCreateTimeForSetter(opts Options) bool { + if opts.withCreateTime == nil { + return false + } + var createtime = opts.withCreateTime.createtime + if createtime == nil { + return false + } + return !createtime.IsZero() +} + +func isOptWithCreateTimeForGetter(opts Options) bool { + if opts.withCreateTime == nil { + return false + } + var createtime = opts.withCreateTime.createtime + if createtime == nil { + return false + } + return createtime.IsZero() +} + type Config struct { - UseLocalCache bool - LocalCacheLifetimeSecond int64 - UseRedisCache bool - RedisCacheConn redis.Conn - RedisCacheKeyPrefix string - RedisCacheLifetimeSecond int64 + UseLocalCache bool // use localcache or not + LocalCacheLifetimeSecond int64 // local cache lifetime(t<0: forever; t=0: default; t>0: seconds) + UseRedisCache bool // use redis or not + RedisCacheConn redis.Conn // redis.Conn + RedisCacheKeyPrefix string // redis key prefix + RedisCacheLifetimeSecond int64 // redis cache lifetime(t<0: forever; t=0: default; t>0: seconds) + UseGetter bool // not used + GetterNoWarning bool // no warning if no getter } func NewCache[T any](getter Getter[T], cfg Config) Cacher[T] { var c = new(cacher[T]) // Getter + c.cfg = cfg c.getter = getter // Local cache if cfg.UseLocalCache { c.localCache = new(localCacher[T]) c.localCache.cacheItems = map[string]*cacheItem[T]{} - c.localCache.cacheSecond = time.Duration(cfg.LocalCacheLifetimeSecond) * time.Second - if c.localCache.cacheSecond.Nanoseconds() <= 0 { - c.localCache.cacheSecond = 60 * time.Second + c.localCache.cacheDuration = time.Duration(cfg.LocalCacheLifetimeSecond) * time.Second + if c.localCache.cacheDuration.Nanoseconds() == 0 { + c.localCache.cacheDuration = 60 * time.Second } } // Redis cache if cfg.UseRedisCache && cfg.RedisCacheConn != nil { - c.redisCache = new(redisCacher[T]) - c.redisCache.rds = cfg.RedisCacheConn - c.redisCache.cacheSecond = time.Duration(cfg.RedisCacheLifetimeSecond) * time.Second if cfg.RedisCacheKeyPrefix == "" { panic("redis cache's key prefix must not be null") } + c.redisCache = new(redisCacher[T]) + c.redisCache.rds = cfg.RedisCacheConn + c.redisCache.cacheDuration = time.Duration(cfg.RedisCacheLifetimeSecond) * time.Second c.redisCache.cachePrefix = fmt.Sprintf("%s-cache-id:", cfg.RedisCacheKeyPrefix) + if c.redisCache.cacheDuration.Nanoseconds() == 0 { + c.redisCache.cacheDuration = 180 * time.Second + } } else if cfg.UseRedisCache { panic("want to user redis cache, but redis.Conn is nil") } @@ -69,44 +131,60 @@ type cacheItem[T any] struct { } type localCacher[T any] struct { - cacheItems map[string]*cacheItem[T] - cacheSecond time.Duration + cacheItems map[string]*cacheItem[T] + cacheDuration time.Duration } type redisCacher[T any] struct { - rds redis.Conn - cachePrefix string - cacheSecond time.Duration + rds redis.Conn + cachePrefix string + cacheDuration time.Duration } type cacher[T any] struct { + cfg Config getter Getter[T] localCache *localCacher[T] redisCache *redisCacher[T] } -func (c *localCacher[T]) GetFromCache(id string) (t *T, err error) { - var earliestCreateTime = time.Now().Add(-c.cacheSecond) - if a, ok := c.cacheItems[id]; !ok { +func (c *localCacher[T]) GetFromCache(id string, options ...Option) (t *T, err error) { + var a, ok = c.cacheItems[id] + if !ok { return nil, ErrNotFound - } else if earliestCreateTime.Before(a.CreateTime) { - return a.Data, nil } - //TODO: cocurrent - delete(c.cacheItems, id) - return nil, ErrNotFound + + if c.cacheDuration.Nanoseconds() > 0 { + var earliestCreateTime = time.Now().Add(-c.cacheDuration) + if a.CreateTime.Before(earliestCreateTime) { + log.Infof("app(%s) is in redis cache but expired", id) + //TODO: cocurrent + delete(c.cacheItems, id) + return nil, ErrNotFound + } + } + + opt, err := optionParser(options...) + if err == nil && isOptWithCreateTimeForGetter(opt) { + *opt.withCreateTime.createtime = a.CreateTime + } + + return a.Data, nil } -func (c *localCacher[T]) SetIntoCache(id string, t *T) (err error) { - c.cacheItems[id] = &cacheItem[T]{ - Data: t, - CreateTime: time.Now(), +func (c *localCacher[T]) SetIntoCache(id string, t *T, options ...Option) (err error) { + var newitem = &cacheItem[T]{Data: t} + opt, err := optionParser(options...) + if err == nil && isOptWithCreateTimeForSetter(opt) { + newitem.CreateTime = *opt.withCreateTime.createtime + } else { + newitem.CreateTime = time.Now() } - fmt.Println("cacheItems", c.cacheItems) + c.cacheItems[id] = newitem return nil } -func (c *redisCacher[T]) GetFromCache(id string) (*T, error) { +func (c *redisCacher[T]) GetFromCache(id string, options ...Option) (*T, error) { var ( rds = c.rds redisKey = c.cachePrefix + id @@ -128,34 +206,45 @@ func (c *redisCacher[T]) GetFromCache(id string) (*T, error) { } // Step 3. check expire time - var d = c.cacheSecond - if d.Nanoseconds() > 0 { - var earliestCreateTime = time.Now().Add(-c.cacheSecond) + if c.cacheDuration.Nanoseconds() > 0 { + var earliestCreateTime = time.Now().Add(-c.cacheDuration) if a.CreateTime.Before(earliestCreateTime) { log.Infof("app(%s) is in redis cache but expired", id) return nil, ErrNotFound } } + // Step 4. get cache creattime if need + opt, err := optionParser(options...) + if err == nil && isOptWithCreateTimeForGetter(opt) { + *opt.withCreateTime.createtime = a.CreateTime + } + return a.Data, nil } -func (c *redisCacher[T]) SetIntoCache(id string, t *T) error { +func (c *redisCacher[T]) SetIntoCache(id string, t *T, options ...Option) error { var ( + opt, _ = optionParser(options...) rds = c.rds redisKey = c.cachePrefix + id redisValue = []byte{} err error = nil ) - // Step 1. decode from string - var a = cacheItem[T]{Data: t, CreateTime: time.Now()} + // Step 1. encode to string + var a = cacheItem[T]{Data: t} + if err == nil && isOptWithCreateTimeForSetter(opt) { + a.CreateTime = *opt.withCreateTime.createtime + } else { + a.CreateTime = time.Now() + } if redisValue, err = json.Marshal(a); err != nil { log.Errorf("set cache failed: 'json marshal failed <%s>'", err.Error()) return errors.New("set cache failed: 'marshal failed'") } - // Step 2. read from redis + // Step 2. write into redis if _, err = rds.Do("SET", redisKey, string(redisValue)); err != nil { log.Errorf("set cache failed: 'redis failed <%s>'", err.Error()) return errors.New("set cache failed: 'redis failed'") @@ -164,45 +253,53 @@ func (c *redisCacher[T]) SetIntoCache(id string, t *T) error { return nil } -func (c *cacher[T]) GetFromCache(id string) (dat *T, err error) { +func (c *cacher[T]) GetFromCache(id string, options ...Option) (dat *T, err error) { // Step 1. check id - if len(id) < 8 { + if len(id) < 1 { return nil, ErrNotFound } + var opt, _ = optionParser(options...) // Step 2. get from [local] if c.localCache != nil { - if dat, err := c.localCache.GetFromCache(id); err == nil { + if dat, err := c.localCache.GetFromCache(id, options...); err == nil { log.Infof("get cache(id:%s) from localCacher success", id) return dat, nil - } else { - log.Infof("get cache(id:%s) from localCacher failed, try next", id) } + log.Infof("get cache(id:%s) from localCacher failed, try next", id) } // Step 3. get from [redis] if c.redisCache != nil { - if dat, err := c.redisCache.GetFromCache(id); err == nil { + if opt.withCreateTime == nil { //get create time from redis + options = append(options, OptWithCreateTime, new(time.Time)) + } + if dat, err := c.redisCache.GetFromCache(id, options...); err == nil { if c.localCache != nil { - log.Infof("set cache(id:%s) to localCache by redisCacher") - c.localCache.SetIntoCache(id, dat) + c.localCache.SetIntoCache(id, dat, options...) //set create time from redis + log.Infof("set cache(id:%s) to localCache by redisCacher done", id) } log.Infof("get cache(id:%s) from redisCacher success", id) return dat, nil - } else if c.getter == nil { - log.Warningf("get cache(id:%s) from all cache failed, and storager is nil, "+ - "trade as not found. may be you forgot set in db ???", id) - return nil, ErrNotFound } + log.Infof("get cache(id:%s) from redisCacher failed, try next", id) } - if c.getter == nil { - log.Warningf("get cache(id:%s) from all cache failed, and storager is nil, "+ - "trade as not found. may be you forgot set in db ???", id) + + var getter = c.getter + if opt.withoutGetter != nil { + log.Infof("all cache failed, and option 'withnogetter' is set, return ErrNotFound") + return nil, ErrNotFound + } + if getter == nil { + log.Infof("all cache failed, and getter is nil, return ErrNotFound") + if c.cfg.GetterNoWarning == false { + log.Warningf("cache 'getter' is nil, did you save right config in database?") + } return nil, ErrNotFound } // Step 4. get from [storager(database or somewhere)] - dat, err = c.getter.GetById(id) + dat, err = getter.GetById(id) if err != nil { log.Errorf("cache(id:%s) is not in database, something error: %s", id, err) return nil, ErrNotFound @@ -211,10 +308,10 @@ func (c *cacher[T]) GetFromCache(id string) (dat *T, err error) { // Step 5. set to cacha if c.localCache != nil { - c.localCache.SetIntoCache(id, dat) + c.localCache.SetIntoCache(id, dat, options...) } if c.redisCache != nil { - c.redisCache.SetIntoCache(id, dat) + c.redisCache.SetIntoCache(id, dat, options...) } // Step 6. return @@ -222,10 +319,10 @@ func (c *cacher[T]) GetFromCache(id string) (dat *T, err error) { return dat, nil } -func (c *cacher[T]) SetIntoCache(id string, dat *T) (err error) { +func (c *cacher[T]) SetIntoCache(id string, dat *T, options ...Option) (err error) { // localCache if c.localCache != nil { - if err = c.localCache.SetIntoCache(id, dat); err != nil { + if err = c.localCache.SetIntoCache(id, dat, options...); err != nil { log.Infof("set data into localCache failed, err:%s", err) } else { log.Debugf("success set data into localCache, id: %s", id) @@ -234,7 +331,7 @@ func (c *cacher[T]) SetIntoCache(id string, dat *T) (err error) { // redisCache if c.redisCache != nil { - if err = c.redisCache.SetIntoCache(id, dat); err != nil { + if err = c.redisCache.SetIntoCache(id, dat, options...); err != nil { log.Infof("set data into redisCache failed, err:%s", err) } else { log.Debugf("success set data into redisCache, id: %s", id)