LRUCache is an LRU cache written in Go. The cache supports TTL background cleaning.
The LRUCache is thread-safe
Use a go-get tool (or any go-compatible package manager) to download the cache:
go get github.com/alexions/go-lru-ttl-cacheImport the cache in your go file:
import (
lrucache "github.com/alexions/go-lru-ttl-cache"
)
It is highly recommended to use tags to lock the cache version for your project.
Import and create a Cache instance:
var cache = lrucache.NewLRUCache(lrucache.Configuration())
Configure allows you to configure cache using chainable API:
var cache = lrucache.NewLRUCache(
lrucache.Configuration().
SetDefaultTTL(5 * time.Minute).
SetMaxSize(100)
)
Possible configuration with default values:
SetDefaultTTL(ttl time.Duration)- default expiration TTL. Item will be removed after the specified time (default: -1, no expiration)SetMaxSize(size int)- cache storage limitation. After exceeding the limit the LRU item will be removed (default: math.MaxInt32 - 1)SetCleanupInterval(interval time.Duration)- the cleaning interval. All the items with expired TTL will be removed from the cache. Works only with DefaultTTL greater than 0 (default: run every 1 min)SetDeleteCallback(callback func(count int64))- callback function to get amount of removed items. Runs everyCleanup interval.
config := Configuration()
cache := NewLRUCache(config)
cache.Set("hello", "world")
value := cache.Get("hello")
fmt.Println(value) // "hello"
Any data can be stored
type User struct {
login string
pass string
}
config := Configuration()
cache := NewLRUCache(config)
cache.Set(1, &User{login: "alexions", pass: "password"})
user := cache.Get(1)
fmt.Println(user.(*User).login)
Checks if item is set:
if _, found := cache.Get("my_item"); !found {
// Item not found
}
config := Configuration().
SetCleanupInterval(10 * time.Millisecond).
SetDefaultTTL(25)
cache := NewLRUCache(config)
cache.Set("remove_by_ttl", 1)
cache.Set("keep_by_ttl", 2)
<-time.After(15 * time.Millisecond)
_, ok := cache.Get("remove_by_ttl") // ok is false, not found
_, ok = cache.Get("keep_by_ttl") // ok is true, found
fmt.Println(ok)
<-time.After(15 * time.Millisecond)
fmt.Println(cache.Size()) // will be 0
config := Configuration()
cache := NewLRUCache(config)
cache.Set(1, "hello")
cache.Set(2, "world")
fmt.Println(cache.Size()) // 2
config := Configuration()
cache := NewLRUCache(config)
cache.Set(1, "hello")
cache.Size() // 1
cache.Delete(1)
cache.Size() // 0
config := Configuration()
cache := NewLRUCache(config)
cache.Set(1, "hello")
cache.Set(2, "world")
cache.Size() // 2
cache.Clean()
cache.Size() // 0