Libcache
A Lightweight in-memory key:value cache library for Go.
Introduction
Caches are tremendously useful in a wide variety of use cases.
you should consider using caches when a value is expensive to compute or retrieve,
and you will need its value on a certain input more than once.
libcache is here to help with that.
Libcache are local to a single run of your application.
They do not store data in files, or on outside servers.
Libcache previously an go-guardian package and designed to be a companion with it.
While both can operate completely independently.
Features
- Rich caching API
- Maximum cache size enforcement
- Default cache TTL (time-to-live) as well as custom TTLs per cache entry
- Thread safe as well as non-thread safe
- Event-Driven callbacks (Notify)
- Dynamic cache creation
- Multiple cache replacement policies:
- FIFO (First In, First Out)
- LIFO (Last In, First Out)
- LRU (Least Recently Used)
- MRU (Most Recently Used)
- LFU (Least Frequently Used)
- ARC (Adaptive Replacement Cache)
Quickstart
Installing
Using libcache is easy. First, use go get to install the latest version of the library.
Next, include libcache in your application:
_ "github.com/shaj13/libcache/
"github.com/shaj13/libcache"
)
Examples
Note: All examples use the LRU cache replacement policy for simplicity, any other cache replacement policy can be applied to them.
Basic
import (
"fmt"
"github.com/shaj13/libcache"
_ "github.com/shaj13/libcache/lru"
)
func main() {
size := 10
cache := libcache.LRU.NewUnsafe(size)
for i:= 0 ; i < 10 ; i++ {
cache.Store(i, i)
}
fmt.Println(cache.Load(0)) // nil, false
fmt.Println(cache.Load(1)) // 1, true
}
Thread Safe
import (
"fmt"
"github.com/shaj13/libcache"
_ "github.com/shaj13/libcache/lru"
)
func main() {
done := make(chan struct{})
f := func(c libcache.Cache) {
for !c.Contains(5) {
}
fmt.Println(c.Load(5)) // 5, true
done <- struct{}{}
}
size := 10
cache := libcache.LRU.New(size)
go f(cache)
for i := 0; i < 10; i++ {
cache.Store(i, i)
}
<-done
}
Unlimited Size
zero capacity means cache has no limit and replacement policy turned off.
import (
"fmt"
"github.com/shaj13/libcache"
_ "github.com/shaj13/libcache/lru"
)
func main() {
cache := libcache.LRU.New(0)
for i:= 0 ; i < 100000 ; i++ {
cache.Store(i, i)
}
fmt.Println(cache.Load(55555))
}
TTL
import (
"fmt"
"time"
"github.com/shaj13/libcache"
_ "github.com/shaj13/libcache/lru"
)
func main() {
cache := libcache.LRU.New(10)
cache.SetTTL(time.Second) // default TTL
for i:= 0 ; i < 10 ; i++ {
cache.Store(i, i)
}
fmt.Println(cache.Expiry(1))
cache.StoreWithTTL("mykey", "value", time.Hour) // TTL per cache entry
fmt.Println(cache.Expiry("mykey"))
}
Events
import (
"fmt"
"time"
"github.com/shaj13/libcache"
_ "github.com/shaj13/libcache/lru"
)
func main() {
cache := libcache.LRU.New(10)
eventc := make(chan libcache.Event, 10)
cache.Notify(eventc)
defer cache.Ignore(eventc)
go func() {
for {
e := <-eventc
fmt.Printf("Operation %s on Key %v \n", e.Op, e.Key)
}
}()
cache.Load(1)
cache.Store(1, 1)
cache.Peek(1)
cache.Delete(1)
}
GC
import (
"fmt"
"time"
"github.com/shaj13/libcache"
_ "github.com/shaj13/libcache/lru"
)
func main() {
cache := libcache.LRU.New(10)
eventc := make(chan libcache.Event, 10)
cache.Notify(eventc)
defer cache.Ignore(eventc)
go func() {
for {
e := <-eventc
fmt.Printf("Operation %s on Key %v \n", e.Op, e.Key)
}
}()
ctx, cacnel := context.WithTimeout(context.Background(), time.Second*2)
defer cacnel()
cache.StoreWithTTL(1, 1, time.Second)
// GC is a long running function, evict expired items from the cache on time.
libcache.GC(ctx, cache)
cache.StoreWithTTL(1, 1, time.Second)
time.Sleep(time.Second)
// Runs a garbage collection and blocks the caller until the garbage collection is complete
cache.GC()
}
Contributing
- Fork it
- Download your fork to your PC (
git clone https://github.com/your_username/libcache && cd libcache) - Create your feature branch (
git checkout -b my-new-feature) - Make changes and add them (
git add .) - Commit your changes (
git commit -m 'Add some feature') - Push to the branch (
git push origin my-new-feature) - Create new pull request
License
Libcache is released under the MIT license. See LICENSE