Cache name	Constructor	Defaults	Description
LruCache	lcw.NewLruCache	keys=1000	LRU cache with limits
ExpirableCache	lcw.NewExpirableCache	keys=1000, ttl=5m	TTL cache with limits
Nop	lcw.NewNopCache		Do-nothing cache

Main features:

LoadingCache (guava style)
Limit maximum cache size (in bytes)
Limit maximum key size
Limit maximum size of a value
Limit number of keys
TTL support (ExpirableCache only)
Functional style invalidation
Functional options
Sane defaults

Install and update

go get -u github.com/go-pkgz/lcw

Usage

cache := lcw.NewLruCache(lcw.MaxKeys(500), lcw.MaxCacheSize(65536), lcw.MaxValSize(200), lcw.MaxKeySize(32))

val, err := cache.Get("key123", func() (lcw.Value, error) {
    res, err := getDataFromSomeSource(params) // returns string
    return res, err
})

if err != nil {
    panic("failed to get data")
}

s := val.(string) // cached value

Details

All byte-size limits (MaxCacheSize and MaxValSize) only work for values implementing lcw.Sizer interface.
Negative limits (max options) rejected
lgr.Value wraps interface{} and should be converted back to the concrete type.
The implementation started as a part of remark42 and later on moved to go-pkgz/rest library and finaly generalized to become lcw.