telegraf/plugins/processors/ifname/ttl_cache.go

53 lines
903 B
Go

package ifname
import (
"time"
)
type TTLValType struct {
time time.Time // when entry was added
val valType
}
type timeFunc func() time.Time
type TTLCache struct {
validDuration time.Duration
lru LRUCache
now timeFunc
}
func NewTTLCache(valid time.Duration, capacity uint) TTLCache {
return TTLCache{
lru: NewLRUCache(capacity),
validDuration: valid,
now: time.Now,
}
}
func (c *TTLCache) Get(key keyType) (valType, bool, time.Duration) {
v, ok := c.lru.Get(key)
if !ok {
return valType{}, false, 0
}
age := c.now().Sub(v.time)
if age < c.validDuration {
return v.val, ok, age
} else {
c.lru.Delete(key)
return valType{}, false, 0
}
}
func (c *TTLCache) Put(key keyType, value valType) {
v := TTLValType{
val: value,
time: c.now(),
}
c.lru.Put(key, v)
}
func (c *TTLCache) Delete(key keyType) {
c.lru.Delete(key)
}