[#639] node: Refactor TTL cache

Migrate from internal to external TTL implementation

Signed-off-by: Alexander Chuprov <a.chuprov@yadro.com>
This commit is contained in:
Alexander Chuprov 2023-11-30 11:45:31 +03:00 committed by Evgenii Stratonikov
parent 26e4f7005c
commit 7f6852bbd2
2 changed files with 65 additions and 20 deletions

View file

@ -12,38 +12,29 @@ import (
cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
netmapSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
lru "github.com/hashicorp/golang-lru/v2"
"github.com/hashicorp/golang-lru/v2/expirable"
)
type netValueReader[K any, V any] func(K) (V, error)
type valueWithTime[V any] struct {
type valueWithError[V any] struct {
v V
t time.Time
// cached error in order to not repeat failed request for some time
e error
}
// entity that provides TTL cache interface.
type ttlNetCache[K comparable, V any] struct {
ttl time.Duration
sz int
cache *lru.Cache[K, *valueWithTime[V]]
cache *expirable.LRU[K, *valueWithError[V]]
netRdr netValueReader[K, V]
keyLocker *utilSync.KeyLocker[K]
}
// complicates netValueReader with TTL caching mechanism.
func newNetworkTTLCache[K comparable, V any](sz int, ttl time.Duration, netRdr netValueReader[K, V]) *ttlNetCache[K, V] {
cache, err := lru.New[K, *valueWithTime[V]](sz)
fatalOnErr(err)
cache := expirable.NewLRU[K, *valueWithError[V]](sz, nil, ttl)
return &ttlNetCache[K, V]{
ttl: ttl,
sz: sz,
cache: cache,
netRdr: netRdr,
keyLocker: utilSync.NewKeyLocker[K](),
@ -57,7 +48,7 @@ func newNetworkTTLCache[K comparable, V any](sz int, ttl time.Duration, netRdr n
// returned value should not be modified.
func (c *ttlNetCache[K, V]) get(key K) (V, error) {
val, ok := c.cache.Peek(key)
if ok && time.Since(val.t) < c.ttl {
if ok {
return val.v, val.e
}
@ -65,15 +56,14 @@ func (c *ttlNetCache[K, V]) get(key K) (V, error) {
defer c.keyLocker.Unlock(key)
val, ok = c.cache.Peek(key)
if ok && time.Since(val.t) < c.ttl {
if ok {
return val.v, val.e
}
v, err := c.netRdr(key)
c.cache.Add(key, &valueWithTime[V]{
c.cache.Add(key, &valueWithError[V]{
v: v,
t: time.Now(),
e: err,
})
@ -84,9 +74,8 @@ func (c *ttlNetCache[K, V]) set(k K, v V, e error) {
c.keyLocker.Lock(k)
defer c.keyLocker.Unlock(k)
c.cache.Add(k, &valueWithTime[V]{
c.cache.Add(k, &valueWithError[V]{
v: v,
t: time.Now(),
e: e,
})
}

View file

@ -0,0 +1,56 @@
package main
import (
"errors"
"testing"
"time"
"github.com/stretchr/testify/require"
)
func TestTTLNetCache(t *testing.T) {
ttlDuration := time.Millisecond * 50
cache := newNetworkTTLCache[string, time.Time](10, ttlDuration, testNetValueReader)
key := "key"
t.Run("Test Add and Get", func(t *testing.T) {
ti := time.Now()
cache.set(key, ti, nil)
val, err := cache.get(key)
require.NoError(t, err)
require.Equal(t, ti, val)
})
t.Run("Test TTL", func(t *testing.T) {
ti := time.Now()
cache.set(key, ti, nil)
time.Sleep(2 * ttlDuration)
val, err := cache.get(key)
require.NoError(t, err)
require.NotEqual(t, val, ti)
})
t.Run("Test Remove", func(t *testing.T) {
ti := time.Now()
cache.set(key, ti, nil)
cache.remove(key)
val, err := cache.get(key)
require.NoError(t, err)
require.NotEqual(t, val, ti)
})
t.Run("Test Cache Error", func(t *testing.T) {
cache.set("error", time.Now(), errors.New("mock error"))
_, err := cache.get("error")
require.Error(t, err)
require.Equal(t, "mock error", err.Error())
})
}
func testNetValueReader(key string) (time.Time, error) {
if key == "error" {
return time.Now(), errors.New("mock error")
}
return time.Now(), nil
}