Spaces:
Paused
Paused
File size: 1,846 Bytes
4ac9af9 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 | package helps
import (
"crypto/sha256"
"encoding/hex"
"sync"
"time"
)
type userIDCacheEntry struct {
value string
expire time.Time
}
var (
userIDCache = make(map[string]userIDCacheEntry)
userIDCacheMu sync.RWMutex
userIDCacheCleanupOnce sync.Once
)
const (
userIDTTL = time.Hour
userIDCacheCleanupPeriod = 15 * time.Minute
)
func startUserIDCacheCleanup() {
go func() {
ticker := time.NewTicker(userIDCacheCleanupPeriod)
defer ticker.Stop()
for range ticker.C {
purgeExpiredUserIDs()
}
}()
}
func purgeExpiredUserIDs() {
now := time.Now()
userIDCacheMu.Lock()
for key, entry := range userIDCache {
if !entry.expire.After(now) {
delete(userIDCache, key)
}
}
userIDCacheMu.Unlock()
}
func userIDCacheKey(apiKey string) string {
sum := sha256.Sum256([]byte(apiKey))
return hex.EncodeToString(sum[:])
}
func CachedUserID(apiKey string) string {
if apiKey == "" {
return generateFakeUserID()
}
userIDCacheCleanupOnce.Do(startUserIDCacheCleanup)
key := userIDCacheKey(apiKey)
now := time.Now()
userIDCacheMu.RLock()
entry, ok := userIDCache[key]
valid := ok && entry.value != "" && entry.expire.After(now) && isValidUserID(entry.value)
userIDCacheMu.RUnlock()
if valid {
userIDCacheMu.Lock()
entry = userIDCache[key]
if entry.value != "" && entry.expire.After(now) && isValidUserID(entry.value) {
entry.expire = now.Add(userIDTTL)
userIDCache[key] = entry
userIDCacheMu.Unlock()
return entry.value
}
userIDCacheMu.Unlock()
}
newID := generateFakeUserID()
userIDCacheMu.Lock()
entry, ok = userIDCache[key]
if !ok || entry.value == "" || !entry.expire.After(now) || !isValidUserID(entry.value) {
entry.value = newID
}
entry.expire = now.Add(userIDTTL)
userIDCache[key] = entry
userIDCacheMu.Unlock()
return entry.value
}
|