Files
beszel-ipv6/internal/hub/expirymap/expirymap.go

128 lines
2.8 KiB
Go

// Package expirymap provides a thread-safe map with expiring entries.
// It supports TTL-based expiration with both lazy cleanup on access
// and periodic background cleanup.
package expirymap
import (
"sync"
"time"
"github.com/pocketbase/pocketbase/tools/store"
)
type val[T comparable] struct {
value T
expires time.Time
}
type ExpiryMap[T comparable] struct {
store *store.Store[string, val[T]]
stopChan chan struct{}
stopOnce sync.Once
}
// New creates a new expiry map with custom cleanup interval
func New[T comparable](cleanupInterval time.Duration) *ExpiryMap[T] {
m := &ExpiryMap[T]{
store: store.New(map[string]val[T]{}),
stopChan: make(chan struct{}),
}
go m.startCleaner(cleanupInterval)
return m
}
// Set stores a value with the given TTL
func (m *ExpiryMap[T]) Set(key string, value T, ttl time.Duration) {
m.store.Set(key, val[T]{
value: value,
expires: time.Now().Add(ttl),
})
}
// GetOk retrieves a value and checks if it exists and hasn't expired
// Performs lazy cleanup of expired entries on access
func (m *ExpiryMap[T]) GetOk(key string) (T, bool) {
value, ok := m.store.GetOk(key)
if !ok {
return *new(T), false
}
// Check if expired and perform lazy cleanup
if value.expires.Before(time.Now()) {
m.store.Remove(key)
return *new(T), false
}
return value.value, true
}
// GetByValue retrieves a value by value
func (m *ExpiryMap[T]) GetByValue(val T) (key string, value T, ok bool) {
for key, v := range m.store.GetAll() {
if v.value == val {
// check if expired
if v.expires.Before(time.Now()) {
m.store.Remove(key)
break
}
return key, v.value, true
}
}
return "", *new(T), false
}
// Remove explicitly removes a key
func (m *ExpiryMap[T]) Remove(key string) {
m.store.Remove(key)
}
// RemovebyValue removes a value by value
func (m *ExpiryMap[T]) RemovebyValue(value T) (T, bool) {
for key, val := range m.store.GetAll() {
if val.value == value {
m.store.Remove(key)
return val.value, true
}
}
return *new(T), false
}
// startCleaner runs the background cleanup process
func (m *ExpiryMap[T]) startCleaner(interval time.Duration) {
tick := time.Tick(interval)
for {
select {
case <-tick:
m.cleanup()
case <-m.stopChan:
return
}
}
}
// StopCleaner stops the background cleanup process
func (m *ExpiryMap[T]) StopCleaner() {
m.stopOnce.Do(func() {
close(m.stopChan)
})
}
// cleanup removes all expired entries
func (m *ExpiryMap[T]) cleanup() {
now := time.Now()
for key, val := range m.store.GetAll() {
if val.expires.Before(now) {
m.store.Remove(key)
}
}
}
// UpdateExpiration updates the expiration time of a key
func (m *ExpiryMap[T]) UpdateExpiration(key string, ttl time.Duration) {
value, ok := m.store.GetOk(key)
if ok {
value.expires = time.Now().Add(ttl)
m.store.Set(key, value)
}
}