ceremonyclient/go-libp2p-blossomsub/timecache/first_seen_cache.go

57 lines
902 B
Go
Raw Normal View History

package timecache
import (
"context"
"sync"
"time"
)
// FirstSeenCache is a time cache that only marks the expiry of a message when first added.
type FirstSeenCache struct {
lk sync.RWMutex
m map[string]time.Time
ttl time.Duration
done func()
}
var _ TimeCache = (*FirstSeenCache)(nil)
func newFirstSeenCache(ttl time.Duration) *FirstSeenCache {
tc := &FirstSeenCache{
m: make(map[string]time.Time),
ttl: ttl,
}
ctx, done := context.WithCancel(context.Background())
tc.done = done
go background(ctx, &tc.lk, tc.m)
return tc
}
func (tc *FirstSeenCache) Done() {
tc.done()
}
func (tc *FirstSeenCache) Has(s string) bool {
tc.lk.RLock()
defer tc.lk.RUnlock()
_, ok := tc.m[s]
return ok
}
func (tc *FirstSeenCache) Add(s string) bool {
tc.lk.Lock()
defer tc.lk.Unlock()
_, ok := tc.m[s]
if ok {
return false
}
tc.m[s] = time.Now().Add(tc.ttl)
return true
}