59 lines
942 B
Go
59 lines
942 B
Go
package timecache
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import (
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"context"
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"sync"
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"time"
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)
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// LastSeenCache is a time cache that extends the expiry of a seen message when added
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// or checked for presence with Has..
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type LastSeenCache struct {
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lk sync.Mutex
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m map[string]time.Time
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ttl time.Duration
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done func()
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}
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var _ TimeCache = (*LastSeenCache)(nil)
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func newLastSeenCache(ttl time.Duration) *LastSeenCache {
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tc := &LastSeenCache{
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m: make(map[string]time.Time),
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ttl: ttl,
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}
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ctx, done := context.WithCancel(context.Background())
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tc.done = done
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go background(ctx, &tc.lk, tc.m)
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return tc
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}
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func (tc *LastSeenCache) Done() {
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tc.done()
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}
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func (tc *LastSeenCache) Add(s string) bool {
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tc.lk.Lock()
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defer tc.lk.Unlock()
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_, ok := tc.m[s]
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tc.m[s] = time.Now().Add(tc.ttl)
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return !ok
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}
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func (tc *LastSeenCache) Has(s string) bool {
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tc.lk.Lock()
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defer tc.lk.Unlock()
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_, ok := tc.m[s]
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if ok {
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tc.m[s] = time.Now().Add(tc.ttl)
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}
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return ok
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}
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