56 lines
874 B
Go
56 lines
874 B
Go
package main
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import (
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"sync"
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"time"
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)
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type fingerprint string
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type cachedAlert struct {
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expires time.Time
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}
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type cache struct {
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mu sync.Mutex
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duration time.Duration
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alerts map[fingerprint]*cachedAlert
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}
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func (a *cachedAlert) expired() bool {
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return a.expires.Before(time.Now())
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}
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func newCache(d time.Duration) *cache {
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c := new(cache)
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c.duration = d
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c.alerts = make(map[fingerprint]*cachedAlert)
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return c
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}
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func (c *cache) cleanup() {
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c.mu.Lock()
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defer c.mu.Unlock()
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for key, value := range c.alerts {
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if value.expired() {
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delete(c.alerts, key)
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}
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}
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}
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func (c *cache) set(f fingerprint) {
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c.mu.Lock()
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defer c.mu.Unlock()
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alert := new(cachedAlert)
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alert.expires = time.Now().Add(c.duration)
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c.alerts[f] = alert
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}
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func (c *cache) contains(f fingerprint) bool {
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c.mu.Lock()
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defer c.mu.Unlock()
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_, ok := c.alerts[f]
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return ok
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}
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