56 lines
1.3 KiB
Go
56 lines
1.3 KiB
Go
// Package freq keeps track of last X seen events. The events themselves are not stored
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// here. So the Freq type should be added next to the thing it is tracking.
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package freq
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import (
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"sync"
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"time"
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)
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// Freq tracks the frequencies of things.
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type Freq struct {
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// Last time we saw a query for this element.
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last time.Time
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// Number of this in the last time slice.
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hits int
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sync.RWMutex
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}
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// New returns a new initialized Freq.
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func New(t time.Time) *Freq {
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return &Freq{last: t, hits: 0}
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}
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// Update updates the number of hits. Last time seen will be set to now.
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// If the last time we've seen this entity is within now - d, we increment hits, otherwise
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// we reset hits to 1. It returns the number of hits.
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func (f *Freq) Update(d time.Duration, now time.Time) int {
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earliest := now.Add(-1 * d)
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f.Lock()
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defer f.Unlock()
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if f.last.Before(earliest) {
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f.last = now
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f.hits = 1
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return f.hits
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}
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f.last = now
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f.hits++
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return f.hits
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}
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// Hits returns the number of hits that we have seen, according to the updates we have done to f.
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func (f *Freq) Hits() int {
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f.RLock()
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defer f.RUnlock()
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return f.hits
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}
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// Reset resets f to time t and hits to hits.
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func (f *Freq) Reset(t time.Time, hits int) {
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f.Lock()
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defer f.Unlock()
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f.last = t
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f.hits = hits
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}
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