43 lines
787 B
Go
43 lines
787 B
Go
package rate
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import (
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"context"
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"fmt"
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"sync"
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"time"
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)
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type Limiter struct {
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mu sync.Mutex
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lastReqTime time.Time
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interval time.Duration
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}
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func NewLimiter(interval time.Duration) *Limiter {
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return &Limiter{interval: interval}
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}
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// Wait enforces minimum spacing between upstream Jikan requests.
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func (l *Limiter) Wait(ctx context.Context) error {
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l.mu.Lock()
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defer l.mu.Unlock()
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now := time.Now()
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nextAllowed := l.lastReqTime.Add(l.interval)
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if now.Before(nextAllowed) {
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timer := time.NewTimer(nextAllowed.Sub(now))
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defer timer.Stop()
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select {
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case <-timer.C:
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case <-ctx.Done():
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return fmt.Errorf("request canceled while waiting for rate limit: %w", ctx.Err())
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}
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l.lastReqTime = time.Now()
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return nil
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}
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l.lastReqTime = now
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return nil
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}
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