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-rw-r--r--vendor/golang.org/x/time/rate/sometimes.go67
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diff --git a/vendor/golang.org/x/time/rate/sometimes.go b/vendor/golang.org/x/time/rate/sometimes.go
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+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package rate
+
+import (
+ "sync"
+ "time"
+)
+
+// Sometimes will perform an action occasionally. The First, Every, and
+// Interval fields govern the behavior of Do, which performs the action.
+// A zero Sometimes value will perform an action exactly once.
+//
+// # Example: logging with rate limiting
+//
+// var sometimes = rate.Sometimes{First: 3, Interval: 10*time.Second}
+// func Spammy() {
+// sometimes.Do(func() { log.Info("here I am!") })
+// }
+type Sometimes struct {
+ First int // if non-zero, the first N calls to Do will run f.
+ Every int // if non-zero, every Nth call to Do will run f.
+ Interval time.Duration // if non-zero and Interval has elapsed since f's last run, Do will run f.
+
+ mu sync.Mutex
+ count int // number of Do calls
+ last time.Time // last time f was run
+}
+
+// Do runs the function f as allowed by First, Every, and Interval.
+//
+// The model is a union (not intersection) of filters. The first call to Do
+// always runs f. Subsequent calls to Do run f if allowed by First or Every or
+// Interval.
+//
+// A non-zero First:N causes the first N Do(f) calls to run f.
+//
+// A non-zero Every:M causes every Mth Do(f) call, starting with the first, to
+// run f.
+//
+// A non-zero Interval causes Do(f) to run f if Interval has elapsed since
+// Do last ran f.
+//
+// Specifying multiple filters produces the union of these execution streams.
+// For example, specifying both First:N and Every:M causes the first N Do(f)
+// calls and every Mth Do(f) call, starting with the first, to run f. See
+// Examples for more.
+//
+// If Do is called multiple times simultaneously, the calls will block and run
+// serially. Therefore, Do is intended for lightweight operations.
+//
+// Because a call to Do may block until f returns, if f causes Do to be called,
+// it will deadlock.
+func (s *Sometimes) Do(f func()) {
+ s.mu.Lock()
+ defer s.mu.Unlock()
+ if s.count == 0 ||
+ (s.First > 0 && s.count < s.First) ||
+ (s.Every > 0 && s.count%s.Every == 0) ||
+ (s.Interval > 0 && time.Since(s.last) >= s.Interval) {
+ f()
+ s.last = time.Now()
+ }
+ s.count++
+}