52 lines
967 B
Go
52 lines
967 B
Go
package backoff
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import (
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"context"
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"sync"
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)
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// NullPolicy does not do any backoff. It allows the caller
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// to execute the desired code once, and no more
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type NullPolicy struct{}
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func NewNull() *NullPolicy {
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return &NullPolicy{}
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}
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func (p *NullPolicy) Start(ctx context.Context) Controller {
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return newNullController(ctx)
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}
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type nullController struct {
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mu *sync.RWMutex
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ctx context.Context
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next chan struct{}
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}
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func newNullController(ctx context.Context) *nullController {
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cctx, cancel := context.WithCancel(ctx)
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c := &nullController{
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mu: &sync.RWMutex{},
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ctx: cctx,
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next: make(chan struct{}), // NO BUFFER
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}
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go func(ch chan struct{}, cancel func()) {
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ch <- struct{}{}
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close(ch)
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cancel()
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}(c.next, cancel)
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return c
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}
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func (c *nullController) Done() <-chan struct{} {
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c.mu.RLock()
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defer c.mu.RUnlock()
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return c.ctx.Done()
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}
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func (c *nullController) Next() <-chan struct{} {
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c.mu.RLock()
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defer c.mu.RUnlock()
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return c.next
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}
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