mirror of https://github.com/hashicorp/consul
36 lines
730 B
Go
36 lines
730 B
Go
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// Copyright (c) HashiCorp, Inc.
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// SPDX-License-Identifier: BUSL-1.1
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package channels
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import "fmt"
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// DeliverLatest will drain the channel discarding any messages if there are any and sends the current message.
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func DeliverLatest[T any](val T, ch chan T) error {
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// Send if chan is empty
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select {
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case ch <- val:
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return nil
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default:
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}
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// If it falls through to here, the channel is not empty.
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// Drain the channel.
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done := false
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for !done {
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select {
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case <-ch:
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continue
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default:
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done = true
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}
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}
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// Attempt to send again. If it is not empty, throw an error
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select {
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case ch <- val:
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return nil
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default:
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return fmt.Errorf("failed to deliver latest event: chan full again after draining")
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}
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}
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