60 lines
1.6 KiB
Go
60 lines
1.6 KiB
Go
/*
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Copyright 2019 The Kubernetes Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package parallelize
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import "context"
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// ErrorChannel supports non-blocking send and receive operation to capture error.
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// A maximum of one error is kept in the channel and the rest of the errors sent
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// are ignored, unless the existing error is received and the channel becomes empty
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// again.
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type ErrorChannel struct {
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errCh chan error
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}
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// SendError sends an error without blocking the sender.
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func (e *ErrorChannel) SendError(err error) {
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select {
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case e.errCh <- err:
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default:
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}
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}
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// SendErrorWithCancel sends an error without blocking the sender and calls
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// cancel function.
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func (e *ErrorChannel) SendErrorWithCancel(err error, cancel context.CancelFunc) {
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e.SendError(err)
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cancel()
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}
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// ReceiveError receives an error from channel without blocking on the receiver.
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func (e *ErrorChannel) ReceiveError() error {
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select {
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case err := <-e.errCh:
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return err
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default:
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return nil
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}
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}
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// NewErrorChannel returns a new ErrorChannel.
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func NewErrorChannel() *ErrorChannel {
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return &ErrorChannel{
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errCh: make(chan error, 1),
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}
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}
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