41 lines
640 B
Go
41 lines
640 B
Go
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package helper
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import (
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"context"
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"io"
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)
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type ContextReader struct {
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ctx context.Context
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underlyingReader io.Reader
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}
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func NewContextReader(ctx context.Context, underlyingReader io.Reader) *ContextReader {
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return &ContextReader{
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ctx: ctx,
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underlyingReader: underlyingReader,
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}
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}
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func (r *ContextReader) Read(b []byte) (int, error) {
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if r.canceled() {
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return 0, r.err()
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}
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n, err := r.underlyingReader.Read(b)
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if r.canceled() {
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err = r.err()
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}
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return n, err
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}
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func (r *ContextReader) canceled() bool {
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return r.err() != nil
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}
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func (r *ContextReader) err() error {
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return r.ctx.Err()
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}
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