53 lines
971 B
Go
53 lines
971 B
Go
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package transformer
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import (
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"context"
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"io"
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)
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type writer interface {
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Write(ctx context.Context, p []byte) (n int, err error)
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}
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type multiWriter struct {
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writers []writer
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}
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func (t *multiWriter) Write(ctx context.Context, p []byte) (n int, err error) {
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for _, w := range t.writers {
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n, err = w.Write(ctx, p)
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if err != nil {
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return
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}
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if n != len(p) {
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err = io.ErrShortWrite
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return
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}
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}
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return len(p), nil
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}
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func newMultiWriter(writers ...writer) writer {
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allWriters := make([]writer, 0, len(writers))
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for _, w := range writers {
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if mw, ok := w.(*multiWriter); ok {
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allWriters = append(allWriters, mw.writers...)
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} else {
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allWriters = append(allWriters, w)
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}
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}
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return &multiWriter{allWriters}
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}
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type writerWrapper struct {
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Writer io.Writer
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}
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func (w *writerWrapper) Write(_ context.Context, p []byte) (n int, err error) {
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return w.Writer.Write(p)
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}
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func newWriter(w io.Writer) writer {
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return &writerWrapper{Writer: w}
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}
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