40 lines
584 B
Go
40 lines
584 B
Go
package slow
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import (
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"context"
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"io"
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"golang.org/x/time/rate"
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)
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type Reader struct {
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ctx context.Context
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limiter *rate.Limiter
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r io.Reader
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}
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var _ io.Reader = Reader{}
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func NewReader(ctx context.Context, bps rate.Limit, r io.Reader) Reader {
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return Reader{
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ctx: ctx,
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limiter: rate.NewLimiter(bps, 8192),
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r: r,
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}
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}
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func (r Reader) Read(b []byte) (int, error) {
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n, err := r.r.Read(b)
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m := 0
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burst := r.limiter.Burst()
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for m < n {
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if err := r.limiter.WaitN(r.ctx, burst); err != nil {
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return n, err
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}
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m += burst
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}
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return n, err
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}
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