Files
dolt/go/util/progressreader/reader.go
Ben Kalman 270ba908cd Introduce samples/go/blob-get, utility which downloads a noms blob (#2127)
... from a noms database. Right now it's very slow (< 100kb/s).
2016-07-22 17:50:33 -07:00

38 lines
780 B
Go

// Copyright 2016 Attic Labs, Inc. All rights reserved.
// Licensed under the Apache License, version 2.0:
// http://www.apache.org/licenses/LICENSE-2.0
// Package progressreader provides an io.Reader that reports progress to a callback
package progressreader
import (
"io"
"time"
"github.com/attic-labs/noms/go/util/status"
)
type Callback func(seen uint64)
func New(inner io.Reader, cb Callback) io.Reader {
return &reader{inner, uint64(0), time.Time{}, cb}
}
type reader struct {
inner io.Reader
seen uint64
lastTime time.Time
cb Callback
}
func (r *reader) Read(p []byte) (n int, err error) {
n, err = r.inner.Read(p)
r.seen += uint64(n)
if now := time.Now(); now.Sub(r.lastTime) >= status.Rate {
r.cb(r.seen)
r.lastTime = now
}
return
}