利用io.Reader/Writers實現進度條的Go(golang)包：ioprogress

ioprogress是一個Go (golang)庫利用 io.Reader 和 io.Writer 來繪制進度條。它主要用在CLI 應用中。

用法

Here is an example of outputting a basic progress bar to the CLI as we're "downloading" from some other io.Reader (perhaps from a network connection):

// Imagine this came from some external source, such as a network connection,
// and that we have the full size of it, such as from a Content-Length HTTP
// header.
var r io.Reader

// Create the progress reader
progressR := &ioprogress.Reader{
    Reader: r,
    Size:   rSize,
}

// Copy all of the reader to some local file f. As it copies, the
// progressR will write progress to the terminal on os.Stdout. This is
// customizable.
io.Copy(f, progressR)

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