node-pv

A node.js implementation of the Pipe Viewer utility, useful for inspecting a pipe's traffic.

Example

$ cat /dev/random | pv >/dev/null
18.88MB  00:00:02  [9.59MB/s]^C

Usage

There's an excellent description on Peteris Krumins's blog: A Unix Utility You Should Know About: Pipe Viewer

$ source | pv [OPTIONS] | dest

$ pv [OPTIONS] <FILE> | dest

Options

• -s, --size SIZE: Assume the total amount of data to be transferred is SIZE bytes
• -N, --name NAME: Prefix the output information with NAME

Installation

$ npm install -g node-pv

JS API

var PV = require('node-pv');
var pv = PV({
  size: /* ... */,
  name: /* ... */
});

pv.on('info', function(str){
  process.stderr.write(str);
});

process.stdin.pipe(pv).pipe(process.stdout);

License

MIT