JarCastingstream-throttle
A rate limiter for Node.js streams.
API usage
This module exports two classes, Throttle and ThrottleGroup.
Throttle creates a single throttled stream, based on stream.Transform. It accepts an opts parameter with the following keys:
opts.rateis the throttling rate, in bytes per second.opts.chunksize(optional) is the maximum chunk size into which larger writes are decomposed; the default isopts.rate/10.
The opts object may also contain options to be passed to the stream.Transform constructor.
For example, the following code throttles stdin to stdout at 10 bytes per second:
process.stdin.pipe(new Throttle({rate: 10})).pipe(process.stdout)
ThrottleGroup allows the creation of a group of streams whose aggregate bandwidth is throttled. The constructor accepts the same opts argument as for Throttle. Call throttle on a ThrottleGroup object to create a new throttled stream belonging to the group.
For example, the following code creates two HTTP connections to www.google.com:80, and throttles their aggregate (downstream) bandwidth to 10 KB/s:
var addr = { host: 'www.google.com', port: 80 };
var tg = new ThrottleGroup({rate: 10240});
var conn1 = net.createConnection(addr),
conn2 = net.createConnection(addr);
var thr1 = conn1.pipe(tg.throttle()),
thr2 = conn2.pipe(tg.throttle());
// Reads from thr1 and thr2 are throttled to 10 KB/s in aggregate
Command line usage
This package installs a throttleproxy binary which implements a command-line utility for throttling connections. Run throttleproxy -h for instructions.
Contributing
Feel free to open an issue or send a pull request.
License
BSD-style. See the LICENSE file.
Author
Copyright © 2013 Tiago Quelhas. Contact me at <[email protected]>.