Q:

NodeJS: any module to limit express request rate

one of my friend is looking for nodejs module:

can limit express request rate.
to prevent robots.

had google, but only found connect has a limit middleware but only limit file size.

A:

Update:
I did multiple searches(also searched npmjs.org):

http://www.google.com/search?q=rate+limit+http+firewall&hl=en
http://www.google.com/search?q=rate+limit+http+iptables&hl=en
http://www.google.com/search?q=connect+node.js+limit+request+rate&hl=en -> http://journal.paul.querna.org/articles/2010/09/04/limiting-concurrency-node-js/ 
https://npmjs.org/browse/keyword/rate -> https://npmjs.org/package/rate-limiter && https://npmjs.org/package/express-rate

Just did some Google searching with hopefully a solution:

http://www.debian-administration.org/articles/187
http://journal.paul.querna.org/articles/2010/09/04/limiting-concurrency-node-js/
https://github.com/jhurliman/node-rate-limiter
https://npmjs.org/package/express-rate
https://github.com/cloudkick/rate-limiter
https://npmjs.org/package/express-rate
https://npmjs.org/package/limiter

