An Erlang application to limit rate of requests. Initially developed to limit requests to Mochiweb server.
Just udate your rebar.config file with
{deps, [
{raterlimiter, ".*",
{git, "git://github.com/Gromina/raterlimiter.git", "master"}}
]}.
Raterlimiter needs 2 application parameters -
timeout - Timeout to delete unused bucket (milliseconds)
cleanup_rate - How often to run clenup funciton (milliseconds)
If you need to change them, update your app.config with
{raterlimiter, [
{timeout, 300000}, % bucket maximum lifetime (5 min)
{cleanup_rate, 10000} % cleanup every X milliseconds (every 10 secs)
]}
Once you start the application with
application:start(raterlimiter).
or with command line
erl -s raterlimiter
you can start rate limiting any of your tasks.
raterlimiter:check_rate(RequestID, BucketTimeFrame, RequestsLimit)
which returns either {ok, continue} or {fail, Limit}
RequestId - Your task, request or client ID. In case of Mochiweb it is probably mochiweb_request:get(peer)
BucketTimeFrame - Time frame to apply limit, in milliseconds. 1000 means change bucket every second
RequestsLimit - Maximum number of requests allowed to do within one bucket
Alexander Sorokin gromina@gmail.com, http://alexsorokin.ru