An asynchronous token-based throttle. E.g. rate-limit API access by token/IP.
Asynchronously rate-limit by a key. E.g. set thresholds for access to your API by username/token, or IP address.
The default storage is in process memory, but it is easily pluggable by providing a thin wrapper to whatever storage system you would like to use, e.g. Redis for cross-process or cross-machine rate-limiting.
// Create a throttle with 100 access limit per second.var throttle = require"tokenthrottle"rate: 100;// in some_function that you want to rate limitthrottlerateLimitid/* ... handle err ... */if limitedreturn resnext"Rate limit exceeded, please slow down.";else/* ... do work ... */
Convenient wrappers for this library with different storage back-ends:
There are a number of options available to control how the throttle mechanism works.
burstact. [default: 1000]
put(key, object, cb)and
var throttle = require"tokenthrottle"rate: 100 // replenish actions at 100 per minuteburst: 200 // allow a maximum burst of 200 actions per minutewindow: 60000 // set the throttle window to a minuteoverrides:"127.0.0.1": rate: 0 // No limit for localhost"Joe Smith": rate: 10 // token "Joe Smith" gets 10 actions per second (Note defaults apply here, does not inherit)"2da0f39": rate: 1000 burst: 2000 window: 1000 // Allow a lot more actions to this token.;
Here's an example of a custom token table that would use Redis:
(But don't do it manually, use tokenthrottle-redis)
thisclient = redisClient;thisclienthgetallkey cb;thisclienthmsetkey value cb;// Note: you may want to consider expiring these keys to prevent Redis memory bloat.var throttle = require"tokenthrottle"rate: 100tokensTable: require"redis"createClient
This library is code derived from the original built-in throttle for restify and contains many portions originally written by Mark Cavage. It is actually designed with Restify backward-compatibility in mind for Synchronous in-memory only token-table implementations by wrapping synchronous put/get calls with async versions.
(The MIT License)
Copyright (c) Bryce B. Baril email@example.com
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