NAME

    Redis::RateLimit - Sliding window rate limiting with Redis

VERSION

    version 1.0000

SYNOPSIS

        use Redis;
        use Redis::RateLimit;
    
        my $rules = [
            { interval => 1, limit => 5 },
            { interval => 3600, limit => 1000, precision => 100 },
        ];
    
        my $redis_client = Redis->new;
        my $limiter = Redis::RateLimit->new(
            redis => $redis_client,
            rules => $rules,
        );
    
        for ( 1..10 ) {
            say 'Is rate limited? ', $limiter->incr('127.0.0.1') ? 'true' : 'false';
        };

    Output:

        Is rate limited? false
        Is rate limited? false
        Is rate limited? false
        Is rate limited? false
        Is rate limited? false
        Is rate limited? true
        Is rate limited? true
        Is rate limited? true
        Is rate limited? true
        Is rate limited? true

DESCRIPTION

    A Perl library for efficient rate limiting using sliding windows stored
    in Redis.

    This is a port of RateLimit.js <http://ratelimit.io/> without the
    non-blocking goodness.

 Features

      * Uses a sliding window for a rate limit rule

      * Multiple rules per instance

      * Multiple instances of RateLimit side-by-side for different
      categories of users.

      * Whitelisting/blacklisting of keys

 Background

    See this excellent articles on how the sliding window rate limiting
    with Redis works:

      * Introduction to Rate Limiting with Redis Part 1
      <http://www.dr-josiah.com/2014/11/introduction-to-rate-limiting-with.html>

      * Introduction to Rate Limiting with Redis Part 2
      <http://www.dr-josiah.com/2014/11/introduction-to-rate-limiting-with_26.html>

    For more information on the `weight` and `precision` options, see the
    second blog post above.

 TODO

      * Port the middleware for Plack

ATTRIBUTES

 redis

    Redis client. If none is provided, a default is constructed for
    127.0.0.1:6379.

 prefix

    A prefix to be included on each redis key. This prevents collisions
    with multiple applications using the same Redis DB. Defaults to
    'ratelimit'.

 client_prefix

    Set this to a true value if using a Redis client that supports
    transparent prefixing. Defaults to 0.

 rules

    An arrayref of rules, each of which is a hashref with interval, limit,
    and optionally precision values.

METHODS

 check($key | \@keys)

    Returns true if any of the keys are rate limited.

 incr($key | \@keys [, $weight ])

    Returns true if any of the keys are rate limited, otherwise, it
    increments counts and returns false.

 keys

    Returns all of the rate limiter's with prefixes removed.

 violated_rules($key | \@keys)

    Returns a list of rate limit rules violated for any of the keys, or an
    empty list.

 limited_keys($key | \@keys)

    Returns a list of limited keys.

 whitelist($key | \@keys)

    Adds the keys to the whitelist so they are never rate limited.

 unwhitelist($key | \@keys)

    Removes the keys from the whitelist.

 blacklist($key | \@keys)

    Adds the keys to the blacklist so they are always rate limited.

 unblacklist($key | \@keys)

    Removes the keys from the blacklist.

AUTHOR

    Marc Mims <marc@questright.com>

COPYRIGHT AND LICENSE

    This software is Copyright (c) 2016 by Marc Mims.

    This is free software, licensed under:

      The MIT (X11) License