Throttlex

Throttlex is an efficient Elixir rate limiter based on erlang ETS.

Instalation

1. Add Throttlex to your mix.exs dependencies:

   def deps do
     [{:throttlex, "~> 0.0.9"}]
   end

2. List :throttlex in your application dependencies:

   def application do
     [applications: [:throttlex]]
   end

3. Put configuration in your config file:

   config :throttlex, :buckets,
     user_rate_web: [rate_per_second: 10, max_accumulated: 4, cost: 1],
     user_rate_ios: [rate_per_second: 10, max_accumulated: 4, cost: 1]

Usage

Check rate:

The Throttlex.check function will return :ok if the user's request could be allowed, otherwise will return :error. For one bucket, same rate_per_second, max_accumulated should be passed to &check/5.

• bucket: an atom representing bucket name (also an ETS table).
• id: id.
• cost(optional): costs of each request.

iex> Throttlex.check(:user_rate_web, 1)
:ok
iex> Throttlex.check(:user_rate_web, 1)
:ok
iex> Throttlex.check(:user_rate_web, 1)
:error

For user id 1, one extra request will be added to bucket, maximum accumulated requests number is 4, and every request will cost 1 token. First request will be permitted. Second request is permitted also since we allowed 2 requests maximum. If the third request is made within 1 second (the recovery time), it will return :error.

iex> Throttlex.clear(:user_rate_web)
:ok

iex> Throttlex.clear([:user_rate_web, user_rate_ios])
:ok

Clear given table/tables, will always return :ok.

Testing

mix test