# AshRateLimiter An extension for `Ash.Resource` which adds the ability to rate limit access to actions. ## rate_limit Configure rate limiting for actions. #### Backend This library uses a pluggable backend for rate limiting. Any module implementing the `AshRateLimiter.Backend` behaviour can be used. See `AshRateLimiter.Backend` for more information. #### Keys The backend uses a "key" to identify which bucket to allocate an event against. You can use this to tune the rate limit for specific users or events. You can provide either a statically configured string key, or a function of arity one or two, which when given a query/changeset and optional context object can generate a key. The default is `AshRateLimiter.key_for_action/2`. See it's docs for more information. ### Nested DSLs * [action](#rate_limit-action) ### Examples ``` rate_limit do backend MyApp.RateLimiter action :create, limit: 10, per: :timer.minutes(5) end ``` ### Options | Name | Type | Default | Docs | |------|------|---------|------| | [`backend`](#rate_limit-backend){: #rate_limit-backend .spark-required} | `module` | | The rate limiting backend module | ### rate_limit.action ```elixir action action ``` Configure rate limiting for a single action. It does this by adding a global change or preparation to the resource with the provided configuration. For more advanced configuration you can add the change/preparation directly to your action using `AshRateLimiter.BuiltinChanges.rate_limit/1` or `AshRateLimiter.BuiltinPreparations.rate_limit/1`. ### Arguments | Name | Type | Default | Docs | |------|------|---------|------| | [`action`](#rate_limit-action-action){: #rate_limit-action-action .spark-required} | `atom` | | The name of the action to limit | ### Options | Name | Type | Default | Docs | |------|------|---------|------| | [`limit`](#rate_limit-action-limit){: #rate_limit-action-limit .spark-required} | `pos_integer` | | The maximum number of events allowed within the given period | | [`per`](#rate_limit-action-per){: #rate_limit-action-per .spark-required} | `pos_integer` | | The time period (in milliseconds) for in which events are counted | | [`key`](#rate_limit-action-key){: #rate_limit-action-key } | `String.t \| (any -> any) \| (any, any -> any)` | `&AshRateLimiter.key_for_action/2` | The key used to identify the event. See above. | | [`description`](#rate_limit-action-description){: #rate_limit-action-description } | `String.t` | | A description of the rate limit | | [`on`](#rate_limit-action-on){: #rate_limit-action-on } | `:before_action \| :before_transaction` | `:before_action` | The lifecycle hook to use for rate limiting. `:before_action` (default) runs inside the transaction; `:before_transaction` runs outside the transaction, after validations. | ### Introspection Target: `AshRateLimiter`