ArgumentError (wrong number of arguments (3 for 2)) when used with redis-activesupport

[bencrouse]

I'd like to use this gem, but use Redis as my cache for throttling. I'm using the redis-activesupport gem, and this line: https://github.com/kickstarter/rack-attack/blob/master/lib/rack/attack/cache.rb#L15 seems to be throwing an error because the Redis activesupport class doesn't accept a third arg for options, seen here: https://github.com/jodosha/redis-store/blob/master/redis-activesupport/lib/active_support/cache/redis_store.rb#L93

I'd be willing to work on a fix, but I'm not really sure what to do given there seems to be a lack of standard here.

[ktheory]

Yeah, it's unfortunate that different cache stores have inconsistent arities.

One workaround is to use your own cache store class as a wrapper for the Redis store. See this gist as an example.

I'd welcome a patch to the Rack::Attack::Cache#count method to support redis store. That seems like a good place to iron out the idiosyncrasies between cache stores.

You could check the store.method(:increment).arity, and store.respond_to?(:expire); or check if store.is_a?(ActiveSupport::Cache::RedisStore).

What do you think?