Allow using middleware with custom configuration

[franzliedke]

So far, the documentation is suggesting 100% global configuration for what's essentially a middleware. I do wonder whether there are any reasons not to support passing in a configuration directly wherever I am adding a middleware to my stack. (This could be a base controller with per-controller middleware.)

Pseudo-code example:

config = Rack::Attack::Configuration.new.tap do
  _1.throttle("my_api.throttle_per_minute", limit: 20,  period: 1.minute, &:ip)
  _1.throttle("my_api.throttle_per_hour",   limit: 100, period: 1.hour,   &:ip)
end

use Rack::Attack, config

Primarily, this would let me avoid mixing filters (for request type and path) with the discriminator block - I'd rather keep the filtering to my middleware builder.

Let me know what you think about this idea, and especially what may speak against this. Then I'm happy to send a "real" pull request with tests etc.

[santib]

Hi @franzliedke I think this one would be solved by #442 , right?

[franzliedke]

@santib Yes, totally! Looks like I only got through the first half of the PR list. 😇