How do I read an incoming webhook post in Rails 4.2

I have something along the lines of this:

case request.request_parameters.keys.first
when "new_subscription_notification"
when "canceled_subscription_notification"
deactivate_subscription params[:expired_subscription_notification]
end

But what I am finding is that the XML webhook request parameters seem to be blank. This is my first time trying to read webhook notifications.. any direction on how to correctly parse an incoming webhook would be awesome!

Hey Aaron,

That all sort of depends on what information is being sent to your webhook. Where is it coming from? What do the params look like? Have any example stuff we can take a look at to get you headed in the right direction?