building a ruby conditional to check for nested params

Question

I'm curious in an controller action, how I can do some simple validation of nested params?

def create
# validate incoming post request
errors = Array.new
person = params[:person]
event  = params[:event]

errors << "person email should not be empty" if person[:email].blank?
errors << "person name should not be empty"  if person[:name].blank?
errors << "event name should not be empty"   if event[:name].blank?

This type of check is barfing. I'm trying to scan for some nested json params, so for example making a post request on

    "person":
            {
                    "email":"foo@gmail.com",
                    "name":"foo"
            },

This will validate fine because the nested name is there. Although if I do a request without the nested value, it will barf. How could I write a conditional to check for the nested value, and only stuff in the error value if it's empty. Otherwise, if there is no nested value just continue as normal.

Answer 1

You could use the has_key? method available on Hash class.

errors << "person email should not be empty" if person.has_key?(:email) && person[:email].blank?