HGET in private method not returning hash - ruby-on-rails

Question

Some reason my hget is not finding or returning a hash I set in a public method. I can't figure out why.
This is all in one controller that inherits from ApplicationController, which is where I define my redis initializer:
def redis
Thread.current[:redis] ||= Redis.new
end
Then in my controller I do this to set the hash:
def return_customer
email = params["email"]
customer = Customer.find_by(email: email)
credit_amount = customer.credit_amount.to_f
customer_data = {email: email, customer_id: customer.id, credit_amount: credit_amount}
redis.hset("shop:#{customer.shop.id}:customer", customer_data, customer_data.inspect)
render json: customer
end
Then finally I have this private method I use in other methods in the same controller, this is the part that's not working:
private
def get_customer_from_redis
shop = Shop.find_by(shopify_domain: params["shop"])
customer_info = redis.hget("shop:#{shop.id}:customer", customer_data)
eval(customer_info)
end
This is the error that's returned
TypeError (no implicit conversion of nil into String):

Answer 1

I'd recommend you rather than using .inspect use .to_json like this:
def return_customer
email = params["email"]
customer = Customer.find_by(email: email)
credit_amount = customer.credit_amount.to_f
customer_data = {email: email, customer_id: customer.id, credit_amount: credit_amount}
redis.set("shop:#{customer.shop.id}:customer", customer_data.to_json)
render json: customer
end
And then in your private method
def get_customer_from_redis
shop = Shop.find_by(shopify_domain: params["shop"])
customer_info = redis.get("shop:#{shop.id}:customer", customer_data)
JSON.parse(customer_info) if customer_info
end