Saving to DB from Model.rb - ruby-on-rails

Question

When an new order_preview is created, I call USPS for shipping options. If a user updates their zip, I would like the ship_option to reset
Edit: I am no longer calling the intial API call from the view, rather I do an after_create method in the controller.
def get_ship_options
ship_options = {}
#order_preview.fedex_rates.each do |k, v|
if k.service_name == "FedEx Ground Home Delivery" || k.service_name == "FedEx 2 Day" || k.service_name == "FedEx Standard Overnight"
ship_options["#{k.service_name}"] = "#{number_to_currency(k.price.to_f / 100)}"
end
end
#order_preview.usps_rates.each do |k, v|
if k.service_name == "USPS Priority Mail 1-Day"
ship_options["#{k.service_name}"] = "#{number_to_currency(k.price.to_f / 100)}"
end
end
#order_preview.ship_option_hash = ship_options.map { |k,v| ["#{k} - #{v}","#{k} - #{v}" ] }
#order_preview.save
end
I tried using the answers you guys provided, but the before_save didn't actually save the shiphash the way #order_preview.save does at the end of the above method.
I tried using the same idea, but zip_changed? doesn't work in the controller.
How can I save the new hash that is pulled from the model directly over to the #order_preview ?
From the model I now have
Model.rb
def clear_hash
if zip_changed?
get_shipping_rates
end
end
and
ship_options = {}
fedex_rates.each do |k, v|
if k.service_name == "FedEx Ground Home Delivery" || k.service_name == "FedEx 2 Day" || k.service_name == "FedEx Standard Overnight"
ship_options["#{k.service_name}"] = "#{number_to_currency(k.price.to_f / 100)}"
end
end
usps_rates.each do |k, v|
if k.service_name == "USPS Priority Mail 1-Day"
ship_options["#{k.service_name}"] = "#{number_to_currency(k.price.to_f / 100)}"
end
end
ship_option_hash = ship_options.map { |k,v| ["#{k} - #{v}","#{k} - #{v}" ] }
**save ship_option_hash to #order_preview.ship_option_hash**

Answer 1

class OrderPreview
before_save :check_state
def check_state
if zip_changed?
ship_option_hash = nil
end
end
...
end
class OrderPreviewController
def update
#order_preview.update(order_preview_params)
end
...
end

Answer 2

Try changing your callback from after_save to before_save. Record considered changed until the changes are not persisted. Changes are lost when you save your object, that's why your record is unchanged when you check for changes in after_save callback.
It should work this way:
before_save :clear_hash, if: :zip_changed?
def clear_hash
ship_option_hash = nil
end
This way the changes will be saved, because you use before_save. In your code, changes were not saved, because you used after_save callback
You controller:
def update
respond_to do |format|
if #order_preview.update(order_preview_params)
flash[:notice] = "Record was successfully updated"
else
flash[:alert] = "Record was not updated"
end
end
end