基于 Rails 中存在的记录创建新记录

Question

I've got a rails app that has two models: address and delivery , where address has_many:deliveries and delivery belongs_to:address .

I'm attempting to create a means by which a single POST request can search to find a matching address in the addresses table using parameters provided in the request, if a match is found create a new delivery . If no address is found, then error the request.

Here's what I have so far (not functional, but hoping I'm close(ish)):

Controller

   class DeliveriesController < ApplicationController
  before_action :confirm_address, only: %i[ create edit update ]
  protect_from_forgery with: :null_session, if: Proc.new {|c| c.request.format.json? }
  

def index
  render json: Delivery.all 
end


def create
  # Delivery.address_id = Address.find_by(numeric: params[:numeric], street_name: params[:street])

  # @address_of_delivery = Delivery.includes(:address).where(numeric: params[:numeric], street_name: params[:street_name], city: params[:city], state: params[:state], zip: params[:zip])

  delivery = Delivery.new(delivery_params)
  # @confirmed_address.id = self.address_id

  puts 'putting'
  # puts @address_of_delivery
  
  if delivery.save
    render json: {status: 'Awesome!', data: delivery}, status: :ok
  else
    render json: {status: 'Boo!', data: delivery.errors}, status: :unprocessable_entity
  end
end 

private

  def delivery_params
    params.permit(:company, :numeric, :street_name, :city, :state, :zip)
  end



  def confirm_address
    @confirmed_address = Address.find_by(numeric: params[:numeric], street_name: params[:street_name], city: params[:city], state: params[:state], zip: params[:zip])
      
      if @confirmed_address.present? 
        puts "found one!"
      else
        puts "NO DICE"
        # self.address_id = confirmed_address.id
  end
  end

As you can see from the controller, I've attempted several paths including using includes and join (not included in snippet), as well as trying to just hard code it.

Also tried to solve through the model, but had trouble accessing the params from the POST request:

class Delivery < ApplicationRecord
    belongs_to :address

    # accepts_nested_attributes_for :address
    attribute :numeric
    attribute :street_name
    attribute :city
    attribute :state 
    attribute :zip

    before_validation :find_associated_address

def find_associated_address
    Address.find_by(numeric: params[:numeric], street_name: params[:street])
    puts 'working in model'
end

end

Copy of the POST request for clarity:

Started POST "/deliveries" for ::1 at 2021-11-20 22:52:00 -0600
Processing by DeliveriesController#create as */*
Parameters: {"company"=>"slowcart", "numeric"=>"123", "street_name"=>"Any Street", "city"=>"NYC", "state"=>"NY", "zip"=>"010101"}

I'm almost certainly making a stupid mistake, but can't find the right means to do what I want to do in the docs/broader web. Rails 6 application, btw.

Answer 1

If you are just looking for a match in addresses table, why not just do:

Address.where(numeric: params[:numeric], street_name: params[:street_name], city: params[:city], state: params[:state], zip: params[:zip])