ActiveModel::UnknownAttributeError (unknown attribute 'product_id' for Property.): - ruby-on-rails

Question

So I am struggling with this error. While building a react on rails project.
Completed 500 Internal Server Error in 75ms (ActiveRecord: 6.1ms)
ActiveModel::UnknownAttributeError (unknown attribute 'product_id' for >Property.):
When I run this controller:
class SendDataController < ApplicationController
protect_from_forgery with: :null_session
def save
product = Product.create(name:params[:name], upc:params[:upc].to_i, available_on:params[:availableon])
property = product.Properties.build(name:params[:properties][0][:name])
property.save
end
end
I have tried to things found here and here. But I am getting no where. Below is my current setup.
Models:
class ProductProperty < ApplicationRecord
belongs_to :Property
belongs_to :Product
end
class Product < ApplicationRecord
has_many :Properties
has_many :ProductProperties
end
class Property < ApplicationRecord
belongs_to :Product
has_one :ProductProperty
end
Migration:
class CreateProducts < ActiveRecord::Migration[5.2]
def change
create_table :products do |t|
t.string :name
t.string :upc
t.datetime :available_on
t.timestamps
end
end
end
class CreateProperties < ActiveRecord::Migration[5.2]
def change
create_table :properties do |t|
t.string :name
t.timestamps
end
end
end
class CreateProductProperties < ActiveRecord::Migration[5.2]
def change
create_table :product_properties do |t|
t.string :value
t.timestamps
end
end
end
class AddProductRefToProperties < ActiveRecord::Migration[5.2]
def change
add_reference :properties, :Product, foreign_key: true
end
end
class AddProductRefToProductProperties < ActiveRecord::Migration[5.2]
def change
add_reference :product_properties, :Product, foreign_key: true
end
end
class AddPropertiesRefToProductProperties < ActiveRecord::Migration[5.2]
def change
add_reference :product_properties, :Property, foreign_key: true
end
end
Schema:
ActiveRecord::Schema.define(version: 2018_09_24_163027) do
create_table "product_properties", force: :cascade do |t|
t.string "value"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.integer "Product_id"
t.integer "Property_id"
t.index ["Product_id"], name: "index_product_properties_on_Product_id"
t.index ["Property_id"], name: "index_product_properties_on_Property_id"
end
create_table "products", force: :cascade do |t|
t.string "name"
t.string "upc"
t.datetime "available_on"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "properties", force: :cascade do |t|
t.string "name"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.integer "Product_id"
t.index ["Product_id"], name: "index_properties_on_Product_id"
end
end
Thanks for any help you can give me!

Answer 1

ActiveModel::UnknownAttributeError (unknown attribute 'product_id' for
Property.)
It says there is no product_id in properties table. That is true because you have Product_id instead of product_id, so is the error.
Rails Conventions
By default, attribute names should be snakecase. You should generate a migration which will change Product_id to product_id and migrate as to fix the error. You should also change association names to snakecase as well. For instance
belongs_to :Property
belongs_to :Product
should be
belongs_to :property
belongs_to :product