ERPLookup

class ERP
  def self.flat_bom(part_number)
    Rails.cache.fetch("erp_flat_bom_#{part_number}") do
      parts = {}
      
      bom = ERP.get_bom(part_number)
      bom.items.each do |item|
         [... recursively go down to get every part in this indented BOM...]
      end
      parts
    end
  end
  
  def self.get_bom(part_number)
    [ ... some fancy caching here ...]
  end
end

gistfile1.txt

class CreateRouter < ActiveRecord::Migration
  def change
    create_table :router_component_groups do |t|
      t.string  :description
      t.integer :position
      t.string  :preface_text
      t.string  :postface_text
      t.string  :verb
      t.boolean :ignore
      t.boolean :immutable
      t.boolean :show_image
      t.references :step
      t.timestamps null: false
    end

    create_table :router_components do |t|
      t.string     :part_number
      t.string     :description
      t.integer    :position
      t.references :component_group
      t.timestamps null: false
    end
  end
end

SoftwareSpecification.rb

class CreateSoftwareSpecifications < ActiveRecord::Migration
  def change
    create_table :software_specifications do |t|
      t.string :software_part_number
      
      ...
      t.string :parameter (x20)
      ...
      
      t.timestamps
    end
    add_index :software_specifications, [:software_part_number], unique: true
  end
end

unit_information.rb

class UnitInformation
  attr_reader :parts_list, :part_number
  def initialize(part_number, parts_list)
    @part_number = part_number
    @parts_list  = parts_list
  end

  def determine_software_pn
    parts_list.keys.find do |pn|
      ... regexes here ...
    end
  end

  def software_part_number
    @_software_part_number ||= determine_software_pn
    return @_software_part_number
  end

  def load_software_specifications
    @_software_specifications = SoftwareSpecifications.where(part_number: software_part_number) # Load from DB...
  end

  def test_parameters
    @_software_specifications ||= load_software_specifications
  end

  def test_parameter_a
    return software_specification.test_parameter_a
  end

  def determine_motor_part_numbers
    part_numbers = []
    ComponentGroup.where(description: "Motors").each do |group|
       group.components.each do |pn, qty|
         part_numbers << pn if parts_list.has_key?(pn)
       end  
    end
    return part_numbers
  end
  
  def motor_part_numbers
     @_motor_part_numbers ||= determine_motor_part_number
    return @_motor_part_numbers
  end
end