OpenAI in Rails

intelligence.rb

# frozen_string_literal: true

module Intelligence
  extend ActiveSupport::Concern

  MODEL = 'gpt-4-1106-preview'

  private

  def get_chat_completion(json: true)
    return stub_data if use_stub_data?

    parameters = {
      model: MODEL,
      messages: prompt_messages
    }
    parameters[:response_format] = { type: 'json_object' } if json

    response = openai_client.chat(parameters:)

    JSON.parse(response.dig('choices', 0, 'message', 'content')).deep_symbolize_keys
  end

  def openai_client
    @openai_client ||= OpenAI::Client.new
  end

  def prompt_messages
    [
      { role: 'system', content: system_prompt },
      { role: 'user', content: user_prompt }
    ]
  end

  def user_prompt
    fail NotImplementedError, 'You must implement the user_prompt method'
  end

  def system_prompt
    fail NotImplementedError, 'You must implement the system_prompt method'
  end

  def use_stub_data?
    stub_data.present? && Rails.env.development?
  end

  def stub_data; end
end

prompt.rb

# frozen_string_literal: true

class Prompt
  def self.load(name, **params)
    template = File.read("app/prompts/#{name}.txt.erb")
    erb = ERB.new(template)

    context = OpenStruct.new(params) # rubocop:disable Style/OpenStructUse
    erb.result(context.instance_eval { binding })
  end
end