如何在可执行文件中加载Rails.logger？

Question

I have an executable file in my rails app, bin/log_data . In this file, in order to have access to Rails.logger I have to require the following files:

APP_PATH = File.expand_path('../config/application', __dir__)
require 'rails/commands'

This loads the entire rails environment in this one process that runs bin/log_data , and I think the approach is a bit heavy handed. Can anyone share with me how I would just load Rails.logger so that I can do `Rails.logger.info('something relatively important to log')?

Also, just some background info, I want to user Rails.logger because the output goes to log/development.log which is important for what I want to log to be seen in my heroku logs when I tail my app.

Answer 1

You can just create an ActiveSupport::Logger instance:

require 'active_support/logger'
APP_PATH = File.expand_path('../config/application', __dir__)
rails_env = ENV["RAILS_ENV"] || "development"
logger = ActiveSupport::Logger.new(APP_PATH + "/logs/#{rails_env}.log")

If you really want to call it as Rails.logger create a module:

require 'active_support/logger'
require 'active_support/string_inquirer'
APP_PATH = File.expand_path('../config/application', __dir__)
logger = ActiveSupport::Logger.new(APP_PATH + "/logs/#{rails_env}.log")

module Rails
  class << self
    attr_reader :logger
    attr_reader :env
  end
  self.env = ActiveSupport::StringInquirer.new(ENV["RAILS_ENV"] || "development")
  self.logger = ActiveSupport::Logger.new(APP_PATH.join("logs", "#{self.env}.log"))
end

Note that it will not have the exacts same setting as the Rails logger when it comes to log levels and formatting which only really can be obtained by starting the rails app.