Output line number in Rails log file

Question

From the Rails Guide on debugging, I found that I can customize output to my log files using this simple method:

logger.debug "Person attributes hash: #{@person.attributes.inspect}"

I decided use this to track how a variable changes and goes through flow control.

I would like to be able to see the line number of my code where logger#debug method was called. Something like this:

logger.debug "Person attributes hash: #{@person.attributes.inspect} from line #{LINE_NUMBER_VAR}"

score 10 · Answer 1 · answered Apr 05 '11 at 09:36

Use a decorator on Logger:

class LoggerDecorator
  def initialize(logger)
    @logger = logger
  end

  %w{debug info warn error fatal}.each do |method|
    eval(<<-eomethod)
      def #{method}(msg)
        @logger.#{method}(position) {msg}
      end
    eomethod
  end

  private
  def position
    caller.at(1).sub(%r{.*/},'').sub(%r{:in\s.*},'')
  end
end

score 8 · Accepted Answer · edited Mar 23 '14 at 16:34

8

logger.debug "Person attributes hash: #{@person.attributes.inspect} from line #{__LINE__}"

edited Mar 23 '14 at 16:34

huntar

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answered Feb 15 '10 at 20:27

DNNX

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See my fisrt sentence. Stackoverflow's message parser don't shows two underscores in a row (hides them or eats up somehow else; maybe makes part of message between underscores bold). – DNNX Feb 15 '10 at 20:33
1

ok great! thanks! I didn't know you meant SO's parsers. so use this: http://dpaste.com/159599/ – user94154 Feb 15 '10 at 20:35

score 4 · Answer 3 · answered Jul 09 '19 at 16:08

4

As of Rails 5, this is now baked in via:

ActiveRecord::Base.verbose_query_logs = true

See the documentation for more

answered Jul 09 '19 at 16:08

Anthony

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Output line number in Rails log file

3 Answers3

Linked