How do I turn on SQL debug logging for ActiveRecord in RSpec tests?

Question

I have some RSpec tests for my models and I would like to turn on SQL ActiveRecord logging just like I see in the Rails server mode. How to do that?

I start my tests with

RAILS_ENV=test bundle exec rspec my/test_spec.rb

Thanks

score 402 · Answer 1 · answered Apr 01 '11 at 13:50

402

You could try setting the ActiveRecord logger to stdout in your test somewhere. If you're using rspec, maybe in the spec helper?

ActiveRecord::Base.logger = Logger.new(STDOUT)

answered Apr 01 '11 at 13:50

George

4

Much more helpful if you're testing a gem with only `active_record` included as these don't log the SQL by default. – Brendon Muir Jul 12 '18 at 10:26
If you are using IRuby (Jupyter for Ruby), `STDOUT` has been remapped, and you should use `$stdout` instead. – Ulysse BN Aug 08 '19 at 09:19
How do I set this as the default behaviour in rails console? – Marco Prins Sep 07 '22 at 14:41

score 63 · Accepted Answer · edited Jan 07 '16 at 16:28

63

By default, all your db queries will be logged already in test mode. They'll be in log/test.log.

edited Jan 07 '16 at 16:28

philippe_b

answered Mar 09 '11 at 10:40

idlefingers

1

Ah I meant to see it on the console. But this is fair enough. – lzap Mar 09 '11 at 10:50
25

You can watch it in a console using `tail -f log/test.log` – idlefingers Mar 09 '11 at 11:24
I havent realized that this is so easy, so ended up adding a one-lines to dump all instrumentaion from ActiveSupport: `ActiveSupport::Notifications.subscribe do |*args| puts *args end` – Vajk Hermecz Dec 09 '20 at 15:15

score 11 · Answer 3 · answered Sep 01 '15 at 07:20

11

set

config.log_level = :info

in test environment

answered Sep 01 '15 at 07:20

Nicolai

4

or set it to config.log_level = :debug to get maximum output, including each SQL statement executed – Zack Xu Jul 12 '16 at 10:40
What config thing is this? As one might expect, I get "undefined local variable or method 'config' for main:Object". *Edit:* ah this is a Rails thing and not an ActiveRecord thing, nvm... – Luc Apr 10 '21 at 22:01

score 8 · Answer 4 · answered Apr 08 '12 at 23:23

8

if others answers don't work in your case, please check the 'log level' of your test environment.

its default is 'debug', which will output the SQL generated by Rails. if it was set to "info", the SQL will be missing.

answered Apr 08 '12 at 23:23

Siwei

score 2 · Answer 5 · answered Mar 21 '20 at 23:11

2

In your test.rb:

Rails.application.configure do
  ...
  config.logger = ActiveSupport::Logger.new(STDOUT)
end

answered Mar 21 '20 at 23:11

5 Answers5