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Switching from :transaction to :truncation for some tests doesn't work

Open wjessop opened this issue 5 years ago • 5 comments

So, I have some tests that need truncation because I am testing the whole Sidekiq stack and as a separate process Sidekiq needs to be able to see the records created in the original process. I want to keep the suite in general as :transaction though as the rest of the tests are fine with that strategy.

To do this I add come config to the rspec config:

config.before(:each) do |example|
  DatabaseCleaner.start

  if example.metadata[:truncate]
    DatabaseCleaner.strategy = :truncation
  else
    DatabaseCleaner.strategy = :transaction
  end
end

Then add metadata to the test:

it 'should doit', truncate: true do
  # create records then run the background worker
  # wait for the background worker to finish
end

The problem is that Sidekiq gets ActiveRecord not found errors, and sure enough, there are no rows available to on a separate database (postgres) connection:

connector_test=# select count(*) from contacts;
 count 
-------
     0
(1 row)

If I stick byebug in the test I can confirm that there are in fact records:

(byebug) Contact.count
3

but the strategey does seem to be truncation:

(byebug) DatabaseCleaner[:active_record].strategy.class
DatabaseCleaner::ActiveRecord::Truncation

(byebug) DatabaseCleaner[:active_record].strategy
#<DatabaseCleaner::ActiveRecord::Truncation:0x00007f95e600ff68 @only=nil, @tables_to_exclude=["schema_migrations"], @pre_count=nil, @reset_ids=nil, @cache_tables=true, @db=:default>

If I re-run the test after configuring truncation for all of the tests:

config.before(:suite) do
   DatabaseCleaner.strategy = :truncation
   …
end

I can see that the strategy in the test is the same:

(byebug) DatabaseCleaner[:active_record].strategy
#<DatabaseCleaner::ActiveRecord::Truncation:0x00007f8faf0ccec0 @only=nil, @tables_to_exclude=["schema_migrations"], @pre_count=nil, @reset_ids=nil, @cache_tables=true, @db=:default>

and the records are available in the test:

(byebug) Contact.count
3

but this time the records are also available in the database:

connector_test=# select count(*) from contacts;
 count 
-------
     3
(1 row)

and my test passes. These are the versions of relevant gems I am using

$ bundle info database_cleaner
  * database_cleaner (1.7.0)
	Summary: Strategies for cleaning databases.  Can be used to ensure a clean state for testing.
	Homepage: http://github.com/DatabaseCleaner/database_cleaner
	Path: /Users/will/.rbenv/versions/2.6.5/lib/ruby/gems/2.6.0/gems/database_cleaner-1.7.0

$ bundle info rspec-rails
  * rspec-rails (3.8.3)
	Summary: RSpec for Rails
	Homepage: https://github.com/rspec/rspec-rails
	Path: /Users/will/.rbenv/versions/2.6.5/lib/ruby/gems/2.6.0/gems/rspec-rails-3.8.3

Upgrading database cleaner

So I noticed as I was gathering the version data that database_cleaner was out of date (I could have sworn that I updated it already!). Anyway, after upgrading database_cleaner it now looks like inside the test the reported strategy matches the observed behaviour:

(byebug) DatabaseCleaner[:active_record].strategy
#<DatabaseCleaner::ActiveRecord::Transaction:0x00007ff8ba938928 @db=:default>

This is despite my strategy switch seeming to work OK in the rspec config:

[57, 66] in /Users/will/clients/foo/repos/web-app/spec/rails_helper.rb
   57:   config.before(:each) do |example|
   58:     $redis.flushall
   59:     DatabaseCleaner.start
   60: 
   61:     byebug
=> 62:     if example.metadata[:truncate]
   63:       DatabaseCleaner.strategy = :truncation
   64:     else
   65:       DatabaseCleaner.strategy = :transaction
   66:     end
(byebug) example.metadata[:truncate]
true

and as the test is using transactions not truncation the external process can't see the records and the test fails. Any ideas what's going on here?

wjessop avatar May 22 '20 14:05 wjessop

Hi, @wjessop , thanks for the issue! At a glance, my first guess is that the #clean command is being called before the #strategy= command. Can you confirm or refute this?

botandrose avatar May 22 '20 15:05 botandrose

Fat fingered the Close and comment button instead of the Comment button 😅

botandrose avatar May 22 '20 15:05 botandrose

Thanks for the reply @botandrose! I found some around that looked like it might be the culprit:

config.around(:each) do |example|
  if example.metadata[:bypass_cleaner]
    example.run
  else
    DatabaseCleaner.cleaning do
      example.run
    end
  end
end

I commented it out and the records are now available outside the process, and the test passes, but rather confusingly the strategy still reports as transactional:

(byebug) DatabaseCleaner[:active_record].strategy
#<DatabaseCleaner::ActiveRecord::Transaction:0x00007f8f78b8d300 @db=:default>

I've got Spring disabled BTW, just to eliminate that as a possible issue.

wjessop avatar May 22 '20 15:05 wjessop

Had the same problem and removed the around block, problem solved. Instead of using the around block I use:

  config.before(:each) do
    DatabaseCleaner.start
  end

  config.append_after(:each) do
    DatabaseCleaner.clean
  end

aledalgrande avatar May 25 '20 22:05 aledalgrande