Raisl 4.2 + Capybara + Paperclip = Race condition

rubyonrails-talk
#1

Hi!

I’m upgrading a small Rails 4.1.x app to 4.2.

All my test suite is passing, except one spec:

scenario “showing a video called from a track” do

visit video_path(video, level_id: level.id)

sign_in create(:confirmed_user)

expect(page).to have_selector “video[poster=”#{video.poster(:original)}"]"

end

``

Here is the factory:

FactoryGirl.define do

factory :video do

title “Cadastrando um cliente”

poster { Rack::Test::UploadedFile.new("#{::Rails.root}/spec/fixtures/image.png", “image/png”) }

video { Rack::Test::UploadedFile.new("#{::Rails.root}/spec/fixtures/video.mp4", “video/mp4”) }

end

end

``

That’s the problem:

Video Pages

when showing

showing a video called from a track (FAILED - 1)

HTML screenshot: /Users/cezinha/dev/universidade/tmp/capybara/2015-01-06-09-31-30-screenshot-showing-a-video-called-from-a-track.html

Failures:

  1. Video Pages when showing showing a video called from a track

    Failure/Error: expect(page).to have_selector “video[poster=”#{video.poster(:original)}"]"

    expected to find css "video[poster=\"/system/videos/posters/000/000/001/original/image.png?1420543889\"]" but there were no matches

    ./spec/features/video_spec.rb:66:in `block (3 levels) in <top (required)>’

``

When I inspect the generated HTML I have:

<video class=“img-responsive”

controls preload autoplay poster="/system/videos/posters/000/000/001/original/image.png?1420543954"

data-level_id=1

``

When I inspect the video.poster(:original) I have:

/system/videos/posters/000/000/001/original/image.png?1420543953

``

The worst: sometimes it pass and sometimes not.

My impression is that the content of the file is changing while I’m testing and because of this, the fingerprint is different too.

Does anyone can help me?

Thanks.

#2

That’s not a fingerprint, it’s a timestamp. Who is inserting that timestamp?

Fred

#3

It’s generated by Paperclip!

image001.jpg

#4

Hi Fred!

I beg your pardon, but I think you’re not right.

The ?“nnnnnnn” is really a fingerprint generated by paperclip. I checked here:

https://github.com/thoughtbot/paperclip#md5-checksum--fingerprint

Do you have any idea to solve my problem?

I only think in two options:

  1. The assertion is happening while the factory girl is loading the sample file.

  2. For a weird reason, factory girl could be loading the sample file twice.

I’m two days working on it and I’m not finding a solution.

Thanks.

#5

Hi Fred!

I beg your pardon, but I think you're not right.

The ?"nnnnnnn" is really a fingerprint generated by paperclip. I checked here:

https://github.com/thoughtbot/paperclip#md5-checksum--fingerprint

It's definitely not an md5 fingerprint - it's too short. Furthermore, when interpreted as a timestamp (try using Time.at) it returns a time a few minutes before your original post.

https://github.com/thoughtbot/paperclip/blob/master/lib/paperclip/url_generator.rb Seems to indicate that it uses the updated_at of the model. Perhaps a change in rails 4.2 is causing your model to be saved a second time during the call to visit. If that second save happens within the same second your spec will pass if not it will fail.

You could also take the view that the value of the timestamp isn't important and change your spec to only look at the path.

Fred

#6

Hi Fred!

I wouldn’t like to change my test, but I had to!

Thanks for your attention!