Shrine: How best to include images with fixtures?

[pmackay]

I'm using shrine (great gem!) and also fixtures for tests and sample seed data. This is a set of handy tips how to use images with CarrierWave, are there any similar docs for including images with some test fixtures when working with Shrine?

[janko]

To achieve a similar setup with Shrine using the filesystem storage, you can upload the file to the storage in setup, and clear the storage in teardown. Then you can assign the uploaded file to the <attachment>_data column in the fixture.

# test/test_helper.rb
class ActiveSupport::TestCase
  setup do
    image = File.open("test/fixtures/files/tapir.jpg")
    Shrine.storages[:store].upload(image, "tapir.jpg")
  end

  teardown do
    Shrine.storages.values.each(&:clear!)
  end
end

# test/fixtures/users.yml
user_with_avatar:
  avatar_data: '{"id":"tapir.jpg","storage":"store","metadata":{"filename":"tapir.jpg","mime_type":"image/jpeg","size":98423}}'

With Shrine you can also use shrine-memory storage, so that you don't have to worry about cleaning the directory (and it's also faster than writing to disk).

# Gemfile
gem "shrine-memory"

# test/test_helper.rb
require "shrine/storage/memory"

Shrine.storages = {
  cache: Shrine::Storage::Memory.new,
  store: Shrine::Storage::Memory.new,
}

class ActiveSupport::TestCase
  setup do
    image = File.open("test/fixtures/files/tapir.jpg")
    Shrine.storages[:store].upload(image, "tapir.jpg")
  end
end

# test/fixtures/users.yml (same as above)
user_with_avatar:
  avatar_data: '{"id":"tapir.jpg","storage":"store","metadata":{"filename":"tapir.jpg","mime_type":"image/jpeg","size":98423}}'

Note that usage questions are best asked on the Shrine google group, GitHub issues should be used here only for bug reports 😉

[janko]

To follow-up here as well, I realized that probably the easiest way to attach files in fixtures is using data URIs, I explained it here.

[pmackay]

Massive thanks for this info @janko-m, much appreciated!

[janko]

@pmackay Unfortunately, this strategy doesn't work, because Rails fixtures seem to require that all key-value pairs are actual columns, it won't accept virtual attributes (like <attachment>_data_uri). See https://github.com/janko-m/shrine/issues/117 for a discussion about this.

With this limitation I didn't see any correct way to setup attachment with Rails fixtures, so I removed the "fixtures" section from the "Testing Shrine" guide.