Testing image attachments or uploads in Rails

testing_image_attachments_in_rails.md

Testing Image Attachments/Uploads in Rails

Model

We need to use File.open(Rails.root.join("<image_path>")).

File.open(Rails.root.join("test/fixtures/files/sample.jpeg"))

Example:

# group_test.rb

test "is valid" do
  assert fake_group.valid?
end

def fake_group(params = {})
  @fake_group ||= Group.new(
    owner:       params[:owner]       || users(:phil),
    name:        params[:name]        || "Test group",
    description: params[:description] || "Test group description.",
    image:       params[:image]       || valid_image
  )
end

def valid_image
  File.open(Rails.root.join("test/fixtures/files/sample.jpeg"))
end

Controller

We need to use fixture_file_upload("<image_path>", "image/<extension>".

fixture_file_upload("test/fixtures/files/sample.jpeg", "image/jpeg")

Example:

# groups_controller_test.rb

test "should create group" do
  user = users(:phil)

  log_in_as(user)

  assert_difference("Group.count") do
    post groups_url, params: { group: {
      name:        "Test group",
      description: "Test group description.",
      image:       upload_valid_image
    } }
  end

  assert_redirected_to group_url(Group.last)
end

def upload_valid_image
  fixture_file_upload("test/fixtures/files/sample.jpeg", "image/jpeg")
end

Integration

We need to use attach_file("<image_id>", "<image_path>").

attach_file "group_image", "test/fixtures/files/sample.jpeg"

Example:

# groups_creation_test.rb

test "user creates a group" do
  user = users(:phil)

  log_in_as(user)
  visit root_path

  within ".navbar" do
    click_on user.name
  end

  within ".dropdown-menu" do
    click_on "Create group"
  end

  fill_in "Name",        with: "Test group"
  fill_in "Description", with: "Test group description."

  attach_valid_image

  within "form" do
    click_on "Create group"
  end

  assert page.has_content? "Yay! You created a group!"
end

def attach_valid_image
  attach_file "group_image", "test/fixtures/files/sample.jpeg"
end