Rails：在模型规范中测试文件上传验证（神社 gem）

Question

以下代码在 Rails 4.2 应用程序的模型规范内测试图像验证，其中 RSpec 3.5 和 Shrine gem 用于文件上传。

我的问题是：

您能想出改进以下测试的方法或更好的方法来测试这些验证吗？
如何提高文件大小验证测试的速度？如果可能的话，我想测试它而不必实际上传 >10mb 的文件。

文件上传设置的其他方面在控制器和功能规范中进行了测试，与此问题无关。

RSpec.describe ShareImage, :type => :model do
  describe "#image", :focus do
    let(:image_file) do
      # Could not get fixture_file_upload to work, but that's irrelevant
      Rack::Test::UploadedFile.new(File.join(
        ActionController::TestCase.fixture_path, 'files', filename))
    end
    let(:share_image) { FactoryGirl.build(:share_image, image: image_file) }
    before(:each) { share_image.valid? }

    context "with a valid image file" do
      let(:filename) { 'image-valid.jpg' }
      it "attaches the image to this record" do
        expect(share_image.image.metadata["filename"]).to eq filename
      end
    end

    context "with JPG extension and 'text/plain' media type" do
      let(:filename) { 'image-with-text-media-type.jpg' }
      it "is invalid" do
        expect(share_image.errors[:image].to_s).to include("invalid file type")
      end
    end

    # TODO: Refactor the following test (it takes ~50 seconds to run)
    context "with a >10mb image file" do
      let(:filename) { 'image-11mb.jpg' }
      it "is invalid" do
        expect(share_image.errors[:image].to_s).to include("too large")
      end
    end
  end
end

Answer 1

不是通过 Rack::Test::UploadedFile 路由上传，而是直接使用固定装置或工厂或直接在测试中创建附件元数据记录。最终结果应该是您拥有引用您的文件的附件元数据（上传文件时构建的内容），而无需通过上传代码运行它。我不确定使用 Shrine 执行此操作的具体细节，但该技术适用于 Paperclip 等库。在 Shrine 中，这看起来意味着直接构建一个引用您的文件的 Shrine::UploadedFile 记录。

Answer 2

我建议您分别测试元数据提取和验证。您需要使用真实的元数据提取进行测试 IOs，但对于验证测试，您可以为缓存文件分配所需的元数据，该元数据不一定实际存在。

RSpec.describe ImageUploader do
  def uploaded_file(metadata = {})
    Shrine.uploaded_file(
      "id"       => "123",
      "storage"  => "cache",
      "metadata" => {"mime_type" => "image/jpeg", "size" => 100}.merge(metadata)
    )
  end

  let(:share_image) do
    FactoryGirl.build(:share_image, image: uploaded_file(metadata).to_json)
  end

  let(:metadata) { Hash.new }

  describe "validations" do
    before(:each) { share_image.valid? }

    context "when image is correct" do
      it "passes" do
        expect(share_image.errors).to be_empty
      end
    end

    context "when extension is correct but MIME types isn't" do
      let(:metadata) { Hash["filename" => "image.jpg", mime_type => "text/plain"] }

      it "fails" do
        expect(share_image.errors[:image].to_s).to include("isn't of allowed type")
      end
    end

    context "when file is larger than 10MB" do
      let(:metadata) { Hash["size" => 11 * 1024 * 1024] }

      it "fails" do
        expect(share_image.errors[:image].to_s).to include("too large")
      end
    end
  end
end

Rails：在模型规范中测试文件上传验证（神社 gem）

Rails: Testing file upload validation (Shrine gem) at model spec

ruby

testing

file-upload

ruby-on-rails

shrine