Question

我正在编写一个调用一些外部服务的Sinatra应用程序。我显然希望我的测试能够避免调用真正的服务，所以在我拥有这个时就会这么假设

class MyApp < Sinatra::Base
  get '/my_method' do
    @result = ExternalServiceHandler.new.do_request
    haml :my_view
  end
end

在我的测试中

describe "my app" do
  include Rack::Test::Methods
  def app() MyApp end

  it "should show OK if call to external service returned OK" do
    @external_service_handler = MiniTest::Mock.new
    @external_service_handler.expect :do_request, "OK"

    #Do the injection

    get '/my_method'
    response.html.must_include "OK"
  end

  it "should show KO if call to external service returned KO" do
    @external_service_handler = MiniTest::Mock.new
    @external_service_handler.expect :do_request, "KO"

    #Do the injection

    get '/my_method'
    response.html.must_include "KO"
  end

end

我可以想到两种方法来注入它。我可以调用实例方法或通过构造函数传递依赖项。无论如何，因为机架似乎没有让我访问当前的应用程序实例，我发现这是不可能的。

我可以为此声明一个类方法，但如果可能，我更愿意使用实例。为了保持可能在每种情况下进行不同的注射，并避免在忘记回滚状态时可能损害其他测试的全局状态。

有没有办法实现这个目标？

提前致谢。

Answer 1

似乎有几种选择。您可以通过构造函数传递依赖项，也可以使用设置。

构造函数Args

class MyApp < Sinatra::Base
    def initialize(app = nil, service = ExternalServiceHandler.new)
        super(app)
        @service = service
    end

    get "/my_method" do
        @result = @service.do_request
        haml :my_view
    end
end

在规范中：

describe "my app" do
    include Rack::Test::Methods

    let(:app) { MyApp.new(service) }
    let(:service) { double(ExternalServiceHandler) }

    context "when the external service returns OK" do
        it "shows OK" do
            expect(service).to receive(:do_request).and_return("OK")

            get '/my_method'
            response.html.must_include "OK"
        end
    end

    context "when the external service returns KO" do
        it "shows KO" do
            expect(service).to receive(:do_request).and_return("KO")

            get '/my_method'
            response.html.must_include "KO"
        end
    end
end

设置

class MyApp < Sinatra::Base configure do set :service, ::ExternalServiceHandler.new end get "/my_method" do @result = settings.service.do_request haml :my_view end end

在规范中：

describe "my app" do include Rack::Test::Methods let(:app) { MyApp.new } let(:service) { double(ExternalServiceHandler) } before do MyApp.set :service, service end context "when the external service returns OK" do it "shows OK" do expect(service).to receive(:do_request).and_return("OK") get '/my_method' response.html.must_include "OK" end end context "when the external service returns KO" do it "shows KO" do expect(service).to receive(:do_request).and_return("KO") get '/my_method' response.html.must_include "KO" end end end

Answer 2

我终于设法用

做到了这一点

describe "my app" do

  def app
    @INSTANCE
  end

  before do
    @INSTANCE ||= MyApp.new!
  end

  #tests here

end

虽然我不是特别喜欢使用新的！在它正在工作的那一刻超载。我可以使用app.whatever_method

每次测试时使用的实例

在Sinatra应用程序中注入依赖项

2 个答案: