如何在Capybara和RSpec中测试CSV文件下载？

Question

控制器中包含以下内容：

respond_to do |format|
  format.csv  { send_data as_csv, type:'text/csv' }
end

规格：

click_link 'Download CSV'
page.driver.browser.switch_to.alert.accept

expect( page ).to have_content csv_data

但这不起作用：

Failure/Error: page.driver.browser.switch_to.alert.accept
Selenium::WebDriver::Error::NoAlertPresentError: No alert is present

我看到“保存文件”对话框，但显然不是“警告”对话框。

如何单击确定并让水豚看到数据？

Answer 1

改编自CollectiveIdea和其他来源。

在OSX上工作。Firefox 34.0.5

规格：

  describe 'Download CSV' do
    let( :submission_email ){ '[e-mail]' }
    let( :email_csv ){ "id,email,created_at\n1,#{ submission_email }," }

    specify do
      visit '/emails'
      expect( page ).to have_content 'Email Submissions'

      click_on 'Download CSV'

      expect( DownloadHelpers::download_content ).to include email_csv
    end
  end

规范助手：

require 'shared/download_helper'

Capybara.register_driver :selenium do |app|
  profile = Selenium::WebDriver::Firefox::Profile.new
  profile['browser.download.dir'] = DownloadHelpers::PATH.to_s
  profile['browser.download.folderList'] = 2

  # Suppress "open with" dialog
  profile['browser.helperApps.neverAsk.saveToDisk'] = 'text/csv'
  Capybara::Selenium::Driver.new(app, :browser => :firefox, :profile => profile)
end

config.before( :each ) do
    DownloadHelpers::clear_downloads
end

共享/download_helper.rb：

module DownloadHelpers
  TIMEOUT = 1
  PATH    = Rails.root.join("tmp/downloads")

  extend self

  def downloads
    Dir[PATH.join("*")]
  end

  def download
    downloads.first
  end

  def download_content
    wait_for_download
    File.read(download)
  end

  def wait_for_download
    Timeout.timeout(TIMEOUT) do
      sleep 0.1 until downloaded?
    end
  end

  def downloaded?
    !downloading? && downloads.any?
  end

  def downloading?
    downloads.grep(/\.part$/).any?
  end

  def clear_downloads
    FileUtils.rm_f(downloads)
  end
end