如何使用 rspec 测试 ActionCable 和 Devise？

Question

在我的 Rails (5.1) 应用程序中，我使用 devise 进行身份验证和 ActionCable。

我的 ActionCable 连接看起来像：

module ApplicationCable
  class Connection < ActionCable::Connection::Base
    identified_by :current_user

    def connect
      puts 'current_user:', current_user.inspect

      self.current_user = find_verified_user
      logger.add_tags 'ActionCable', current_user.id
    end

    def disconnect
      # ...
    end

    protected

    def find_verified_user
      verified_user = env['warden'].user
      return verified_user if verified_user

      reject_unauthorized_connection
    end
  end
end

现在我想使用action-cable-testing gem 测试它：

require 'rails_helper'

RSpec.describe ApplicationCable::Connection, type: :channel do
  let(:user) { create(:user) }

  before do
    stub_connection(current_user: user)
  end

  it 'successfully connects' do
    expect { connect '/cable' }.to_not raise_error
  end
end

但得到错误：

ApplicationCable::Connection
current_user:
nil
  successfully connects (FAILED - 1)

Failures:

  1) ApplicationCable::Connection successfully connects
     Failure/Error: expect { connect '/cable' }.to_not raise_error

       expected no Exception, got #<NoMethodError: undefined method `[]' for nil:NilClass> with backtrace:
         # ./app/channels/application_cable/connection.rb:19:in `find_verified_user'
         # ./app/channels/application_cable/connection.rb:8:in `connect'
         # /home/user/.rvm/gems/ruby-2.4.1/gems/action-cable-testing-0.3.1/lib/action_cable/connection/test_case.rb:176:in `connect'
         # ./spec/channels/user_channel_spec.rb:11:in `block (3 levels) in <top (required)>'
         # ./spec/channels/user_channel_spec.rb:11:in `block (2 levels) in <top (required)>'
     # ./spec/channels/user_channel_spec.rb:11:in `block (2 levels) in <top (required)>'

所以我有两个问题：

1. 为什么 current_user是 nil ？
2. 我如何验证用户？

Answer 1

如果要测试与current_user设置的连接，您应该存根env['warden']如下所示https://stackoverflow.com/a/53841098/7121891

如果要测试 Channel 类，请使用已集成到 Rails 6 中的action-cable-testing gem