ruby-on-rails - 每次运行测试时，Rspec 和 Capybara 都会抛出不一致的 Postgresql 错误

Question

Postgresql 抛出各种错误或停止运行我运行使用 Rspec、Capybara-Selenium 和 DatabaseCleaner 的功能测试套件。我无法确定它，因为错误每次都会改变。有时根本没有错误。我将不胜感激任何指导。

这是错误1:

Processing by Api::V1::Company::WagesController#create as JSON
Parameters: {"wage"=>{"user_id"=>33, "amount"=>"100000"}, "user_id"=>"33"}
(39.3ms)  SELECT COUNT(*) FROM "users"
(1.8ms)  BEGIN
NoMethodError: undefined method `nfields' for nil:NilClass:             SELECT tablename
        FROM pg_tables
        WHERE schemaname = ANY (current_schemas(false))

  SQL (12.6ms)  INSERT INTO "wages" ("amount", "created_at", "updated_at", "user_id") VALUES ($1, $2, $3, $4) RETURNING "id"  [["amount", "100000.0"], ["created_at", "2014-06-17 19:47:21.901609"], ["updated_at", "2014-06-17 19:47:21.901609"], ["user_id", 33]]
  (5.1ms)  COMMIT

错误2:

 Started POST "/api/v1/company/users/2/wages" for 127.0.0.1 at 2014-06-17 15:51:32 -0400
 Processing by Api::V1::Company::WagesController#create as JSON
 Parameters: {"wage"=>{"user_id"=>2, "amount"=>"100000"}, "user_id"=>"2"}
 PG::UndefinedTable: ERROR:  relation "id" does not exist
:               SELECT a.attname, format_type(a.atttypid, a.atttypmod),
                pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod
            FROM pg_attribute a LEFT JOIN pg_attrdef d
              ON a.attrelid = d.adrelid AND a.attnum = d.adnum
           WHERE a.attrelid = '"wages"'::regclass
             AND a.attnum > 0 AND NOT a.attisdropped
           ORDER BY a.attnum

错误3:

An error occurred in an after hook
  ActiveRecord::StatementInvalid: PG::NoActiveSqlTransaction: ERROR:  ROLLBACK TO SAVEPOINT can only be used in transaction blocks
: ROLLBACK TO SAVEPOINT active_record_0
  occurred at /Users/codylittlewood/.rvm/gems/ruby-2.1.1@bitcoinpayroll/gems/activerecord-4.1.1/lib/active_record/connection_adapters/postgresql/database_statements.rb:128:in `async_exec'

错误4:(它只是卡在哪里)

(3.2ms)  ALTER TABLE "companies" DISABLE TRIGGER ALL;ALTER TABLE "schema_migrations"     DISABLE TRIGGER ALL;ALTER TABLE "payrolls" DISABLE TRIGGER ALL;ALTER TABLE "payslips" DISABLE    TRIGGER ALL;ALTER TABLE "users" DISABLE TRIGGER ALL;ALTER TABLE "wages" DISABLE TRIGGER ALL
   (18.5ms)  TRUNCATE TABLE "companies", "payrolls", "payslips", "users", "wages" RESTART   IDENTITY CASCADE;
Started POST "/api/v1/company/users/4/wages" for 127.0.0.1 at 2014-06-17 15:57:41 -0400
Processing by Api::V1::Company::WagesController#create as JSON
Parameters: {"wage"=>{"user_id"=>4, "amount"=>"100000"}, "user_id"=>"4"}

在任何这些测试之间都没有更改代码，并且每次都会出现不同的错误。

这是我的spec_helper.rb:

ENV["RAILS_ENV"] ||= 'test'    
require File.expand_path("../../config/environment", __FILE__)
require 'rspec/rails'

RSpec.configure do |config|    
  config.include Devise::TestHelpers, type: :controller

  config.include FactoryGirl::Syntax::Methods

  # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
  config.fixture_path = "#{::Rails.root}/spec/fixtures" 

  # If you're not using ActiveRecord, or you'd prefer not to run each of your
  # examples within a transaction, remove the following line or assign false
  # instead of true.
  config.use_transactional_fixtures = false

  config.before(:suite) do
    DatabaseCleaner.clean_with(:truncation)
  end

  config.before(:each) do
    DatabaseCleaner.strategy = :transaction
  end

  config.before(:each, :js => true) do
    DatabaseCleaner.strategy = :truncation
  end

  config.before(:each) do
    DatabaseCleaner.start
  end

  config.after(:each) do
    DatabaseCleaner.clean
  end

  config.infer_base_class_for_anonymous_controllers = false

  # Run specs in random order to surface order dependencies. If you find an
  # order dependency and want to debug it, you can fix the order by providing
  # the seed, which is printed after each run.
  #     --seed 1234
  config.order = "random"
end

这是我的功能测试spec/features/user_spec.rb:

require 'spec_helper'          
include Warden::Test::Helpers  
Warden.test_mode!              

feature  'Employee management' do
  scenario "adds a new user", :js => true do
    admin = create(:admin)     
    admin.confirmed_at = Time.now   
    admin.save                 
    login_as(admin, :scope => :user)


    visit root_path            

    expect{
      #click_link 'Dashboard'  
      click_link 'Company employees'  
      click_link 'Add an employee'    
      fill_in 'employee[first_name]', with: 'Test'
      fill_in 'employee[last_name]', with: 'User'
      fill_in 'employee[email]', with: '<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="e08e859795938592a08598818d908c85ce838f8d" rel="noreferrer noopener nofollow">[email protected]</a>'
      select "January", from: 'employee[hire_month]'
      select "1", from: 'employee[hire_day]' 
      select "2014", from: 'employee[hire_year]'
      fill_in 'employee[wage]', with: '100000'
      click_button 'Add employee'     
    }.to change(User, :count).by(1) 
    logout :admin
  end
end
Warden.test_reset!

Answer 1

看起来好像有多个线程试图同时访问同一个数据库连接，并且它正在混合查询。这些查询没有理由同时发生。

也许检查一下你的代码，看看是否有什么东西创建了共享连接？看看从字面上注释掉共享连接代码是否有效？