github.com/nycdavid/zeus@v0.0.0-20201208104106-9ba439429e03/README.md (about) 1 # Zeus 2 3 [![Join the chat at https://gitter.im/zeus-application-preloader/Lobby](https://badges.gitter.im/zeus-application-preloader/Lobby.svg)](https://gitter.im/zeus-application-preloader/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) 4 [![Build Status](https://travis-ci.org/burke/zeus.svg?branch=master)](https://travis-ci.org/burke/zeus) 5 6 Zeus preloads your Rails app so that your normal development tasks such as `console`, `server`, `generate`, and specs/tests take **less than one second**. 7 8 This screencast gives a quick overview of how to use zeus with Rails. 9 10 [![Watch the screencast!](http://s3.amazonaws.com/burkelibbey/vimeo-zeus.png)](http://vimeo.com/burkelibbey/zeus) 11 12 Zeus is also covered in [RailsCasts episode 412](http://railscasts.com/episodes/412-fast-rails-commands). 13 14 More generally, Zeus is a language-agnostic application checkpointer for non-multithreaded applications. Currently only ruby is targeted, but explicit support for other languages is possible. 15 16 17 ## Requirements (for use with Rails) 18 19 * OS X 10.7+ *OR* Linux 2.6.13+ 20 * Rails 3.x or 4.x 21 * Compatible Ruby installation 22 * Ruby 2.0+ 23 * Rubinius 24 25 **Please note**: Zeus requires your project to be running on a file system that supports FSEvents or inotify. This means no NFS, CIFS, Samba, or VBox/VMWare shared folders. 26 27 28 ## Installation 29 30 Install the gem. 31 32 gem install zeus 33 34 Q: "I should put it in my `Gemfile`, right?" 35 36 A: No. You can, but running `bundle exec zeus` instead of `zeus` adds precious seconds to commands that otherwise would be quite a bit faster. Zeus was built to be run from outside of bundler. 37 38 #### IMPORTANT 39 40 It is common to see tests running twice when starting out with Zeus. If you see your tests/specs running twice, you should try disabling `require 'rspec/autotest'` and `require 'rspec/autorun'` (for RSpec), or `require 'minitest/autorun'` (for Minitest). (see [#134](https://github.com/burke/zeus/issues/134) for more information). 41 42 43 ## Rails Set up 44 45 In your app's directory initialize zeus: 46 47 zeus init 48 49 which will create two files 50 51 custom_plan.rb 52 zeus.json 53 54 Force the test environment: In `test/test_helper.rb` (or `spec/spec_helper.rb` if using RSpec), change: 55 56 57 ENV['RAILS_ENV'] ||= 'test' 58 59 To: 60 61 ENV['RAILS_ENV'] = 'test' 62 63 _More helpful set up hints at [this very nice guide put together by Thoughtbot](https://robots.thoughtbot.com/improving-rails-boot-time-with-zeus)_ 64 65 ## Usage 66 67 Start the server: 68 69 zeus start 70 71 The server will print a list of available commands. 72 73 Run some commands in another shell: 74 75 zeus console 76 zeus server 77 zeus test test/unit/widget_test.rb 78 zeus test spec/widget_spec.rb 79 zeus generate model omg 80 zeus rake -T 81 zeus runner omg.rb 82 83 ## Limitations 84 85 You need to restart zeus if you make changes to various initialization files. Examples of these files include: 86 87 * FactoryGirl factories 88 * RSpec support files 89 90 ## Related gems 91 92 * [Spork](https://github.com/sporkrb/spork) - a [DRb server](http://www.ruby-doc.org/stdlib-1.9.3/libdoc/drb/rdoc/DRb.html) that forks before each run to ensure a clean testing state 93 * [Commands](https://github.com/rails/commands) - a persistent console that runs Rails commands without reloading the env 94 * [Spring](https://github.com/rails/spring) - like Zeus but in pure Ruby, totally automatic, and included in Rails 4.1+. 95 96 If you're switching from Spork, be sure to [read the wiki page on Spork](https://github.com/burke/zeus/wiki/Spork). 97 98 99 ## Customizing Zeus Commands 100 101 To add/modify commands, see [`docs/ruby/modifying.md`](docs/ruby/modifying.md). 102 103 104 ## Contributing 105 106 To get started hacking on Zeus itself, see [`docs/overview.md`](docs/overview.md). 107 108 See also the handy contribution guide at [`contributing.md`](contributing.md). 109 110 111 ## Rails 2.3 Support 112 113 The default plan bundled with zeus only supports Rails 3.x and 4.x. There is a project to provide Rails 2.3 support [here](https://github.com/tyler-smith/zeus-rails23), however it has not been updated in some time. 114 115 ## Legacy Ruby Versions 116 117 Due to official Ruby support lapsing in Feb 2015, Ruby 1.9.3 and below are no longer officially supported. Zeus may work with them but we are not actively supporting them at this time. The last release tested with these versions is [0.15.4](https://github.com/burke/zeus/tree/v0.15.4). 118