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Diffstat (limited to 'guides/source/plugins.md')
| -rw-r--r-- | guides/source/plugins.md | 123 |
1 files changed, 66 insertions, 57 deletions
diff --git a/guides/source/plugins.md b/guides/source/plugins.md index f8f04c3c67..7b7eb80081 100644 --- a/guides/source/plugins.md +++ b/guides/source/plugins.md @@ -3,9 +3,9 @@ The Basics of Creating Rails Plugins A Rails plugin is either an extension or a modification of the core framework. Plugins provide: -* a way for developers to share bleeding-edge ideas without hurting the stable code base -* a segmented architecture so that units of code can be fixed or updated on their own release schedule -* an outlet for the core developers so that they don’t have to include every cool new feature under the sun +* A way for developers to share bleeding-edge ideas without hurting the stable code base. +* A segmented architecture so that units of code can be fixed or updated on their own release schedule. +* An outlet for the core developers so that they don't have to include every cool new feature under the sun. After reading this guide, you will know: @@ -15,7 +15,7 @@ After reading this guide, you will know: This guide describes how to build a test-driven plugin that will: * Extend core Ruby classes like Hash and String. -* Add methods to ActiveRecord::Base in the tradition of the 'acts_as' plugins. +* Add methods to `ActiveRecord::Base` in the tradition of the `acts_as` plugins. * Give you information about where to put generators in your plugin. For the purpose of this guide pretend for a moment that you are an avid bird watcher. @@ -34,15 +34,21 @@ different rails applications using RubyGems and Bundler if desired. Rails ships with a `rails plugin new` command which creates a - skeleton for developing any kind of Rails extension with the ability - to run integration tests using a dummy Rails application. See usage - and options by asking for help: +skeleton for developing any kind of Rails extension with the ability +to run integration tests using a dummy Rails application. Create your +plugin with the command: ```bash -$ rails plugin --help +$ rails plugin new yaffle ``` -Testing your newly generated plugin +See usage and options by asking for help: + +```bash +$ rails plugin new --help +``` + +Testing Your Newly Generated Plugin ----------------------------------- You can navigate to the directory that contains the plugin, run the `bundle install` command @@ -51,7 +57,7 @@ You can navigate to the directory that contains the plugin, run the `bundle inst You should see: ```bash - 2 tests, 2 assertions, 0 failures, 0 errors, 0 skips + 1 runs, 1 assertions, 0 failures, 0 errors, 0 skips ``` This will tell you that everything got generated properly and you are ready to start adding functionality. @@ -68,7 +74,7 @@ In this example you will add a method to String named `to_squawk`. To begin, cre require 'test_helper' -class CoreExtTest < Test::Unit::TestCase +class CoreExtTest < ActiveSupport::TestCase def test_to_squawk_prepends_the_word_squawk assert_equal "squawk! Hello World", "Hello World".to_squawk end @@ -79,19 +85,19 @@ Run `rake` to run the test. This test should fail because we haven't implemented ```bash 1) Error: - test_to_squawk_prepends_the_word_squawk(CoreExtTest): - NoMethodError: undefined method `to_squawk' for [Hello World](String) - test/core_ext_test.rb:5:in `test_to_squawk_prepends_the_word_squawk' + CoreExtTest#test_to_squawk_prepends_the_word_squawk: + NoMethodError: undefined method `to_squawk' for "Hello World":String + /path/to/yaffle/test/core_ext_test.rb:5:in `test_to_squawk_prepends_the_word_squawk' ``` Great - now you are ready to start development. -Then in `lib/yaffle.rb` require `lib/core_ext`: +In `lib/yaffle.rb`, add `require 'yaffle/core_ext'`: ```ruby # yaffle/lib/yaffle.rb -require "yaffle/core_ext" +require 'yaffle/core_ext' module Yaffle end @@ -112,13 +118,13 @@ end To test that your method does what it says it does, run the unit tests with `rake` from your plugin directory. ```bash - 3 tests, 3 assertions, 0 failures, 0 errors, 0 skips + 2 runs, 2 assertions, 0 failures, 0 errors, 0 skips ``` To see this in action, change to the test/dummy directory, fire up a console and start squawking: ```bash -$ rails console +$ bin/rails console >> "Hello World".to_squawk => "squawk! Hello World" ``` @@ -126,8 +132,8 @@ $ rails console Add an "acts_as" Method to Active Record ---------------------------------------- -A common pattern in plugins is to add a method called 'acts_as_something' to models. In this case, you -want to write a method called 'acts_as_yaffle' that adds a 'squawk' method to your Active Record models. +A common pattern in plugins is to add a method called `acts_as_something` to models. In this case, you +want to write a method called `acts_as_yaffle` that adds a `squawk` method to your Active Record models. To begin, set up your files so that you have: @@ -136,14 +142,14 @@ To begin, set up your files so that you have: require 'test_helper' -class ActsAsYaffleTest < Test::Unit::TestCase +class ActsAsYaffleTest < ActiveSupport::TestCase end ``` ```ruby # yaffle/lib/yaffle.rb -require "yaffle/core_ext" +require 'yaffle/core_ext' require 'yaffle/acts_as_yaffle' module Yaffle @@ -162,9 +168,9 @@ end ### Add a Class Method -This plugin will expect that you've added a method to your model named 'last_squawk'. However, the -plugin users might have already defined a method on their model named 'last_squawk' that they use -for something else. This plugin will allow the name to be changed by adding a class method called 'yaffle_text_field'. +This plugin will expect that you've added a method to your model named `last_squawk`. However, the +plugin users might have already defined a method on their model named `last_squawk` that they use +for something else. This plugin will allow the name to be changed by adding a class method called `yaffle_text_field`. To start out, write a failing test that shows the behavior you'd like: @@ -173,7 +179,7 @@ To start out, write a failing test that shows the behavior you'd like: require 'test_helper' -class ActsAsYaffleTest < Test::Unit::TestCase +class ActsAsYaffleTest < ActiveSupport::TestCase def test_a_hickwalls_yaffle_text_field_should_be_last_squawk assert_equal "last_squawk", Hickwall.yaffle_text_field @@ -190,16 +196,16 @@ When you run `rake`, you should see the following: ``` 1) Error: - test_a_hickwalls_yaffle_text_field_should_be_last_squawk(ActsAsYaffleTest): + ActsAsYaffleTest#test_a_hickwalls_yaffle_text_field_should_be_last_squawk: NameError: uninitialized constant ActsAsYaffleTest::Hickwall - test/acts_as_yaffle_test.rb:6:in `test_a_hickwalls_yaffle_text_field_should_be_last_squawk' + /path/to/yaffle/test/acts_as_yaffle_test.rb:6:in `test_a_hickwalls_yaffle_text_field_should_be_last_squawk' 2) Error: - test_a_wickwalls_yaffle_text_field_should_be_last_tweet(ActsAsYaffleTest): + ActsAsYaffleTest#test_a_wickwalls_yaffle_text_field_should_be_last_tweet: NameError: uninitialized constant ActsAsYaffleTest::Wickwall - test/acts_as_yaffle_test.rb:10:in `test_a_wickwalls_yaffle_text_field_should_be_last_tweet' + /path/to/yaffle/test/acts_as_yaffle_test.rb:10:in `test_a_wickwalls_yaffle_text_field_should_be_last_tweet' - 5 tests, 3 assertions, 0 failures, 2 errors, 0 skips + 4 runs, 2 assertions, 0 failures, 2 errors, 0 skips ``` This tells us that we don't have the necessary models (Hickwall and Wickwall) that we are trying to test. @@ -208,17 +214,16 @@ test/dummy directory: ```bash $ cd test/dummy -$ rails generate model Hickwall last_squawk:string -$ rails generate model Wickwall last_squawk:string last_tweet:string +$ bin/rails generate model Hickwall last_squawk:string +$ bin/rails generate model Wickwall last_squawk:string last_tweet:string ``` Now you can create the necessary database tables in your testing database by navigating to your dummy app -and migrating the database. First +and migrating the database. First, run: ```bash $ cd test/dummy -$ rake db:migrate -$ rake db:test:prepare +$ bin/rake db:migrate ``` While you are here, change the Hickwall and Wickwall models so that they know that they are supposed to act @@ -239,7 +244,7 @@ end ``` -We will also add code to define the acts_as_yaffle method. +We will also add code to define the `acts_as_yaffle` method. ```ruby # yaffle/lib/yaffle/acts_as_yaffle.rb @@ -265,22 +270,22 @@ You can then return to the root directory (`cd ../..`) of your plugin and rerun ``` 1) Error: - test_a_hickwalls_yaffle_text_field_should_be_last_squawk(ActsAsYaffleTest): - NoMethodError: undefined method `yaffle_text_field' for #<Class:0x000001016661b8> - /Users/xxx/.rvm/gems/ruby-1.9.2-p136@xxx/gems/activerecord-3.0.3/lib/active_record/base.rb:1008:in `method_missing' - test/acts_as_yaffle_test.rb:5:in `test_a_hickwalls_yaffle_text_field_should_be_last_squawk' + ActsAsYaffleTest#test_a_hickwalls_yaffle_text_field_should_be_last_squawk: + NoMethodError: undefined method `yaffle_text_field' for #<Class:0x007fd105e3b218> + activerecord (4.1.5) lib/active_record/dynamic_matchers.rb:26:in `method_missing' + /path/to/yaffle/test/acts_as_yaffle_test.rb:6:in `test_a_hickwalls_yaffle_text_field_should_be_last_squawk' 2) Error: - test_a_wickwalls_yaffle_text_field_should_be_last_tweet(ActsAsYaffleTest): - NoMethodError: undefined method `yaffle_text_field' for #<Class:0x00000101653748> - Users/xxx/.rvm/gems/ruby-1.9.2-p136@xxx/gems/activerecord-3.0.3/lib/active_record/base.rb:1008:in `method_missing' - test/acts_as_yaffle_test.rb:9:in `test_a_wickwalls_yaffle_text_field_should_be_last_tweet' + ActsAsYaffleTest#test_a_wickwalls_yaffle_text_field_should_be_last_tweet: + NoMethodError: undefined method `yaffle_text_field' for #<Class:0x007fd105e409c0> + activerecord (4.1.5) lib/active_record/dynamic_matchers.rb:26:in `method_missing' + /path/to/yaffle/test/acts_as_yaffle_test.rb:10:in `test_a_wickwalls_yaffle_text_field_should_be_last_tweet' - 5 tests, 3 assertions, 0 failures, 2 errors, 0 skips + 4 runs, 2 assertions, 0 failures, 2 errors, 0 skips ``` -Getting closer... Now we will implement the code of the acts_as_yaffle method to make the tests pass. +Getting closer... Now we will implement the code of the `acts_as_yaffle` method to make the tests pass. ```ruby # yaffle/lib/yaffle/acts_as_yaffle.rb @@ -304,10 +309,10 @@ end ActiveRecord::Base.send :include, Yaffle::ActsAsYaffle ``` -When you run `rake` you should see the tests all pass: +When you run `rake`, you should see the tests all pass: ```bash - 5 tests, 5 assertions, 0 failures, 0 errors, 0 skips + 4 runs, 4 assertions, 0 failures, 0 errors, 0 skips ``` ### Add an Instance Method @@ -321,7 +326,7 @@ To start out, write a failing test that shows the behavior you'd like: # yaffle/test/acts_as_yaffle_test.rb require 'test_helper' -class ActsAsYaffleTest < Test::Unit::TestCase +class ActsAsYaffleTest < ActiveSupport::TestCase def test_a_hickwalls_yaffle_text_field_should_be_last_squawk assert_equal "last_squawk", Hickwall.yaffle_text_field @@ -381,10 +386,14 @@ ActiveRecord::Base.send :include, Yaffle::ActsAsYaffle Run `rake` one final time and you should see: ``` - 7 tests, 7 assertions, 0 failures, 0 errors, 0 skips + 6 runs, 6 assertions, 0 failures, 0 errors, 0 skips ``` -NOTE: The use of `write_attribute` to write to the field in model is just one example of how a plugin can interact with the model, and will not always be the right method to use. For example, you could also use `send("#{self.class.yaffle_text_field}=", string.to_squawk)`. +NOTE: The use of `write_attribute` to write to the field in model is just one example of how a plugin can interact with the model, and will not always be the right method to use. For example, you could also use: + +```ruby +send("#{self.class.yaffle_text_field}=", string.to_squawk) +``` Generators ---------- @@ -392,7 +401,7 @@ Generators Generators can be included in your gem simply by creating them in a lib/generators directory of your plugin. More information about the creation of generators can be found in the [Generators Guide](generators.html) -Publishing your Gem +Publishing Your Gem ------------------- Gem plugins currently in development can easily be shared from any Git repository. To share the Yaffle gem with others, simply @@ -405,12 +414,12 @@ gem 'yaffle', git: 'git://github.com/yaffle_watcher/yaffle.git' After running `bundle install`, your gem functionality will be available to the application. When the gem is ready to be shared as a formal release, it can be published to [RubyGems](http://www.rubygems.org). -For more information about publishing gems to RubyGems, see: [Creating and Publishing Your First Ruby Gem](http://blog.thepete.net/2010/11/creating-and-publishing-your-first-ruby.html) +For more information about publishing gems to RubyGems, see: [Creating and Publishing Your First Ruby Gem](http://blog.thepete.net/2010/11/creating-and-publishing-your-first-ruby.html). RDoc Documentation ------------------ -Once your plugin is stable and you are ready to deploy do everyone else a favor and document it! Luckily, writing documentation for your plugin is easy. +Once your plugin is stable and you are ready to deploy, do everyone else a favor and document it! Luckily, writing documentation for your plugin is easy. The first step is to update the README file with detailed information about how to use your plugin. A few key things to include are: @@ -424,12 +433,12 @@ Once your README is solid, go through and add rdoc comments to all of the method Once your comments are good to go, navigate to your plugin directory and run: ```bash -$ rake rdoc +$ bin/rake rdoc ``` ### References * [Developing a RubyGem using Bundler](https://github.com/radar/guides/blob/master/gem-development.md) * [Using .gemspecs as Intended](http://yehudakatz.com/2010/04/02/using-gemspecs-as-intended/) -* [Gemspec Reference](http://docs.rubygems.org/read/chapter/20) +* [Gemspec Reference](http://guides.rubygems.org/specification-reference/) * [GemPlugins: A Brief Introduction to the Future of Rails Plugins](http://www.intridea.com/blog/2008/6/11/gemplugins-a-brief-introduction-to-the-future-of-rails-plugins) |