class Rails::Generators::Base
Inherits From
-
class
Thor::
Group -
module
Thor::
Actions -
module
Rails::
Generators:: Actions
Public class methods
Small macro to add ruby as an option to the generator with proper default value plus an instance helper method called shebang.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 396
def self.add_shebang_option! # :doc:
class_option :ruby, type: :string, aliases: "-r", default: Thor::Util.ruby_command,
desc: "Path to the Ruby binary of your choice", banner: "PATH"
no_tasks {
define_method :shebang do
@shebang ||= begin
command = if options[:ruby] == Thor::Util.ruby_command
"/usr/bin/env #{File.basename(Thor::Util.ruby_command)}"
else
options[:ruby]
end
"#!#{command}"
end
end
}
end
Use Rails default banner.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 329
def self.banner # :doc:
"bin/rails generate #{namespace.delete_prefix("rails:")} #{arguments.map(&:usage).join(' ')} [options]".gsub(/\s+/, " ")
end
Sets the base_name
taking into account the current class namespace.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 334
def self.base_name # :doc:
@base_name ||= if base = name.to_s.split("::").first
base.underscore
end
end
Returns the base root for a common set of generators. This is used to dynamically guess the default source root.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 236
def self.base_root
__dir__
end
Returns default aliases for the option name given doing a lookup in Rails::Generators.aliases.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 357
def self.default_aliases_for_option(name, options) # :doc:
default_for_option(Rails::Generators.aliases, name, options, options[:aliases])
end
Returns default for the option name given doing a lookup in config.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 362
def self.default_for_option(config, name, options, default) # :doc:
if generator_name && (c = config[generator_name.to_sym]) && c.key?(name)
c[name]
elsif base_name && (c = config[base_name.to_sym]) && c.key?(name)
c[name]
elsif config[:rails].key?(name)
config[:rails][name]
else
default
end
end
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 422
def self.default_generator_root # :doc:
path = File.expand_path(File.join(base_name, generator_name), base_root)
path if File.exist?(path)
end
Returns the default source root for a given generator. This is used internally by Rails to set its generators source root. If you want to customize your source root, you should use source_root.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 227
def self.default_source_root
return unless base_name && generator_name
return unless default_generator_root
path = File.join(default_generator_root, "templates")
path if File.exist?(path)
end
Returns the default value for the option name given doing a lookup in Rails::Generators.options.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 351
def self.default_value_for_option(name, options) # :doc:
default_for_option(Rails::Generators.options, name, options, options[:default])
end
Tries to get the description from a USAGE file one folder above the source root otherwise uses a default description.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 41
def self.desc(description = nil)
return super if description
@desc ||= if usage_path
ERB.new(File.read(usage_path)).result(binding)
else
"Description:\n Create #{base_name.humanize.downcase} files for #{generator_name} generator."
end
end
Removes the namespaces and get the generator name. For example, Rails::Generators::ModelGenerator will return “model” as generator name.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 342
def self.generator_name # :doc:
@generator_name ||= if generator = name.to_s.split("::").last
generator.delete_suffix!("Generator")
generator.underscore
end
end
Convenience method to hide this generator from the available ones when running rails generator command.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 61
def self.hide!
Rails::Generators.hide_namespace(namespace)
end
Invoke a generator based on the value supplied by the user to the given option named “name”. A class option is created when this method is invoked and you can set a hash to customize it.
Examples
module Rails::Generators
class ControllerGenerator < Base
hook_for :test_framework, aliases: "-t"
end
end
The example above will create a test framework option and will invoke a generator based on the user supplied value.
For example, if the user invoke the controller generator as:
$ bin/rails generate controller Account --test-framework=test_unit
The controller generator will then try to invoke the following generators:
"rails:test_unit", "test_unit:controller", "test_unit"
Notice that “rails:generators:test_unit” could be loaded as well, what Rails looks for is the first and last parts of the namespace. This is what allows any test framework to hook into Rails as long as it provides any of the hooks above.
Options
The first and last part used to find the generator to be invoked are guessed based on class invokes hook_for
, as noticed in the example above. This can be customized with two options: :in
and :as
.
Let’s suppose you are creating a generator that needs to invoke the controller generator from test unit. Your first attempt is:
class AwesomeGenerator < Rails::Generators::Base
hook_for :test_framework
end
The lookup in this case for test_unit as input is:
"test_unit:awesome", "test_unit"
Which is not the desired lookup. You can change it by providing the :as
option:
class AwesomeGenerator < Rails::Generators::Base
hook_for :test_framework, as: :controller
end
And now it will look up at:
"test_unit:controller", "test_unit"
Similarly, if you want it to also look up in the rails namespace, you just need to provide the :in
value:
class AwesomeGenerator < Rails::Generators::Base
hook_for :test_framework, in: :rails, as: :controller
end
And the lookup is exactly the same as previously:
"rails:test_unit", "test_unit:controller", "test_unit"
Switches
All hooks come with switches for user interface. If you do not want to use any test framework, you can do:
$ bin/rails generate controller Account --skip-test-framework
Or similarly:
$ bin/rails generate controller Account --no-test-framework
Boolean hooks
In some cases, you may want to provide a boolean hook. For example, webrat developers might want to have webrat available on controller generator. This can be achieved as:
Rails::Generators::ControllerGenerator.hook_for :webrat, type: :boolean
Then, if you want webrat to be invoked, just supply:
$ bin/rails generate controller Account --webrat
The hooks lookup is similar as above:
"rails:generators:webrat", "webrat:generators:controller", "webrat"
Custom invocations
You can also supply a block to hook_for
to customize how the hook is going to be invoked. The block receives two arguments, an instance of the current class and the class to be invoked.
For example, in the resource generator, the controller should be invoked with a pluralized class name. But by default it is invoked with the same name as the resource generator, which is singular. To change this, we can give a block to customize how the controller can be invoked.
hook_for :resource_controller do |instance, controller|
instance.invoke controller, [ instance.name.pluralize ]
end
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 174
def self.hook_for(*names, &block)
options = names.extract_options!
in_base = options.delete(:in) || base_name
as_hook = options.delete(:as) || generator_name
names.each do |name|
unless class_options.key?(name)
defaults = if options[:type] == :boolean
{}
elsif [true, false].include?(default_value_for_option(name, options))
{ banner: "" }
else
{ desc: "#{name.to_s.humanize} to be invoked", banner: "NAME" }
end
class_option(name, defaults.merge!(options))
end
klass = self
singleton_class.define_method("#{name}_generator") do
value = class_options[name].default
Rails::Generators.find_by_namespace(klass.generator_name, value)
end
hooks[name] = [ in_base, as_hook ]
invoke_from_option(name, options, &block)
end
end
Convenience method to get the namespace from the class name. It’s the same as Thor default except that the Generator at the end of the class is removed.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 54
def self.namespace(name = nil)
return super if name
@namespace ||= super.delete_suffix("_generator").sub(/:generators:/, ":")
end
Remove a previously added hook.
remove_hook_for :orm
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 207
def self.remove_hook_for(*names)
remove_invocation(*names)
names.each do |name|
singleton_class.undef_method("#{name}_generator")
hooks.delete(name)
end
end
Returns the source root for this generator using default_source_root
as default.
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 34
def self.source_root(path = nil)
@_source_root = path if path
@_source_root ||= default_source_root
end
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 414
def self.usage_path # :doc:
paths = [
source_root && File.expand_path("../USAGE", source_root),
default_generator_root && File.join(default_generator_root, "USAGE")
]
paths.compact.detect { |path| File.exist? path }
end
Private instance methods
Takes in an array of nested modules and extracts the last module
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 287
def extract_last_module(nesting) # :doc:
nesting.inject(Object) do |last_module, nest|
break unless last_module.const_defined?(nest, false)
last_module.const_get(nest)
end
end
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 302
def indent(content, multiplier = 2) # :doc:
spaces = " " * multiplier
content.each_line.map { |line| line.blank? ? line : "#{spaces}#{line}" }.join
end
Wrap block with namespace of current application if namespace exists and is not skipped
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 296
def module_namespacing(&block) # :doc:
content = capture(&block)
content = wrap_with_namespace(content) if namespaced?
concat(content)
end
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 312
def namespace # :doc:
Rails::Generators.namespace
end
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 316
def namespaced? # :doc:
!options[:skip_namespace] && namespace
end
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 324
def namespaced_path # :doc:
@namespaced_path ||= namespace_dirs.join("/")
end
Source code GitHub
# File railties/lib/rails/generators/base.rb, line 307
def wrap_with_namespace(content) # :doc:
content = indent(content).chomp
"module #{namespace.name}\n#{content}\nend\n"
end