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Diffstat (limited to 'guides/source/initialization.md')
| -rw-r--r-- | guides/source/initialization.md | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/guides/source/initialization.md b/guides/source/initialization.md index 91d12b4432..fe6b1ad906 100644 --- a/guides/source/initialization.md +++ b/guides/source/initialization.md @@ -468,14 +468,24 @@ def initialize!(group=:default) #:nodoc: end ``` -As you can see, you can only initialize an app once. This is also where the initializers are run. +As you can see, you can only initialize an app once. The initializers are run through +the `run_initializers` method which is defined in `railties/lib/rails/initializable.rb` -TODO: review this +```ruby +def run_initializers(group=:default, *args) + return if instance_variable_defined?(:@ran) + initializers.tsort_each do |initializer| + initializer.run(*args) if initializer.belongs_to?(group) + end + @ran = true +end +``` -The initializers code itself is tricky. What Rails is doing here is it -traverses all the class ancestors looking for an `initializers` method, -sorting them and running them. For example, the `Engine` class will make -all the engines available by providing the `initializers` method. +The run_initializers code itself is tricky. What Rails is doing here is +traversing all the class ancestors looking for those that respond to an +`initializers` method. It then sorts the ancestors by name, and runs them. +For example, the `Engine` class will make all the engines available by +providing an `initializers` method on them. The `Rails::Application` class, as defined in `railties/lib/rails/application.rb` defines `bootstrap`, `railtie`, and `finisher` initializers. The `bootstrap` initializers |