Rails Internals
Structure and internals of Ruby on Rails. Learn how to peek under the covers of your framework.
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Understanding the Structure of Rails
Before digging into Rails' own code, it's important to know how the library is structured. The Rails gem has a number of sub-gems that you should know by name…
Where Do I Put My Code in Rails?
Rails is an MVC framework, but not every piece of code is a model, a view or a controller. What kind of code goes in what directories? What types of objects hold each one?
How Does Rack Parse Query Params?
You may know that Rails will parse your query parameters for you - including parameter names like a[] which can automatically create arrays. How does Rails do that? Where does the code live?
Understanding HashWithIndifferentAccess
Rails' params object is a little unusual. You can say param[:foo] or params['foo'] and both work. How does it do that?