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Crafting Rails 4 Applications, 2nd Edition
book

Crafting Rails 4 Applications, 2nd Edition

by Jose Valim
November 2013
Intermediate to advanced content levelIntermediate to advanced
200 pages
4h 31m
English
Pragmatic Bookshelf
Content preview from Crafting Rails 4 Applications, 2nd Edition

Taking It to the Next Level

In the previous section, we wrote our Mail Form plug-in with some basic features and added integration testing to ensure it works. However, we can do a lot more with Active Model. Let’s look at some examples.

Validators

Every Rails developer is familiar with Rails validations, as they are often used to exemplify the productivity that can be achieved with Rails. In the Rails source code, each validation is backed up by a validator class. Let’s see the validates_presence_of macro as an example:

rails/activemodel/lib/active_model/validations/presence.rb
 
def​ validates_presence_of(*attr_names)
 
validates_with PresenceValidator, _merge_attributes(attr_names)
 
end

The validates_with method is responsible for initializing ...

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Publisher Resources

ISBN: 9781941222331Errata