Is there a rails way to titleize and humanize strings before storing into database

Question

The problem about humanize (and probably titleize too i'm not sure) is that it breaks the view if the string is nil . and then you'll have to .try(:humanize) instead, which is a big headache if you realized that you made that mistake way too late and you have to recheck every line of code at your views. What i'm looking for is a way i could humanize and titleize strings before storing them into the database. That way, even if i'm looking straight into my database i will see the strings humanize d and titleize d.

Answer 1

You can create a method in your model which will take the attributes of this, and will transform as you want and/or you need, you can "fire" this every time you save a record using it as a before_save callback:

For instance, having a model User which attributes name and lastname I'm using the name and using titleize on it:

class User < ApplicationRecord
  before_save :titlelize_names

  def titlelize_names
    self.name = self.name.titleize
  end
end

The params will contain the attributes as the user has typed them, but they will be saved according to what the model says:

Processing by UsersController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"...", "user"=>{"name"=>"name", "lastname"=>"lastname"}, "commit"=>"Create User"}
(0.1ms)  begin transaction
SQL (0.8ms)  INSERT INTO "users" ("name", "lastname", "created_at", "updated_at") VALUES (?, ?, ?, ?)  [["name", "Name"], ["lastname", "lastname"]...]

Is the only one interaction you need to do before save the record, the view is untouched and the controller just receive it and makes what model says.

If by any change it occurs some problem at the moment of saving the record you can use throw(:abort) and "to force to halt" the callback chain.

def titlelize_names
  self.name = self.name.titleize
  throw(:abort)
end

In addition and depending on which method you're using with the before_save callback, you can add custom errors which will be available to use within your controllers, as for instance, an error identified by the key :titleize_names could be then handled in the controller.

def titlelize_names
  errors.add(:titleize_names, 'An error has ocurred with the name attribute.')
  self.name = self.name.titleize
  throw(:abort)
end

Answer 2

You can use model callbacks to transform the data before saving it to the DB: http://api.rubyonrails.org/classes/ActiveRecord/Callbacks.html - you probably want before_save .

Also, if you want to ensure the record is never nil, add a validation as well.

Example:

class Example < ActiveRecord::Base
  validates :name, presence: true
  before_save :fixname

  # Force titleize on :name attribute
  def fixname
    self.name = self.name.titleize
  end
end

Now your model will have a method called fixname that you can call anywhere on your model instance as well as having it called before saving it to the DB.

Answer 3

如果humanize和titlerize如果值是零返回例外，if语句创建一个，你可以使用一个服务或一个函数模型，使这个过程before_save或before_create回调：

value.titleize unless value.nil?