I was just wondering: How can i make an attribute "write once" ?
To be more precise, I'm using Devise and I want the user to be able to register with this email but then, once it's done, I want this email locked.
I read that forms can easily be bypass, so I want to make sure my model does that.
Also, i'm using in one of my form that: <%= f.email_field :email, :id => "email", :disabled => "disabled" %>
Is there any risks that an user can modify his email after being registered?
Thanks for your answers!
attr_readonly allows setting a value at creation time, then prevents modifying it on updates.
class MyModel < ActiveRecord::Base
attr_readonly :email
end
Related
I have a form and I have made some inputs required. After submitting the form that value will be sent to an API. I know that the validations are put into model file but since I do not have a database, how can I use the rails validation?
Right now I am validating the code inside a controller using if else.
if !params[:groups][:name].blank? && !params[:groups][:make].blank? && !params[:groups][:model].blank? && !params[:groups][:firmware].blank?
This does the work but it is not very elegant.
Take a look at ActiveModel, it lets you do "model things" without the database. There were some limitations that made me not use it in the end (I think related to associations) but for simple stuff it's great (and it's a part of how ActiveRecord works.
Example code from docs
class Person
include ActiveModel::Model
attr_accessor :name, :age
validates :name, :age, presence: true
end
this is easy. On the form input fields that you NEED, add required: true For example:
<%= form.for #something do |f| %>
<%= f.text_field :title, placeholder: 'Title', required: true %>
<% end %>
The user gets an error if the required fields are not filled out correctlty.
Is this what you mean?
Justin
EDIT
I guess I would look at using the gem
client_side_validations
Let us know how you go
I have a "Word" model that has 3 string variables: "word_a" , "word_b" , "word_ab".
A form in my view collects the values for "word_a" and "word_b":
<%= f.text_field :word_a %>
<%= f.text_field :word_b %>
What is the best way to save the value for "word_ab" which will be made automatically from a combo of "word_a" and "word_b"?
The way Im doing it now seems really really wrong. After submitting the first form, I have the controller redirect to another edit page with a 'word_ab' form that has a value that combines 'word_a' and 'word_b'.
<%= f.text_field :word_ab, :value => #word.word_a+"_"+#word.word_b %>
The user then has to resubmit the form to save 'word_ab' into the database. Can't I do this is a controller?
Are you sure you want to save concated value to db? What about editing?
If you still want to do it - best idea is to add attr_accessor in model
attr_accessible :word_a, :word_b
attr_accessor :word_a, :word_b
First line allows yo perform mass assign, second one creates setter and getter methods.
Then, still in a model do
before_validation(:on => :create) do
self.word_ab = word_a + word_b
end
You may perform this on before_save as well, and you may validate word_a and word_b separately with regular validators.
Pro tip: create getter method that returns concated string
def word_ab
self.word_a + self.word_b
end
Associated models
class User
has_one :profile_picture
def word_ab
self.profile_picture.url + self.word_a + self.word_b
end
end
Say I have two fields in a new or edit form:
<%= f.text_field :email %>
<%= f.text_field :parent_email %>
How, in my model, can I validate that parent_email is different from email? The exclusion option seems like it might work, but I can't figure out how to access the email field's value within the model. Do I need to implement this in the controller instead?
validates :parent_email, exclusion: self.email # doesn't work, nor does :email
The following should work (but I guess there are cooler solutions out there):
class User
validate :email_differs_from_parent_email
private
def email_differs_from_parent_email
if email == parent_email
errors.add(:parent_email, "parent_email must differ from email")
end
end
end
I have a Rails model (persisted with Mongoid) that can be collaboratively edited by any registered user. However, I want to allow editing any particular attribute only if it was previously blank or nil.
For example, say someone created an object, and set its title attribute to "Test Product". Then another user comes along and wants to add a value for price, which until now has been nil.
What's the best way to do this, while locking an attribute that has previously been entered?
Look into the ActiveRecord::Dirty module for some nice utility methods you can use to do something like this:
NON_UPDATABLE_ATTRIBUTES = [:name, :title, :price]
before_validation :check_for_previously_set_attributes
private
def check_for_previously_set_attributes
NON_UPDATABLE_ATTRIBUTES.each do |att|
att = att.to_s
# changes[att] will be an array of [prev_value, new_value] if the attribute has been changed
errors.add(att, "cannot be updated because it has previously been set") if changes[att] && changes[att].first.present?
end
end
The easiest way, i think, is by checking for it in the form itself.
Just say add :disabled => true to the input field if the person cannot edit it.
<% if #my_object.name %>
<%= f.text_field :name, :disabled => true %>
<% else %>
<%= f.text_field :name, :disabled => true %>
<% end %>
(i think there is a prettier way to write this code)
But by using this the user has a visual feed back that he can't do something, it is always better to not allor something than to give an error message
I used declarative_authorization for my app and had problem with creating new user.
my User model code:
class User < ActiveRecord::Base
ROLE_TYPES = ["admin", "user", "guest"]
validates_inclusion_of :roles, :in => ROLE_TYPES
def role_symbols
#role_symbols ||= (roles || []).map{|r| r.to_sym}
end
my view code:
<% form_for(#user) do |f| %>
...
<p>
<%= f.label :roles %><br />
<%= f.select :roles, User::ROLE_TYPES, :prompt => "Select a role" %>
</p>
<%= f.submit 'Add User' %>
<% end %>
every time i tried to create a new user and select the role from the drop-down list, the view complaint:
Roles is not included in the list
from the output of the script/server, i can see the roles was actually set:
"user"=>{"name"=>"kc", "password_confirmation"=>"kc", "roles"=>"guest", "password"=>"kc", "email"=>"kc#one.com"}
can anyone tell me what's wrong? why the validation wont' pass?
Is it possible that you've got attr_accessible attributes on the user to prevent mass assignment of certain attributes and that :roles isn't in there? You would get a warning about this in your logs though. The default User class generated by restful_authentication does include the attr_accessible call so it may be there without you having added it if you are using that authentication plugin too.
Is there definitely a roles attribute of the right type for users? It looks like you're expecting roles to be a single string from your form but in the code from declarative_authorization you've got (roles || []).map which suggests that that part of the code at least is expecting an array of roles.