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
Related
I am trying to use collection_select tag for the default _form.html.erb using a concern/module, I need to set a hash including some department names.
Here is my app/models/concerns/SetDepartment.rb
module Set_Department
extend ActiveSupport :: Concern
def department
department {
1=>"Amatitlán",
2=>"Chinautla",
3=>"Chuarrancho"
}
end
end
Here is the model where I want to call the department method:
class Aplicante < ActiveRecord::Base
include SetDepartment
validates :titulo_id, :primer_nombre,
:primer_apellido, :dpi, :direccion_linea_1,:zona, :department_id, :username,
presence: true
validates :dpi,:username, uniqueness: true
has_secure_password
end
Now, I need to include this hash in a collection_select tag on my app/views/applicants/_form.html.erb
#...
<div class="field">
<%= f.label :department_id %><br>
<%= f.collection_select :department_id, Aplicante.department, Aplicante.department %>
</div>
#...
Obviously, this does not work but I can not think on anything else.
I have searched through the internet but I just get tough explinations and none of them involves a module... is it even possible?
Solved!
I was using the wrong method..
We can not use a collection_select helper with a hash, instead, we need to use the regular select method.
Collection_select is used when you have two models and you want to combine their different values in a drop down menu.
Information about how to use the select tag with a hash here:
http://apidock.com/rails/ActionView/Helpers/FormTagHelper/select_tag
First question: how to validate a model relation and mark it in form when validation failed.
I have a subject model:
class Subject < ActiveRecord::Base
belongs_to :semester
validates_presence_of :semester
end
In my view (form):
<%= select_tag :semester, options_from_collection_for_select(#semesters,"id","name") %>
The validates_presence_of works fine. But when the validation fails (user forgot to enter semester ). The semester input is not marked in red.
Second question: how to validate an input field.
In my view, I also have a university input field, but model subject has no relationship with university, no field university in subject table. So how to validate it and mark it in red.
Thanks in advance.
If you want to get the fields with error displayed in red "out of the box", you must use a form builder. The code will looks like f.select ... instead of using select_tag.
With the form builder, the fields with errors are created inside a <div class="field_with_errors">...</div>. The css file generated by scaffolding displays these fields in red; if you're not using it, you must add the css rules to your css.
# app/models/subject.rb
class Subject < ActiveRecord::Base
belongs_to :semester
validates :semester, :university, presence: true # new syntax http://api.rubyonrails.org/classes/ActiveModel/Validations/ClassMethods.html#method-i-validates
end
# app/views/subjects/_form.html.erb
<%= form_for #subject do |f| %>
Semestr: <%= f.collection_select :semester_id, Semestr.all, :id, :name, prompt: true %>
University: <%= f.text_field :univercity %>
<% end %>
For more information about building forms in rails (with validations enabled) you could find there http://api.rubyonrails.org/classes/ActionView/Helpers/FormBuilder.html
Those "red errors" that you hope for are probably coming from a form helper gem like formtastic, feel free to check that out.
I have literally no idea what your second question is asking, but if you're looking for a custom validation. Check out the rails docs on them for help.
If you'd like more help, (please) edit your question to be more clear (thanks)
How do you simply validate that a checkbox is checked in rails?
The checkbox is for a end user agreement. And it is located in a modal window.
Lets say i have the checkbox:
<%= check_box_tag '' %>
Where and how should i validate this?
I have seen most posts about checkbox validation in rails here, but none of them suit my needs.
Adding
validates :terms_of_service, :acceptance => true
to your model should do it. Look here for more details and options.
However, if accepting the terms is not part of a form for your model, you should use client-side validations, i.e. JavaScript, like this (in jQuery):
function validateCheckbox()
{
if( $('#checkbox').attr('checked')){
alert("you have to accept the terms first");
}
}
You can add a script file to your view like this:
<%= javascript_include_tag "my_javascipt_file" %>
and trigger the function on click:
<%= submit_tag "Submit", :onclick: "validateCheckbox();" %>
EDIT: you can assign an id to your checkbox like this: check_box_tag :checkbox. The HTML will look like this: <input id="checkbox" See these examples for more options.
I was able to skip the jQuery portion and get it validation to work with this questions help. My method is below, I'm on Rails 5.1.2 & Ruby 2.4.2.
Put this code in your slim, erb or haml; note syntax may differ slightly in each.
The line below was specifically for slim.
f.check_box :terms_of_service, required: true
I used a portion of kostja's code suggestion in the model.
validates :terms_of_service, :acceptance => true
Adding on to what has been said already, if you want to add a custom error message, you can add the following to your form:
f.input :terms_of_service, as: :boolean
and then add the following to your model:
validates :terms_of_service, acceptance: { message: "must be accepted"}
Error messages will start with the field name by default followed by your custom message (e.g. Terms of service [CUSTOM MESSAGE]). Something I also found useful was to include a link to the terms of service in the label so users can easily access it to see what they are agreeing to:
f.input :terms_of_service, as: :boolean, label: "I agree to the #{link_to "terms of service", [TERMS AND CONDITIONS PATH]}".html_safe
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