Ruby on rails Model User investor_or_startup:? - ruby-on-rails

Question

Hello I am new to rails and I'm creating an application to practice and learn. I have a issue which I don't know how to solve.
If I generate a model User and I want to include a section in the model where I name it investor_or_startup. When I create the form for a user to fill it out I want the user to only be able to fill in the blank with the word Investor or Startup. How would I go about this?

Answer 1

You could create a selector field in your form.
I would share some code but I think as a new rails developers, you should get used to reading and understanding the docs, as that is invaluable.
http://guides.rubyonrails.org/form_helpers.html#making-select-boxes-with-ease

Answer 2

Add a validation in your model for that specific attribute, if it's called investor_or_startup, then using validates specify this attribute, use the format option, and optionally you can add a message for the user, like:
class User < ApplicationRecord
validates :investor_or_startup,
format: {
with: /Investor|Startup/,
message: 'Two valid options are Investor or Startup'
}
end
The with option inside format accepts a regular expression, in this case to check for the specific word Investor or (|) Startup, it's case sensitive, so lowercase letters would make an invalid input. If you want to change to case insenstive then consider adding i at the end of your expression, like /investor|startup/i.
The message options accepts an string which you can use to display a message for the user.
You can keep reading about this here.

Answer 3

The most common way of doing thin in rails would be to add a role attribute to your User model. In this case, role replaces start_up_or_investor. You would start by using a migration to add a field called role of type :integer to your users table.
Next you would add the following line to your User model:
enum role: [:investor, :start_up]
You can read more about enum here.
Finally, you can use a select_tag in a Rails form helper to select one of the enum options. There are many ways to use a select_tag with an enum. A quick internet search will reveal many blogs and SO posts on the subject.
Bottom line: I recommend using an enum for this sort of thing.

Answer 4

So you have a User model and that user could possibly be an investor or a startup. To start off you could add some kind of "type" attribute that will query whether the user is a startup or an investor. User.type #=> "startup" or User.type #=> "investor". From there you could set up your form_for user and use a select field that would allow the user to select their value for the type attribute <%= f.select(:type, ...) %>
Like Sam suggested, I encourage you to study the rails guides,(particularly form helpers) to help you understand how a form works.

Answer 5

Adding roles to uses is a common programming problem. There are two decent ways to solve this (and many bad ways).
1. Use an ActiveRecord::Enum
class User < ApplicationRecord
enum role: [:investor, :start_up]
end
An enum is a integer column that maps to specific values. In this case investor = 0, start_up = 1.
To create an input based on this you can use the enum mapping:
<%= f.select(:role, User.roles.keys.map {|role| [role.titleize,role]}) %>
While simple the major limitation is that a user can only ever have one role.
2. Setup a many-to-many association
class User < ApplicationRecord
has_many :user_roles
has_many :roles, through: :user_roles
scope :with_role ->{|*names| joins(:roles).where(name: names) }
def has_role?(name)
roles.where(name: name).exist?
end
end
class UserRole < ApplicationRecord
belongs_to :user
belongs_to :role
end
class Role < ApplicationRecord
has_many :user_roles
has_many :users, through: :user_roles
end
This lets you add and remove roles from a user seperately and often is a better fit for real world use cases. The Rolify gem is an excellent example of this pattern.
To allow a user to select roles you can use a checkbox:
<%= f.collection_check_boxes(:role_ids, Role.all, :id, :name) %>