Ruby on Rails: Limit user to endorse(comment) 3 other users a month

Question

what I want to do is to let a user endorse 3 other users a month only (and perhaps clear the limit with each new month if possible.

I've tried following this ror limiting users to 2 posts per day

With no luck. I've created the this_month method in my user model

def this_month
   where(:created_at => (Time.zone.now.beginning_of_month..Time.zone.now))
end

and in my Endorsements model:

class Endorsement < ActiveRecord::Base
  belongs_to :endorser, class_name: "User"
  belongs_to :endorsed, class_name: "User"
  validates :endorser_id, presence: true
  validates :endorsed_id, presence: true
  validates :comment, presence: true, length: { maximum: 140}
  validate :endorsement_count_within_limit?, :on => :create

  private
    def endorsement_count_within_limit?
      if endorser.endorsing.this_month.count >= 3
        errors.add(:base, "Exceeded endorse limit (3) this month")
      end
    end

end

And I get an error when trying to endorse

NoMethodError (undefined method `this_month' for #<User::ActiveRecord_Associations_CollectionProxy:0x007fe6bd957fa8>):
  app/models/endorsement.rb:11:in `endorsement_count_within_limit?'
  app/models/user.rb:113:in `endorse'
  app/controllers/endorsements_controller.rb:7:in `create'

What am I missing in here?

This is my user model

class User < ActiveRecord::Base
  has_many :active_endorsements, class_name: "Endorsement",
                                 foreign_key: "endorser_id",
                                 dependent: :destroy
  has_many :passive_endorsements, class_name:  "Endorsement",
                                  foreign_key: "endorsed_id",
                                  dependent:   :destroy
.
.
.
  has_many :endorsing, through: :active_endorsements, source: :endorsed
  has_many :endorsers, through: :passive_endorsements, source: :endorser

  attr_accessor :remember_token, :activation_token, :reset_token
  before_save :downcase_email
  before_create :create_activation_digest
  validates :name, presence: true, length: { maximum: 50}
  VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-]+(\.[a-z\d\-]+)*\.[a-z]+\z/i
  validates :email, presence: true, length: { maximum: 255 },
                    format: { with: VALID_EMAIL_REGEX },
                    uniqueness: { case_sensitive: false }
  has_secure_password
  validates :password, presence: true, length: { minimum: 6 }, allow_nil: true
.
.
.

  # Endorses a user.
  def endorse(other_user, comment)
    active_endorsements.create(endorsed_id: other_user.id, comment: comment)
  end

  # Unendorses a user.
  def unendorse(other_user)
    active_endorsements.find_by(endorsed_id: other_user.id).destroy
  end

  # Returns true if the current user is endorsing the other user.
  def endorsing?(other_user)
    endorsing.include?(other_user)
  end

  def this_month
    where(:created_at => (Time.zone.now.beginning_of_month..Time.zone.now))
  end
  private

.
.
.
end

And endorsement controller:

class EndorsementsController < ApplicationController
  before_action :logged_in_user

  def create
    @user = User.find(params[:endorsed_id])
    comment = params[:endorsement][:comment]
    current_user.endorse(@user, comment)
    respond_to do |format|
      format.html { redirect_to @user }
      format.js
    end
  end

  def destroy
    @user = Endorsement.find(params[:id]).endorsed
    current_user.unendorse(@user)
    respond_to do |format|
      format.html { redirect_to @user }
      format.js
    end
  end

end

I've cut out the unnecessary (i think) things. If needed the rest of the code (without some additions) is present at https://bitbucket.org/kramarz/pracainzynierska

Answer 1

it looks like endorsing is a collection not a single model, so it doesnt have that this_month method that you built on your two models

try changing to

def endorsement_count_within_limit?
  if endorser.endorsing.where(:created_at => (Time.zone.now.beginning_of_month..Time.zone.now)).count >= 3
    errors.add(:base, "Exceeded endorse limit (3) this month")
  end
end

and see if it gets rid of the issue. this might be solvable by defining it as a scope instead of a method

Answer 2

I actually found a reason.

It should look like this in the user model:

has_many :endorsing, through: :active_endorsements, source: :endorsed do
    def this_month
      where(:created_at => (Time.zone.now.beginning_of_month..Time.zone.now))
    end
  end

I was missing the do..end at the other post and placed the method at the end of the model. It seems to work now, produces an error

ArgumentError (First argument in form cannot contain nil or be empty):
  app/views/shared/_unendorse.html.erb:1:in `_app_views_shared__unendorse_html_erb__1506472371249770260_70025812987440'
  app/views/endorsements/create.js.erb:1:in `_app_views_endorsements_create_js_erb__2132303159922640595_70025812908380'
  app/controllers/endorsements_controller.rb:8:in `create'

In the server log. I belive thats a valid error (already got 3 endorsed users) - but how can i display it on the website? So it looks like in the method

"Exceeded endorse limit (3) this month"

instead of what the error produces?

Edit:

I've managed to solve the error displaying correctly :)

It boiled down to have this method in my endorsement model:

  def endorsement_count_within_limit?
    if endorser.endorsing.where(:created_at => (Time.zone.now.beginning_of_month..Time.zone.now)).count >= 3
      errors.add(:base, "Exceeded endorse limit (3) this month")
    end
  end

and having my endorse partial that render the correct form depending if user is endorsing other user or not:

<%= form_for(current_user.active_endorsements.build, remote: true) do |f| %>
  <% if f.object.endorsement_count_within_limit? %>
    <div id="error_explanation">
      <div class="alert alert-danger">
        The form contains <%= pluralize(f.object.errors.count, "error") %>.
      </div>
      <ul>
      <% f.object.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% else %>
    <div><%= hidden_field_tag :endorsed_id, @user.id %></div>
    <%= f.submit "Endorse", class: "btn btn-primary" %>
    <%= f.text_field :comment, class: 'form-control' %>
  <% end %>
<% end %>