Question

Simple rails app: I have 2 models, user and intro [which is simply a message]. Each message has a sender (user) and receiver (user). Here’s the intro model (validations omitted):

class Intro < ActiveRecord::Base
  attr_accessible :content

  belongs_to :sender, class_name: "User"
  belongs_to :receiver, class_name: "User"

  default_scope order: 'intros.created_at DESC'
end

and now the user model:

class User < ActiveRecord::Base
    attr_accessible :name, :email, :password, :password_confirmation
    has_secure_password

    has_many :sent_intros, foreign_key: "sender_id", dependent: :destroy, class_name: "Intro"
    has_many :received_intros, foreign_key: "receiver_id", dependent: :destroy, class_name: "Intro"

    before_save { |user| user.email = email.downcase }
    before_save :create_remember_token

    private

        def create_remember_token
            self.remember_token = SecureRandom.urlsafe_base64
        end
end

The app currently lets the current user submit an intro into a form and associate with that message (a home page shows sent_intros). However, I could use some help in the intros_controller/create method when it comes to the received_intros function. How do I let an intro that is created by the current user be associated with (i.e. sent to) another specific user so that I can route it to a recipient’s inbox? Thank you.

class IntrosController < ApplicationController
  before_filter :signed_in_user

  def create
    @sent_intro = current_user.sent_intros.build(params[:intro])
    if @sent_intro.save
        flash[:success] = "Intro sent!"
        redirect_to root_path
    else
        render 'static_pages/home'
    end
  end

  def index
  end

  def destroy
  end
end

Answer 1

It doesn’t look like you’re allowing the current_user to assign a receiver to an intro they create? You need to have an input on your form that allows a user to set a valid receiver_id, and you need to add receiver_id to attr_accessible:

class Intro < ActiveRecord::Base
  attr_accessible :content, :receiver_id 

  #Rest of your code
end

With that, when your intro is created, it will be properly associated with both a sender and a receiver. You would then be able to access a current_user’s received intros with the method current_user.received_intros

You may want to add some validation to the Intro model to make sure both a receiver and a sender exist.

EDIT: You can add the receiver_id field to your code in the comments like so:

<!-- In your first view -->
<% provide(:title, 'All users') %> 
<h1>All users</h1> 
<%= will_paginate %> 
<ul class="users"> 
  <%= @users.each do |user| %> 
    <%= render user %> 
    <%= render 'shared/intro_form', :user => user %>  <!-- make sure you pass the user to user intro_form -->
  <% end %> 
</ul> 
<%= will_paginate %> 

<!-- shared/intro_form -->
<%= form_for(@sent_intro) do |f| %> 
  <%= render 'shared/error_messages', object: f.object %> 
  <div class="field">  
    <%= f.text_area :content, placeholder: "Shoot them an intro..." %> 
  </div> 
  <%= observe_field :intro_content, :frequency => 1, :function => "$('intro_content').value.length" %> 
  <%= f.hidden_field :receiver_id, :value => user.id %> <!-- Add this to pass the right receiver_id to the controller -->
  <%= f.submit "Send intro", class: "btn btn-large btn-primary" %> 
<% end %>