Why doesn't article.tag_list display the tags?

Question

I have added gem 'acts-as-taggable-on' -v 2.3.1 in Gemfile. Rails version 3.2.13, Ruby -v 1.9.3

In article.rb,

class Article < ActiveRecord::Base
  acts_as_taggable_on :tags
  has_many :comments, dependent: :destroy

  validates :title, presence: true,
                length: { minimum: 5 }
end

In articles_controller.rb,

class ArticlesController < ApplicationController

before_filter :authenticate_author!, except: [:index, :show]

def index
  myarray = Article.all
  @articles = Kaminari.paginate_array(myarray).page(params[:page]).per(10)
end

def show
  @article = Article.find(params[:id])
end

def new
  @article = Article.new
end

def create
  @article = Article.new(article_params)

  if @article.save
    redirect_to @article
  else
    render 'new'
  end
end

def edit
  @article = Article.find(params[:id])
end

def update
  @article = Article.find(params[:id])

  if @article.update_attributes(article_params)
    redirect_to @article
  else
    render 'edit'
  end
end

def destroy
  @article = Article.find(params[:id])
  @article.destroy

  redirect_to articles_path
end

private

def article_params
  params.require(:article).permit(:title, :text, :tag_list => [])
end

end

In articles/_form.html.erb

<div class="field">
  <%= f.label :tag_list, "Tags (separated by commas)" %><br />
  <%= f.text_field :tag_list %>
</div>

I ran the following commands after installing the acts-on-taggable-gem,

rails generate acts_as_taggable_on:migration
rake db:migrate

In articles/index.html.erb

<% @articles.each do |article| %>
  <tr>
    <td><%= article.title %></td>
    <td><%= article.text %></td>
    <td><%= article.tag_list %></td>
    <td><%= link_to 'Show', article_path(article) %></td>
    <% if author_signed_in? %> 
      <td><%= link_to 'Edit', edit_article_path(article) %></td>
      <td><%= link_to 'Destroy', article_path(article),
            method: :delete,
            data: { confirm: 'Are you sure?' } %></td>
    <% end%>
  </tr>
<% end %>

The tags are not being displayed in the index page. But if I do ,

article = Article.new(:title => "Awesome")
article.tag_list = "awesome, cool"
article.save

The transaction gets committed and the tags are displayed on the browser.

Why aren't the tags getting saved and displayed in the index page?

Answer 1

The Tag List is an array, which means you need to 'loop' to extract the data. Whenever I have used acts_as_taggable I run through a loop to extract the tags. Something like the following should work:

<% @articles.each do |article| %>
  <tr>
    <td><%= article.title %></td>
    <td><%= article.text %></td>

    <td>
        <% article.tag_list.each do |tag| %>
                <%= tag %>
        <% end %>
    </td>

    <td><%= link_to 'Show', article_path(article) %></td>
    <% if author_signed_in? %> 
      <td><%= link_to 'Edit', edit_article_path(article) %></td>
      <td><%= link_to 'Destroy', article_path(article),
            method: :delete,
            data: { confirm: 'Are you sure?' } %></td>
    <% end%>
  </tr>
<% end %>