Using custom tagging in Rails

Question

I spent a lot of time on this one and now I am stuck. I am currently trying to setup a tagging system in my app. I believe all my associations are correct, however I am having trouble with my views. The tags are being created using their own form. What I want to do is when a user creates a new item, they will be able to choose from a list of tags that they have created from the tag form.

Here are my models:

class Item < ActiveRecord::Base
  attr_accessible :title, :media, :tag_ids
  belongs_to :user
  has_many :taggings, :dependent => :destroy
  has_many :tags, :through => :taggings
end

class Tag < ActiveRecord::Base
  attr_accessible :name
  belongs_to :user
  has_many :taggings, :dependent => :destroy  
  has_many :items, :through => :taggings
end

Here are my views which I know are flawed. Item form:

<%= form_for @item, :html => { :multipart => true } do |f| %>
  <div class="field">
    <%= f.file_field :media %>

    <%= f.text_field :title, placeholder: "Add title..." %>

    <% @tags.each do |tag| %>
        <div>
            <%= check_box_tag "item[tag_ids][]", tag.id, @item.tags.include?(tag) %>
            <%= tag.name %>
        </div>
    <% end %>
</div>

Show item view:

<li>
  <span class="title"><%= item.title %></span>
  <%= image_tag item.media.url(:small) %>
  <span>
    <% @item.tags.each do |tag| %>
      <% tag.name %>
    <% end %>
  </span>
  <span class="timestamp">
    Posted <%= time_ago_in_words(item.created_at) %> ago.
  </span>
  <%= link_to "delete", item, method:  :delete, confirm: "You sure?", title:   item.title %>
</li>

The tags are being created and both items and tags are being attached properly in my taggings database. However, I need help with two things:

1. How do I alter the check_box_tag to only show the tags created by the current user (I am using Devise)?
2. How come no tags show up in the item view?

I'm also new to Rails and want to learn how to do this without a plugin.

Answer 1

I finally figured it out. The show-item code that I posted is actually a partial. In the view that references the partial, I am using <% render @item %>. So in my tag loop, it should be

<span>
  <% item.tags.each do |tag| %>
    ...

not @item.tags.each |tag| %>

Answer 2

1. you can alter the @tags in your controller.

you're probably setting it like this

@tags = Tag.all

Change it to

@tags = current_user.tags

Here I'm presuming that your Devise model is called User. You might also have to take some precautions since you're now showing tags for authenticated users only.

2. you have to replace <% tag.name %> with <%= tag.name %>.