Add allow_people_to_vote

Author: joelbyler

allow_people_to_vote.md

@@ -0,0 +1,74 @@
+# Allow People To Vote
+
+## Goals
+Now we're going to add a button people can click to cast a vote.
+
+## Steps
+### Step 1: Add a new controller action for voting
+Edit `app/controllers/topics_controller.rb` and add this method at the end of the controller, above the `private` keyword:
+
+```ruby
+def upvote
+  @topic = Topic.find(params[:id])
+  @topic.votes.create
+  redirect_to(topics_path)
+end
+```
+
+* `@topic = Topic.find(params[:id])` finds the topic in the database with that id and stores it in the variable @topic.
+* `@topic.votes.create` creates a new vote for the current topic and saves it in the database.
+* `redirect_to(topics_path)` tells the browser to go back to `topics_path` (the topics list).
+
+### Step 2: Add a new route for voting
+Open `config/routes.rb` and find the section that looks like this:
+
+```ruby
+resources :topics
+```
+
+Replace that line so it looks like this:
+
+```ruby
+resources :topics do
+  member do
+    post 'upvote'
+  end
+end
+```
+
+Verify that upvote route was added successfully by checking the output of `rake routes`. You should see a line that looks like this:
+
+```bash
+      Prefix Verb   URI Pattern                  Controller#Action
+upvote_topic POST   /topics/:id/upvote(.:format) topics#upvote
+```
+### Step 3: Add the button to the view
+Edit app/views/topics/index.html.erb so that the bottom loop looks like this:
+
+```ruby
+<% @topics.each do |topic| %>
+  <tr>
+    <td><%= topic.title %></td>
+    <td><%= topic.description %></td>
+    <td><%= pluralize(topic.votes.count, "vote") %></td>
+    <td><%= button_to '+1', upvote_topic_path(topic), method: :post %></td>
+    <td><%= link_to 'Show', topic %></td>
+    <td><%= link_to 'Edit', edit_topic_path(topic) %></td>
+    <td><%= link_to 'Destroy', topic, method: :delete, data: { confirm: 'Are you sure?' } %></td>
+  </tr>
+<% end %>
+```
+
+* `pluralize(topic.votes.count, "vote")` displays the number of votes the topic has, plus the word "vote" or "votes" accordingly.
+* `button_to '+1'` creates an HTML button with the text "+1".
+* `upvote_topic_path(topic)` creates the appropriate URL for the action we want to invoke. In this case, we want to upvote the current topic.
+  * `upvote_topic_path(topic)` would return `/topics/42/upvote` (if topic.id was 42)
+* `method: :post` ensures we do the create action of CRUD, not the read action.
+
+### Step 4: Confirm your changes in the browser
+Go back to and refrest the app in the otherweb browser and try out the latest changes.
+
+Revel in the fact that you didn't have to restart the server to see these changes. Hawt, no?
+
+Next Step:
+Go on to [Redirect To The Topics List After Creating A New Topic](redirect_to_the_topics_list_after_creating_a_new_topic.md)

hooking_up_votes_and_topics.md

@@ -99,4 +99,4 @@ Associations (usually) come in pairs.
 It can still be important to clean up after yourself! `dependent: :destroy` on `has_many :votes` means when a __Topic__ gets destroyed, all the __votes__ that correspond to it will be destroyed, too. Without `dependent :destroy`, those votes would live on the database forever.
 
 Next Step:
-Go on to Allow People To Vote
+Go on to [Allow People To Vote](allow_people_to_vote.md)