Update Getting Started Guide - Strong Parameters [ci skip]

	modified:   guides/source/getting_started.md

guides/source/getting_started.md

@@ -531,21 +531,28 @@ and change the `create` action to look like this:
 
 ```ruby
 def create
-  @post = Post.new(params[:post])
-
+  @post = Post.new(post_params)
+ 
   @post.save
-  redirect_to @post 
+  redirect_to @post
 end
+
+private
+  def post_params
+    params.require(:post).permit(:title, :text)
+  end
 ```
 
 Here's what's going on: every Rails model can be initialized with its
 respective attributes, which are automatically mapped to the respective
 database columns. In the first line we do just that (remember that
-`params[:post]` contains the attributes we're interested in). Then,
+`post_params` contains the attributes we're interested in). Then,
 `@post.save` is responsible for saving the model in the database.
 Finally, we redirect the user to the `show` action,
 which we'll define later.
 
+TIP: Note that `def post_params` is private. This new approach prevents an attacker from setting the model's attributes by manipulating the hash passed to the model. For more information, refer to [this blog post about Strong Parameters](http://weblog.rubyonrails.org/2012/3/21/strong-parameters/).
+
 TIP: As we'll see later, `@post.save` returns a boolean indicating
 whether the model was saved or not.