Display ~username from asciicast if no profile assigned

app/helpers/asciicasts_helper.rb

@@ -19,6 +19,12 @@ module AsciicastsHelper
       end
 
       link_to img + "~#{asciicast.user.nickname}", profile_path(asciicast.user)
+    else
+      if asciicast.username.present?
+        "~#{asciicast.username}"
+      else
+        "anonymous"
+      end
     end
   end
 

app/models/asciicast.rb

@@ -24,6 +24,7 @@ class Asciicast < ActiveRecord::Base
   def meta=(file)
     data = JSON.parse(file.tempfile.read)
 
+    self.username         = data['username']
     self.user_token       = data['user_token']
     self.duration         = data['duration']
     self.recorded_at      = data['recorded_at']

db/migrate/20120403165915_add_username_to_asciicast.rb

@@ -0,0 +1,5 @@
+class AddUsernameToAsciicast < ActiveRecord::Migration
+  def change
+    add_column :asciicasts, :username, :string
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20120311142204) do
+ActiveRecord::Schema.define(:version => 20120403165915) do
 
   create_table "asciicasts", :force => true do |t|
     t.integer  "user_id"
@@ -33,6 +33,7 @@ ActiveRecord::Schema.define(:version => 20120311142204) do
     t.string   "user_token"
     t.text     "description"
     t.boolean  "featured",         :default => false
+    t.string   "username"
   end
 
   add_index "asciicasts", ["created_at"], :name => "index_asciicasts_on_created_at"