Load asciicast data via ajax

Gemfile

@@ -9,6 +9,7 @@ gem 'confstruct'
 gem 'omniauth'
 gem 'omniauth-twitter'
 gem 'omniauth-github'
+gem 'bzip2-ruby'
 
 # Gems used only for assets and not required
 # in production environments by default.

Gemfile.lock

@@ -33,6 +33,7 @@ GEM
     arel (3.0.0)
     awesome_print (0.4.0)
     builder (3.0.0)
+    bzip2-ruby (0.2.7)
     capybara (1.1.2)
       mime-types (>= 1.16)
       nokogiri (>= 1.3.3)
@@ -204,6 +205,7 @@ PLATFORMS
 
 DEPENDENCIES
   awesome_print
+  bzip2-ruby
   capybara
   carrierwave
   coffee-rails

app/assets/javascripts/player/asciicast.js.coffee

@@ -0,0 +1,4 @@
+class AsciiIo.Asciicast extends Backbone.Model
+
+  url: ->
+    "/asciicasts/#{@get('id')}.json"

app/assets/javascripts/player/movie.js.coffee

@@ -2,13 +2,20 @@ class AsciiIo.Movie
   MIN_DELAY: 0.01
   SPEED: 1.0
 
-  constructor: (@data, @timing) ->
+  constructor: (@model) ->
     @frameNo = 0
     @dataIndex = 0
     @currentTime = 0
     @processedFramesTime = 0
     _.extend(this, Backbone.Events)
 
+  isLoaded: ->
+    @model.get('escaped_stdout_data') != undefined
+
+  load: ->
+    @model.fetch
+      success: => @play()
+
   play: ->
     @nextFrame()
 
@@ -21,13 +28,22 @@ class AsciiIo.Movie
   seek: (percent) ->
     # TODO
 
+  timing: ->
+    @model.get('stdout_timing_data')
+
+  data: ->
+    unless @_data
+      @_data = eval "'" + @model.get('escaped_stdout_data') + "'"
+
+    @_data
+
   nextFrame: () ->
     # return if @currentData.length > 100
 
-    if frame = @timing[@frameNo++] # @frameNo += 1
+    if frame = @timing()[@frameNo++] # @frameNo += 1
       [delay, count] = frame
 
-      frameData = @data.slice(@dataIndex, @dataIndex + count)
+      frameData = @data().slice(@dataIndex, @dataIndex + count)
       @dataIndex += count
 
       if delay <= @MIN_DELAY

app/assets/javascripts/player/player_view.js.coffee

@@ -1,7 +1,9 @@
 class AsciiIo.PlayerView extends Backbone.View
 
   initialize: (options) ->
-    @movie = new AsciiIo.Movie(options.data, options.timing)
+    @movie = new AsciiIo.Movie(@model)
+    @movie.load()
+
     @terminalView = new AsciiIo.TerminalView(
       cols:  this.options.cols
       lines: this.options.lines
@@ -39,4 +41,5 @@ class AsciiIo.PlayerView extends Backbone.View
       @terminalView.stopCursorBlink()
 
   play: ->
-    @movie.play()
+    if @movie.isLoaded()
+      @movie.play()

app/controllers/asciicasts_controller.rb

@@ -1,4 +1,5 @@
 class AsciicastsController < ApplicationController
+  respond_to :html, :json
 
   def index
     @asciicasts = Asciicast.order("created_at DESC")
@@ -6,6 +7,7 @@ class AsciicastsController < ApplicationController
 
   def show
     @asciicast = Asciicast.find(params[:id])
+    respond_with @asciicast
   end
 
 end

app/helpers/asciicasts_helper.rb

@@ -1,31 +1,14 @@
 module AsciicastsHelper
 
-  def player_data(asciicast)
-    data = `bzip2 -d -c #{asciicast.stdout.path}`
-    time = `bzip2 -d -c #{asciicast.stdout_timing.path}`
-
-    data_hex_array = data.bytes.map { |b| '\x' + format('%02x', b) }
-    var_data = "'#{data_hex_array.join}'"
-
-    time_lines = time.lines.map do |line|
-      delay, n = line.split
-      "[#{delay.to_f}, #{n.to_i}]"
-    end
-    var_time = "[#{time_lines.join(',')}]"
-
-    <<EOS.html_safe
+  def player_script(asciicast)
+    return <<EOS.html_safe
 <script>
-  var data = #{var_data};
-  var time = #{j var_time};
-  var cols = #{asciicast.terminal_columns};
-  var lines = #{asciicast.terminal_lines};
   $(function() {
     window.player = new AsciiIo.PlayerView({
       el: $('.player'),
-      cols: cols,
-      lines: lines,
-      data: data,
-      timing: time
+      cols: #{asciicast.terminal_columns},
+      lines: #{asciicast.terminal_lines},
+      model: new AsciiIo.Asciicast({ id: #{asciicast.id} })
     });
 
     window.player.play();

app/models/asciicast.rb

@@ -20,4 +20,27 @@ class Asciicast < ActiveRecord::Base
     self.terminal_columns = data['term']['columns']
     self.terminal_type    = data['term']['type']
   end
+
+  def as_json(opts = {})
+    super :methods => [:escaped_stdout_data, :stdout_timing_data]
+  end
+
+  def escaped_stdout_data
+    if data = stdout.read
+      Bzip2.uncompress(data).bytes.map { |b| '\x' + format('%02x', b) }.join
+    else
+      nil
+    end
+  end
+
+  def stdout_timing_data
+    if data = stdout_timing.read
+      Bzip2.uncompress(data).lines.map do |line|
+        delay, n = line.split
+        [delay.to_f, n.to_i]
+      end
+    else
+      nil
+    end
+  end
 end

app/views/asciicasts/show.html.erb

@@ -13,4 +13,4 @@
   <p>But like anything else with Vim, there are always multiple ways of accomplishing the very same thing, so I make no guarantees that there aren’t simpler ways of getting this done — but I can say that this way gets the job done, and is pretty easy to get working on your own system.</p>
 </div>
 
-<%= player_data(@asciicast) %>
+<%= player_script(@asciicast) %>

config/application.rb

@@ -54,3 +54,5 @@ module AsciiIo
     config.assets.version = '1.0'
   end
 end
+
+ActiveRecord::Base.include_root_in_json = false