Live timelines using ActionCable

Gemfile

@@ -35,7 +35,6 @@ gem 'onebox'
 gem 'simple_form'
 gem 'will_paginate'
 gem 'rack-attack'
-gem 'turbolinks'
 gem 'sidekiq'
 gem 'sinatra', require: nil, github: 'sinatra'
 
@@ -66,5 +65,5 @@ group :production do
 end
 
 group :development, :production do
-  gem 'rack-mini-profiler', require: false
+  gem 'rack-mini-profiler'
 end

Gemfile.lock

@@ -321,9 +321,6 @@ GEM
     thread_safe (0.3.5)
     tilt (2.0.5)
     tool (0.2.3)
-    turbolinks (5.0.1)
-      turbolinks-source (~> 5)
-    turbolinks-source (5.0.0)
     tzinfo (1.2.2)
       thread_safe (~> 0.1)
     uglifier (3.0.1)
@@ -394,7 +391,6 @@ DEPENDENCIES
   simplecov
   sinatra!
   therubyracer
-  turbolinks
   uglifier (>= 1.3.0)
   webmock
   will_paginate

app/assets/javascripts/api/accounts.coffee

-# Place all the behaviors and hooks related to the matching controller here.
-# All this logic will automatically be available in application.js.
-# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/javascripts/api/accounts/lookup.coffee

-# Place all the behaviors and hooks related to the matching controller here.
-# All this logic will automatically be available in application.js.
-# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/javascripts/api/follows.coffee

-# Place all the behaviors and hooks related to the matching controller here.
-# All this logic will automatically be available in application.js.
-# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/javascripts/api/statuses.coffee

-# Place all the behaviors and hooks related to the matching controller here.
-# All this logic will automatically be available in application.js.
-# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/javascripts/application.js

@@ -12,5 +12,4 @@
 //
 //= require jquery
 //= require jquery_ujs
-//= require turbolinks
 //= require_tree .

app/assets/javascripts/cable.js

+// Action Cable provides the framework to deal with WebSockets in Rails.
+// You can generate new channels where WebSocket features live using the rails generate channel command.
+//
+//= require action_cable
+//= require_self
+//= require_tree ./channels
+
+(function() {
+  this.App || (this.App = {});
+
+  App.cable = ActionCable.createConsumer();
+
+}).call(this);

app/assets/javascripts/channels/timeline.js

+App.timeline = App.cable.subscriptions.create("TimelineChannel", {
+  connected: function() {
+    console.log('Connected');
+  },
+
+  disconnected: function() {
+    console.log('Disconnected');
+  },
+
+  received: function(data) {
+    console.log(JSON.parse(data.message));
+  }
+});

app/assets/javascripts/oauth/applications.coffee

-# Place all the behaviors and hooks related to the matching controller here.
-# All this logic will automatically be available in application.js.
-# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/javascripts/profiler.coffee

-$ ->
-  $(document).on 'turbolinks:load', ->
-    unless typeof window.MiniProfiler == 'undefined'
-      window.MiniProfiler.init()
-      window.MiniProfiler.pageTransition()

app/assets/javascripts/settings.coffee

-# Place all the behaviors and hooks related to the matching controller here.
-# All this logic will automatically be available in application.js.
-# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/javascripts/statuses.coffee

-# Place all the behaviors and hooks related to the matching controller here.
-# All this logic will automatically be available in application.js.
-# You can use CoffeeScript in this file: http://coffeescript.org/

app/channels/application_cable/channel.rb

+# Be sure to restart your server when you modify this file. Action Cable runs in a loop that does not support auto reloading.
+module ApplicationCable
+  class Channel < ActionCable::Channel::Base
+  end
+end

app/channels/application_cable/connection.rb

+# Be sure to restart your server when you modify this file. Action Cable runs in a loop that does not support auto reloading.
+module ApplicationCable
+  class Connection < ActionCable::Connection::Base
+    identified_by :current_user
+
+    def connect
+      self.current_user = find_verified_user
+    end
+
+    protected
+
+    def find_verified_user
+      if verified_user = env['warden'].user
+        verified_user
+      else
+        reject_unauthorized_connection
+      end
+    end
+  end
+end

app/channels/timeline_channel.rb

+# Be sure to restart your server when you modify this file. Action Cable runs in a loop that does not support auto reloading.
+class TimelineChannel < ApplicationCable::Channel
+  def subscribed
+    stream_from "timeline:#{current_user.id}"
+  end
+
+  def unsubscribed
+    # Any cleanup needed when channel is unsubscribed
+  end
+end

app/controllers/application_controller.rb

@@ -5,7 +5,7 @@ class ApplicationController < ActionController::Base
 
   # Profiling
   before_action do
-    if current_user && current_user.admin?
+    if (current_user && current_user.admin?) || Rails.env == 'development'
       Rack::MiniProfiler.authorize_request
     end
   end

app/services/fan_out_on_write_service.rb

@@ -10,13 +10,13 @@ class FanOutOnWriteService < BaseService
   private
 
   def deliver_to_self(status)
-    push(:home, status.account.id, status)
+    push(:home, status.account, status)
   end
 
   def deliver_to_followers(status)
     status.account.followers.each do |follower|
       next if !follower.local? || FeedManager.filter_status?(status, follower)
-      push(:home, follower.id, status)
+      push(:home, follower, status)
     end
   end
 
@@ -24,23 +24,38 @@ class FanOutOnWriteService < BaseService
     status.mentions.each do |mention|
       mentioned_account = mention.account
       next unless mentioned_account.local?
-      push(:mentions, mentioned_account.id, status)
+      push(:mentions, mentioned_account, status)
     end
   end
 
-  def push(type, receiver_id, status)
-    redis.zadd(FeedManager.key(type, receiver_id), status.id, status.id)
-    trim(type, receiver_id)
+  def push(type, receiver, status)
+    redis.zadd(FeedManager.key(type, receiver.id), status.id, status.id)
+    trim(type, receiver)
+    ActionCable.server.broadcast("timeline:#{receiver.id}", message: inline_render(receiver, status))
   end
 
-  def trim(type, receiver_id)
-    return unless redis.zcard(FeedManager.key(type, receiver_id)) > FeedManager::MAX_ITEMS
+  def trim(type, receiver)
+    return unless redis.zcard(FeedManager.key(type, receiver.id)) > FeedManager::MAX_ITEMS
 
-    last = redis.zrevrange(FeedManager.key(type, receiver_id), FeedManager::MAX_ITEMS - 1, FeedManager::MAX_ITEMS - 1)
-    redis.zremrangebyscore(FeedManager.key(type, receiver_id), '-inf', "(#{last.last}")
+    last = redis.zrevrange(FeedManager.key(type, receiver.id), FeedManager::MAX_ITEMS - 1, FeedManager::MAX_ITEMS - 1)
+    redis.zremrangebyscore(FeedManager.key(type, receiver.id), '-inf', "(#{last.last}")
   end
 
   def redis
     $redis
   end
+
+  def inline_render(receiver, status)
+    rabl_scope = Class.new(BaseService) do
+      def initialize(account)
+        @account = account
+      end
+
+      def current_user
+        @account.user
+      end
+    end
+
+    Rabl::Renderer.new('api/statuses/show', status,  view_path: 'app/views', format: :json, scope: rabl_scope.new(receiver)).render
+  end
 end

app/services/precompute_feed_service.rb

@@ -8,7 +8,7 @@ class PrecomputeFeedService < BaseService
 
     Status.send("as_#{type}_timeline", account).order('created_at desc').limit(FeedManager::MAX_ITEMS).each do |status|
       next if type == :home && FeedManager.filter_status?(status, account)
-      redis.zadd(FeedManager.key(type, receiver_id), status.id, status.id)
+      redis.zadd(FeedManager.key(type, account.id), status.id, status.id)
       instant_return << status unless instant_return.size > limit
     end
 

config/cable.yml

 development:
-  adapter: async
+  adapter: redis
+  url: redis://localhost:6379/1
 
 test:
   adapter: async