title: How can I get ActiveJob to enqueue jobs in Sidekiq on Heroku when called from the app (not the console)?
body: <p>I'm running Rails 4.2 on Heroku (cedar), Ruby 2.1.6</p>
  
  <p>I've got Sidekiq running locally on Redis with Foreman, and in my app I call Rails' new ActiveJob deliver_later methods like this, inside <code>application_helper.rb</code>:</p>
  
  <pre><code>assigning_user = User.find(object.created_by)
  completing_user = User.find(object.completed_by)
  if NotificationMailer.assigned_user_completed_todo(object, completing_user, assigning_user).deliver_later
    nn.email_status = "sent"
  end
  </code></pre>
  
  <p>Locally, this works just as intended. Mails show up in the 'mailers' queue and then are processed and delivered using sendgrid. </p>
  
  <p>On <code>heroku run rails console</code> I can trigger it manually, and it works just fine:</p>
  
  <pre><code>Loading production environment (Rails 4.2.1)
  irb(main):001:0&gt; a = Account.first
  Account Load (1.5ms)  SELECT  "accounts".* FROM "accounts"  ORDER BY     "accounts"."id" ASC LIMIT 1
  =&gt; #&lt;Account id: 1, name: "The Prestons", stripe_customer_id: nil, active_until: "2015-06-27 14:50:43", plan: nil, created_at: "2015-04-27 14:50:43", updated_at: "2015-04-27 14:50:43"&gt;
  irb(main):002:0&gt; NotificationMailer.new_account_created(a).deliver_later
  Enqueued ActionMailer::DeliveryJob (Job ID: 7c0ddf9c-6892-4aa9-823e-9954b2a4e642) to Sidekiq(mailers) with arguments: "NotificationMailer", "new_account_created", "deliver_now", gid://raisin/Account/1
  =&gt; #&lt;ActionMailer::DeliveryJob:0x007f4d9ed9da58 @arguments=["NotificationMailer", "new_account_created", "deliver_now", #&lt;Account id: 1, name: "The Prestons", stripe_customer_id: nil, active_until: "2015-06-27 14:50:43", plan: nil, created_at: "2015-04-27 14:50:43", updated_at: "2015-04-27 14:50:43"&gt;], @job_id="7c0ddf9c-6892-4aa9-823e-9954b2a4e642", @queue_name="mailers"&gt;
  </code></pre>
  
  <p>but if I simply complete actions in my app, the way I would as a user, nothing is ever delivered to the queue... I am totally out of ideas. I am running a worker process. I am connected to the redis cloud server. I can see the sidekiq web dashboard. </p>
  
  <p>What am I not setting? Happy to provide other logs/info, but not sure what else to provide. </p>
  
  <p>My console simply reports the action:</p>
  
  <pre><code>2015-05-14T09:14:37.674095+00:00 heroku[router]: at=info method=POST path="/accounts/1/projects/15/lists/33/items/112" host=www.myapp.com request_id=516db810-8a2c-4fd0-af89-29a59783b0a8 fwd="76.104.193.78" dyno=web.1 connect=1ms service=111ms status=200 bytes=2039
  </code></pre>