Add delayed_jobs process.

Procfile

@@ -1,2 +1,3 @@
-web: bundle exec unicorn -p $PORT -c ./config/unicorn.rb
-imap_client: rake imap:client
+web:         bundle exec unicorn -p $PORT -c ./config/unicorn.rb
+worker:      env QUEUE=worker bundle exec rake jobs:work
+imap_client: bundle exec rake imap:client

bin/delayed_job

@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+
+require File.expand_path(File.join(File.dirname(__FILE__), '..', 'config', 'environment'))
+require 'delayed/command'
+Delayed::Command.new(ARGV).daemonize

db/migrate/20141207200312_create_delayed_jobs.rb

@@ -0,0 +1,22 @@
+class CreateDelayedJobs < ActiveRecord::Migration
+  def self.up
+    create_table :delayed_jobs, :force => true do |table|
+      table.integer :priority, :default => 0, :null => false # Allows some jobs to jump to the front of the queue
+      table.integer :attempts, :default => 0, :null => false # Provides for retries, but still fail eventually.
+      table.text :handler, :null => false                    # YAML-encoded string of the object that will do work
+      table.text :last_error                                 # reason for last failure (See Note below)
+      table.datetime :run_at                                 # When to run. Could be Time.zone.now for immediately, or sometime in the future.
+      table.datetime :locked_at                              # Set when a client is working on this object
+      table.datetime :failed_at                              # Set when all retries have failed (actually, by default, the record is deleted instead)
+      table.string :locked_by                                # Who is working on this object (if locked)
+      table.string :queue                                    # The name of the queue this job is in
+      table.timestamps
+    end
+
+    add_index :delayed_jobs, [:priority, :run_at], :name => 'delayed_jobs_priority'
+  end
+
+  def self.down
+    drop_table :delayed_jobs
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20141207191800) do
+ActiveRecord::Schema.define(version: 20141207200312) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -50,6 +50,22 @@
   add_index "admin_users", ["email"], name: "index_admin_users_on_email", unique: true, using: :btree
   add_index "admin_users", ["reset_password_token"], name: "index_admin_users_on_reset_password_token", unique: true, using: :btree
 
+  create_table "delayed_jobs", force: true do |t|
+    t.integer  "priority",   default: 0, null: false
+    t.integer  "attempts",   default: 0, null: false
+    t.text     "handler",                null: false
+    t.text     "last_error"
+    t.datetime "run_at"
+    t.datetime "locked_at"
+    t.datetime "failed_at"
+    t.string   "locked_by"
+    t.string   "queue"
+    t.datetime "created_at"
+    t.datetime "updated_at"
+  end
+
+  add_index "delayed_jobs", ["priority", "run_at"], name: "delayed_jobs_priority", using: :btree
+
   create_table "imap_daemon_heartbeats", force: true do |t|
     t.string   "tag"
     t.datetime "created_at"