FEATURE: add a simple queue Scheduler::Defer.later {}

For quick jobs that do not need to be sent to sidekiq,
runs inline in a single thread but does not block

lib/auth/default_current_user_provider.rb

@@ -33,9 +33,12 @@ class Auth::DefaultCurrentUserProvider
 
     if current_user
 
-      Jobs.enqueue(:update_user_info,
+      u = current_user
-                    user_id: current_user.id,
+      Scheduler::Defer.later do
-                    ip: request.ip)
+        u.update_last_seen!
+        u.update_ip_address!(request.ip)
+      end
+
     end
 
     # possible we have an api call, impersonate

lib/scheduler/defer.rb

@@ -0,0 +1,48 @@
+module Scheduler
+  module Deferrable
+    def initialize
+      @async = Rails.env != "test"
+      @queue = Queue.new
+      @thread = Thread.new {
+        while true
+          do_work
+        end
+      }
+    end
+
+    # for test
+    def async=(val)
+      @async = val
+    end
+
+    def later(&blk)
+      if @async
+        @queue << [RailsMultisite::ConnectionManagement.current_db, blk]
+      else
+        blk.call
+      end
+    end
+
+    def stop!
+      @thread.kill
+    end
+
+    private
+
+    def do_work
+      db, job = @queue.deq
+      RailsMultisite::ConnectionManagement.establish_connection(db: db)
+      job.call
+    rescue => ex
+      Discourse.handle_exception(ex)
+    ensure
+      ActiveRecord::Base.connection_handler.clear_active_connections!
+    end
+
+  end
+
+  class Defer
+    extend Deferrable
+    initialize
+  end
+end

lib/scheduler/scheduler.rb

@@ -4,3 +4,4 @@ end
 require_dependency 'scheduler/schedule'
 require_dependency 'scheduler/schedule_info'
 require_dependency 'scheduler/manager'
+require_dependency 'scheduler/defer'

spec/components/scheduler/defer_spec.rb

@@ -0,0 +1,40 @@
+# encoding: utf-8
+require 'spec_helper'
+require 'scheduler/scheduler'
+
+describe Scheduler::Defer do
+  class DeferInstance
+    include Scheduler::Deferrable
+  end
+
+  def wait_for(timeout, &blk)
+    till = Time.now + (timeout.to_f / 1000)
+    while Time.now < till && !blk.call
+      sleep 0.001
+    end
+  end
+
+  before do
+    @defer = DeferInstance.new
+    @defer.async = true
+  end
+
+  after do
+    @defer.stop!
+  end
+
+  it "can queue jobs properly" do
+    s = nil
+
+    @defer.later do
+      s = "good"
+    end
+
+    wait_for(10) do
+      s == "good"
+    end
+
+    s.should == "good"
+  end
+
+end