FEATURE: per host regular jobs

These are jobs that will run on every host that is running discourse.

If you have multiple hosts running the same site you get independent
schedules

spec/components/scheduler/manager_spec.rb

@@ -33,6 +33,25 @@ describe Scheduler::Manager do
         sleep 1000
       end
     end
+
+    class PerHostJob
+      extend ::Scheduler::Schedule
+
+      per_host
+      every 10.minutes
+
+      def self.runs=(val)
+        @runs = val
+      end
+
+      def self.runs
+        @runs ||= 0
+      end
+
+      def perform
+        self.class.runs += 1
+      end
+    end
   end
 
   let(:manager) { Scheduler::Manager.new(DiscourseRedis.new) }
@@ -42,12 +61,43 @@ describe Scheduler::Manager do
     $redis.del manager.class.queue_key
     manager.remove(Testing::RandomJob)
     manager.remove(Testing::SuperLongJob)
+    manager.remove(Testing::PerHostJob)
   end
 
   after do
     manager.stop!
     manager.remove(Testing::RandomJob)
     manager.remove(Testing::SuperLongJob)
+    manager.remove(Testing::PerHostJob)
+  end
+
+  describe 'per host jobs' do
+    it "correctly schedules on multiple hosts" do
+      Testing::PerHostJob.runs = 0
+
+      hosts = ['a','b','c']
+
+      hosts.map do |host|
+
+        manager = Scheduler::Manager.new(DiscourseRedis.new, hostname: host)
+        manager.ensure_schedule!(Testing::PerHostJob)
+
+        info = manager.schedule_info(Testing::PerHostJob)
+        info.next_run = Time.now.to_i - 1
+        info.write!
+
+        manager
+
+      end.each do |manager|
+
+        manager.blocking_tick
+        manager.stop!
+
+      end
+
+      expect(Testing::PerHostJob.runs).to eq(3)
+
+    end
   end
 
   describe '#sync' do
@@ -63,7 +113,6 @@ describe Scheduler::Manager do
       $redis.zadd Scheduler::Manager.queue_key, Time.now.to_i - 1000, "BLABLA"
       manager.tick
       expect($redis.zcard(Scheduler::Manager.queue_key)).to eq(0)
-
     end
 
     it 'should recover from crashed manager' do