1. separate timer in timer queue processor into dedicated file, add UT (

cadence-workflow#602)

* separate timer in timer queue processor into dedicated file, add UT
* increase history cache size from 256 to 512, note, this value was previously 1024

service/history/service.go

@@ -78,7 +78,7 @@ func NewConfig(dc *dynamicconfig.Collection, numberOfShards int) *Config {
 	return &Config{
 		NumberOfShards:                              numberOfShards,
 		HistoryCacheInitialSize:                     128,
-		HistoryCacheMaxSize:                         256,
+		HistoryCacheMaxSize:                         512,
 		HistoryCacheTTL:                             time.Hour,
 		RangeSizeBits:                               20, // 20 bits for sequencer, 2^20 sequence number for any range
 		AcquireShardInterval:                        time.Minute,

service/history/timerGate.go

@@ -0,0 +1,122 @@
+// Copyright (c) 2017 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package history
+
+import (
+	"sync"
+	"time"
+)
+
+type (
+	// TimerGate interface
+	TimerGate interface {
+		// FireChan return the channel which will be fired when time is up
+		FireChan() <-chan struct{}
+		// FireAfter check will the timer get fired after a certain time
+		FireAfter(now time.Time) bool
+		// Update update the timer gate, return true if update is a success
+		// success means timer is idle or timer is set with a sooner time to fire
+		Update(nextTime time.Time) bool
+		// Close shutdown the timer
+		Close()
+	}
+
+	// TimerGateImpl is an timer implementation,
+	// which basically is an wrrapper of golang's timer and
+	// additional feature
+	TimerGateImpl struct {
+		// the channel which will be used to proxy the fired timer
+		fireChan  chan struct{}
+		closeChan chan struct{}
+
+		// lock for timer and next wake up time
+		sync.Mutex
+		// the actual timer which will fire
+		timer *time.Timer
+		// variable indicating when the above timer will fire
+		nextWakeupTime time.Time
+	}
+)
+
+// NewTimerGate create a new timer gate instance
+func NewTimerGate() TimerGate {
+	timer := &TimerGateImpl{
+		timer:          time.NewTimer(0),
+		nextWakeupTime: time.Time{},
+		fireChan:       make(chan struct{}),
+		closeChan:      make(chan struct{}),
+	}
+
+	go func() {
+		defer close(timer.fireChan)
+		defer timer.timer.Stop()
+	loop:
+		for {
+			select {
+			case <-timer.timer.C:
+				// re-transmit on gateC
+				timer.fireChan <- struct{}{}
+
+			case <-timer.closeChan:
+				// closed; cleanup and quit
+				break loop
+			}
+		}
+	}()
+
+	return timer
+}
+
+// FireChan return the channel which will be fired when time is up
+func (timerGate *TimerGateImpl) FireChan() <-chan struct{} {
+	return timerGate.fireChan
+}
+
+// FireAfter check will the timer get fired after a certain time
+func (timerGate *TimerGateImpl) FireAfter(now time.Time) bool {
+	return timerGate.nextWakeupTime.After(now)
+}
+
+// Update update the timer gate, return true if update is a success
+// success means timer is idle or timer is set with a sooner time to fire
+func (timerGate *TimerGateImpl) Update(nextTime time.Time) bool {
+	now := time.Now()
+
+	timerGate.Lock()
+	defer timerGate.Unlock()
+	if !timerGate.FireAfter(now) || timerGate.nextWakeupTime.After(nextTime) {
+		// if timer will not fire or next wake time is after the "next"
+		// then we need to update the timer to fire
+		timerGate.nextWakeupTime = nextTime
+		// reset timer to fire when the next message should be made 'visible'
+		timerGate.timer.Reset(nextTime.Sub(now))
+
+		// Notifies caller that next notification is reset to fire at passed in 'next' visibility time
+		return true
+	}
+
+	return false
+}
+
+// Close shutdown the timer
+func (timerGate *TimerGateImpl) Close() {
+	close(timerGate.closeChan)
+}

service/history/timerGate_test.go

@@ -0,0 +1,114 @@
+// Copyright (c) 2017 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package history
+
+import (
+	"os"
+	"testing"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/suite"
+)
+
+type (
+	timerSuite struct {
+		suite.Suite
+		timerGate TimerGate
+	}
+)
+
+func TestTimerSuite(t *testing.T) {
+	s := new(timerSuite)
+	suite.Run(t, s)
+}
+
+func (s *timerSuite) SetupSuite() {
+	if testing.Verbose() {
+		log.SetOutput(os.Stdout)
+	}
+
+}
+
+func (s *timerSuite) TearDownSuite() {
+
+}
+
+func (s *timerSuite) SetupTest() {
+	s.timerGate = NewTimerGate()
+}
+
+func (s *timerSuite) TearDownTest() {
+	s.timerGate.Close()
+}
+
+func (s *timerSuite) TestTimerFire() {
+	now := time.Now()
+	timerDelay := now.Add(1 * time.Second)
+	deadlineDelay := now.Add(2 * time.Second)
+	s.timerGate.Update(timerDelay)
+
+	select {
+	case <-s.timerGate.FireChan():
+	case <-time.NewTimer(deadlineDelay.Sub(now)).C:
+		s.Fail("timer should fire before test deadline")
+	}
+}
+
+func (s *timerSuite) TestTimerFireAfterUpdate_Updated() {
+	now := time.Now()
+	timerDelay := now.Add(5 * time.Second)
+	updatedTimerDelay := now.Add(1 * time.Second)
+	deadlineDelay := now.Add(3 * time.Second)
+	s.timerGate.Update(timerDelay)
+	s.True(s.timerGate.Update(updatedTimerDelay))
+
+	select {
+	case <-s.timerGate.FireChan():
+	case <-time.NewTimer(deadlineDelay.Sub(now)).C:
+		s.Fail("timer should fire before test deadline")
+	}
+}
+
+func (s *timerSuite) TestTimerFireAfterUpdate_NotUpdated() {
+	now := time.Now()
+	timerDelay := now.Add(1 * time.Second)
+	updatedTimerDelay := now.Add(3 * time.Second)
+	deadlineDelay := now.Add(2 * time.Second)
+	s.timerGate.Update(timerDelay)
+	s.False(s.timerGate.Update(updatedTimerDelay))
+
+	select {
+	case <-s.timerGate.FireChan():
+	case <-time.NewTimer(deadlineDelay.Sub(now)).C:
+		s.Fail("timer should fire before test deadline")
+	}
+}
+
+func (s *timerSuite) TestTimerWillFire() {
+	now := time.Now()
+	timerDelay := now.Add(2 * time.Second)
+	timeBeforeTimer := now.Add(1 * time.Second)
+	timeAfterTimer := now.Add(3 * time.Second)
+	s.timerGate.Update(timerDelay)
+	s.True(s.timerGate.FireAfter(timeBeforeTimer))
+	s.False(s.timerGate.FireAfter(timeAfterTimer))
+}