From fe49dcc963d315fc8ae024bb1d85645cb68db576 Mon Sep 17 00:00:00 2001
From: cbhakar <chandrabhakar@gmail.com>
Date: Fri, 8 Oct 2021 14:56:10 +0530
Subject: [PATCH 1/4] optimised boolean conditions

---
 pkg/manager/api_agent.go | 6 +-----
 pkg/manager/server.go    | 7 +------
 2 files changed, 2 insertions(+), 11 deletions(-)

diff --git a/pkg/manager/api_agent.go b/pkg/manager/api_agent.go
index 4ef7a9a..c218a4c 100644
--- a/pkg/manager/api_agent.go
+++ b/pkg/manager/api_agent.go
@@ -847,11 +847,7 @@ func upsertAgent(ctx *common.Context, tx *Tx, agent *Agents, ch *common.CustomHe
 }
 
 func byteToBool(b byte) bool {
-	if b == 0 {
-		return false
-	}
-
-	return true
+	return b != 0
 }
 
 func boolToByte(b bool) byte {
diff --git a/pkg/manager/server.go b/pkg/manager/server.go
index d2e7aeb..d45ee6a 100644
--- a/pkg/manager/server.go
+++ b/pkg/manager/server.go
@@ -722,12 +722,7 @@ func checkLock(tx *Tx, instanceID string, d time.Duration) bool {
 func expired(lockDate time.Time, d time.Duration) bool {
 	current := time.Now().UTC()
 	compare := lockDate.Add(d)
-
-	if current.After(compare) {
-		return true
-	}
-
-	return false
+	return current.After(compare)
 }
 
 func (manager *KlevrManager) encrypt(msg string) string {

From 8be6a469077fb7f233a4f186cbda84c0a5b81c24 Mon Sep 17 00:00:00 2001
From: cbhakar <chandrabhakar@gmail.com>
Date: Fri, 8 Oct 2021 15:00:39 +0530
Subject: [PATCH 2/4] removed unwanted for loops

---
 pkg/agent/handshake.go | 4 +---
 pkg/agent/scheduler.go | 5 ++---
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/pkg/agent/handshake.go b/pkg/agent/handshake.go
index 4216ea9..8872662 100644
--- a/pkg/agent/handshake.go
+++ b/pkg/agent/handshake.go
@@ -50,9 +50,7 @@ func (agent *KlevrAgent) handShake() *common.Primary {
 	agent.schedulerInterval = body.Me.CallCycle
 
 	if len(body.Agent.Nodes) > 0 {
-		for _, v := range body.Agent.Nodes {
-			agent.Agents = append(agent.Agents, v)
-		}
+		agent.Agents = append(agent.Agents, body.Agent.Nodes...)
 	}
 
 	return &body.Agent.Primary
diff --git a/pkg/agent/scheduler.go b/pkg/agent/scheduler.go
index 69c9f43..b25f3d0 100644
--- a/pkg/agent/scheduler.go
+++ b/pkg/agent/scheduler.go
@@ -103,9 +103,8 @@ func (agent *KlevrAgent) getRemoteUpdatedTasks() []common.KlevrTask {
 
 					logger.Debugf("tasks: %v", tasks)
 
-					for _, item := range tasks {
-						remoteTasks = append(remoteTasks, item)
-					}
+					remoteTasks = append(remoteTasks, tasks...)
+
 				} else {
 					logger.Debugf("getRemoteUpdatedTasks error: %v", resErr)
 				}

From 990a71c6ffd4dc8092a7b1b1a6442f48fa664d8f Mon Sep 17 00:00:00 2001
From: cbhakar <chandrabhakar@gmail.com>
Date: Fri, 8 Oct 2021 15:10:20 +0530
Subject: [PATCH 3/4] removed unused variables

---
 pkg/common/task_executor.go | 4 ++--
 pkg/manager/api_agent.go    | 2 +-
 pkg/manager/repository.go   | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/pkg/common/task_executor.go b/pkg/common/task_executor.go
index ffafc43..0fd6947 100644
--- a/pkg/common/task_executor.go
+++ b/pkg/common/task_executor.go
@@ -326,9 +326,9 @@ func (executor *taskExecutor) execute(tw *TaskWrapper) {
 			}(err)
 
 			if RESERVED == tw.recover.CommandType {
-				result, err = runReservedCommand(tw.Result, tw.KlevrTask, tw.recover)
+				result, _ = runReservedCommand(tw.Result, tw.KlevrTask, tw.recover)
 			} else if INLINE == tw.recover.CommandType {
-				result, err = runInlineCommand(tw.Result, tw.KlevrTask, tw.recover)
+				result, _ = runInlineCommand(tw.Result, tw.KlevrTask, tw.recover)
 			}
 
 			tw.Result = result
diff --git a/pkg/manager/api_agent.go b/pkg/manager/api_agent.go
index c218a4c..a026d15 100644
--- a/pkg/manager/api_agent.go
+++ b/pkg/manager/api_agent.go
@@ -367,7 +367,7 @@ func (api *agentAPI) receivePolling(w http.ResponseWriter, r *http.Request) {
 		}
 
 		// Credential 조회
-		nCredentials, cnt := tx.getCredentials(ch.ZoneID)
+		nCredentials, _ := tx.getCredentials(ch.ZoneID)
 
 		// 신규 task 할당
 		nTasks, cnt := tx.getTasksWithSteps(manager, ch.ZoneID, []string{string(common.WaitPolling), string(common.HandOver)})
diff --git a/pkg/manager/repository.go b/pkg/manager/repository.go
index f8db315..6478245 100644
--- a/pkg/manager/repository.go
+++ b/pkg/manager/repository.go
@@ -408,11 +408,11 @@ func (tx *Tx) updateTask(manager *KlevrManager, t *Tasks) {
 	if detail.Result != "" {
 		detail.Result = manager.encrypt(detail.Result)
 
-		cnt, err = tx.Where("TASK_ID = ?", t.Id).
+		_, err = tx.Where("TASK_ID = ?", t.Id).
 			Cols("CURRENT_STEP", "RESULT", "FAILED_STEP", "IS_FAILED_RECOVER").
 			Update(detail)
 	} else {
-		cnt, err = tx.Where("TASK_ID = ?", t.Id).
+		_, err = tx.Where("TASK_ID = ?", t.Id).
 			Cols("CURRENT_STEP", "FAILED_STEP", "IS_FAILED_RECOVER").
 			Update(detail)
 	}

From 2124e12b53ff226d087c040f908b5a594e9d858b Mon Sep 17 00:00:00 2001
From: cbhakar <chandrabhakar@gmail.com>
Date: Fri, 8 Oct 2021 15:51:56 +0530
Subject: [PATCH 4/4] suggested pattern should be followed to avoid confusion

---
 cmd/klevr-agent/main.go        |  8 ++---
 pkg/agent/agent.go             |  2 +-
 pkg/agent/scheduler_primary.go |  2 +-
 pkg/common/commands.go         |  2 +-
 pkg/common/encrypt.go          |  2 +-
 pkg/common/queue.go            | 63 ++++++++++++++++------------------
 pkg/manager/api.go             |  2 +-
 pkg/manager/api_agent.go       |  2 +-
 pkg/manager/api_console.go     |  6 ++--
 pkg/manager/api_inner.go       | 10 +++---
 pkg/manager/cache.go           | 10 ++++--
 pkg/manager/docs/docs.go       |  2 +-
 pkg/manager/repository.go      |  2 +-
 pkg/manager/server.go          | 12 +++----
 pkg/rabbitmq/rabbitmq.go       |  3 +-
 test/repository_test.go        |  3 +-
 16 files changed, 64 insertions(+), 67 deletions(-)

diff --git a/cmd/klevr-agent/main.go b/cmd/klevr-agent/main.go
index a15a3b5..49d940d 100644
--- a/cmd/klevr-agent/main.go
+++ b/cmd/klevr-agent/main.go
@@ -38,19 +38,19 @@ func main() {
 	flag.Parse() // Important for parsing
 
 	// Check the null data from CLI
-	if len(*apikey) == 0 {
+	if *apikey == "" {
 		logger.Error("Please insert an API Key")
 		os.Exit(0)
 	}
-	if len(*platform) == 0 {
+	if *platform == "" {
 		logger.Error("Please make sure the platform")
 		os.Exit(0)
 	}
-	if len(*zone) == 0 {
+	if *zone == "" {
 		logger.Error("Please insert zoneId")
 		os.Exit(0)
 	}
-	if len(*klevrAddr) == 0 {
+	if *klevrAddr == "" {
 		logger.Error("Please insert manager addr")
 		os.Exit(0)
 	}
diff --git a/pkg/agent/agent.go b/pkg/agent/agent.go
index d45f0df..c489889 100644
--- a/pkg/agent/agent.go
+++ b/pkg/agent/agent.go
@@ -116,7 +116,7 @@ func (agent *KlevrAgent) updateScheduler() {
 			interval = defaultSchedulerInterval
 		}
 		if oldSchedulerInterval != interval {
-			if agent.scheduler.IsRunning() == true {
+			if agent.scheduler.IsRunning() {
 				agent.scheduler.Clear()
 				if agent.checkPrimary(agent.Primary.IP) {
 					agent.scheduler.Every(int(interval)).Seconds().Do(agent.polling)
diff --git a/pkg/agent/scheduler_primary.go b/pkg/agent/scheduler_primary.go
index b71b3f9..3657b52 100644
--- a/pkg/agent/scheduler_primary.go
+++ b/pkg/agent/scheduler_primary.go
@@ -57,7 +57,7 @@ func (agent *KlevrAgent) assignmentTask(primaryAgentKey string, task []common.Kl
 }
 
 func (agent *KlevrAgent) polling() {
-	if agent.taskPollingPause == true {
+	if agent.taskPollingPause {
 		logger.Debug("Polling aborted because authentication failed.")
 		return
 	}
diff --git a/pkg/common/commands.go b/pkg/common/commands.go
index 54b2409..b519570 100644
--- a/pkg/common/commands.go
+++ b/pkg/common/commands.go
@@ -241,7 +241,7 @@ func collectAgentLog() Command {
 
 				cutData := make([]byte, baseSize)
 
-				copy(cutData[:], data[sIndex:eIndex])
+				copy(cutData, data[sIndex:eIndex])
 
 				data = cutData
 			}
diff --git a/pkg/common/encrypt.go b/pkg/common/encrypt.go
index 5b8fb97..6747ec5 100644
--- a/pkg/common/encrypt.go
+++ b/pkg/common/encrypt.go
@@ -144,7 +144,7 @@ func Decrypt(key string, crypt string) (decrypted string, err error) {
 	dec := make([]byte, len(b))
 	ecb.CryptBlocks(dec, b)
 	decrypt := getPKCS5Trimming(dec)
-	decrypt = decrypt[8:len(decrypt)]
+	decrypt = decrypt[8:]
 
 	b, err = encoder.DecodeString(string(decrypt))
 	if err != nil {
diff --git a/pkg/common/queue.go b/pkg/common/queue.go
index 892c786..3890165 100644
--- a/pkg/common/queue.go
+++ b/pkg/common/queue.go
@@ -54,43 +54,38 @@ func NewChannelQueue(chanBufSize uint32) *Queue {
 
 	// Queue 생성 시 큐에 삽입되는 데이터를 채널로 받아 처리하기 위한 listener go routine. Close()가 호출되면 종료된다.
 	go func() {
-		// alive가 false가 될 때까지 반복 처리
-		for q.alive {
-			// select로 buf 채널을 수신
-			select {
-			case newItem := <-q.buf:
-				// buf에 nil이 들어오면 queue가 종료된다. (Close() 를 통해 nil을 전달 받아 종료시킨다.)
-				if newItem != nil {
-					nq := &queueItem{
-						item: newItem,
-						next: nil,
-					}
-
-					if q.length == 0 {
-						// 빈 큐에 데이터가 삽입될 시 출력 채널과 데이터가 동기화 되어 go routine이 block 되므로 새로운 go routine에서 채널을 전송한다.
-						go func() {
-							q.current <- nq
-						}()
-					} else {
-						q.last.next = nq
-					}
-
-					q.last = nq
-					q.length++
-
-					if q.listener != nil {
-						q.listenerRunCount++
-
-						// 리스너 함수가 설정되고 호출 건수가 만족되면 리스너 함수를 호출한다.
-						if q.listenerRunCount >= q.listenerCallCount {
-							// 리스너 함수는 별도의 go routine으로 호출되므로 호출 시점의 누적 건수와 실행 시점의 누적 건수는 차이가 발생할 수 있다.
-							go q.listener(&Q)
-							q.listenerRunCount = 0
-						}
-					}
+		newItem := <-q.buf
+		// buf에 nil이 들어오면 queue가 종료된다. (Close() 를 통해 nil을 전달 받아 종료시킨다.)
+		if newItem != nil {
+			nq := &queueItem{
+				item: newItem,
+				next: nil,
+			}
+
+			if q.length == 0 {
+				// 빈 큐에 데이터가 삽입될 시 출력 채널과 데이터가 동기화 되어 go routine이 block 되므로 새로운 go routine에서 채널을 전송한다.
+				go func() {
+					q.current <- nq
+				}()
+			} else {
+				q.last.next = nq
+			}
+
+			q.last = nq
+			q.length++
+
+			if q.listener != nil {
+				q.listenerRunCount++
+
+				// 리스너 함수가 설정되고 호출 건수가 만족되면 리스너 함수를 호출한다.
+				if q.listenerRunCount >= q.listenerCallCount {
+					// 리스너 함수는 별도의 go routine으로 호출되므로 호출 시점의 누적 건수와 실행 시점의 누적 건수는 차이가 발생할 수 있다.
+					go q.listener(&Q)
+					q.listenerRunCount = 0
 				}
 			}
 		}
+
 	}()
 
 	return &Q
diff --git a/pkg/manager/api.go b/pkg/manager/api.go
index 00fdafb..d2a2371 100644
--- a/pkg/manager/api.go
+++ b/pkg/manager/api.go
@@ -98,7 +98,7 @@ func Init(ctx *common.Context) *API {
 	api.InitAgent(api.BaseRoutes.Agent)
 	api.InitInstall(api.BaseRoutes.Install)
 	api.InitInner(api.BaseRoutes.Inner)
-	if api.Manager.Config.Console.Usage == true {
+	if api.Manager.Config.Console.Usage {
 		api.InitConsole(api.BaseRoutes.Console)
 	}
 
diff --git a/pkg/manager/api_agent.go b/pkg/manager/api_agent.go
index a026d15..95bb710 100644
--- a/pkg/manager/api_agent.go
+++ b/pkg/manager/api_agent.go
@@ -323,7 +323,7 @@ func (api *agentAPI) receivePolling(w http.ResponseWriter, r *http.Request) {
 				arrAgent[i].FreeDisk = manager.encrypt(strconv.Itoa(a.FreeDisk))
 				arrAgent[i].IsActive = boolToByte(a.IsActive)
 
-				if a.IsActive == false {
+				if !a.IsActive {
 					inactiveAgentKeys = append(inactiveAgentKeys, a.AgentKey)
 					if tid, ok := CheckShutdownTask(a.AgentKey); ok {
 						agentKeys = append(agentKeys, a.AgentKey)
diff --git a/pkg/manager/api_console.go b/pkg/manager/api_console.go
index 8809586..1e178eb 100644
--- a/pkg/manager/api_console.go
+++ b/pkg/manager/api_console.go
@@ -153,7 +153,7 @@ func (api *ConsoleAPI) ChangePassword(w http.ResponseWriter, r *http.Request) {
 	}
 
 	pm := (*pms)[0]
-	if pm.Activated == true {
+	if pm.Activated {
 		decPassword, err := common.Decrypt(manager.Config.Server.EncryptionKey, pm.UserPassword)
 		if err != nil || pw != decPassword {
 			w.WriteHeader(http.StatusUnauthorized)
@@ -203,7 +203,7 @@ func (api *ConsoleAPI) Activated(w http.ResponseWriter, r *http.Request) {
 
 	pm := (*pms)[0]
 	var activatedStatus string
-	if pm.Activated == true {
+	if pm.Activated {
 		activatedStatus = "activated"
 	} else {
 		activatedStatus = "initialized"
@@ -251,7 +251,7 @@ func (api *ConsoleAPI) UnActivated(w http.ResponseWriter, r *http.Request) {
 	}
 
 	pm := (*pms)[0]
-	if pm.Activated == true {
+	if pm.Activated {
 		manager := ctx.Get(CtxServer).(*KlevrManager)
 		encPassword, err := common.Encrypt(manager.Config.Server.EncryptionKey, "admin")
 		if err != nil {
diff --git a/pkg/manager/api_inner.go b/pkg/manager/api_inner.go
index d8dc8ac..498887c 100644
--- a/pkg/manager/api_inner.go
+++ b/pkg/manager/api_inner.go
@@ -709,7 +709,7 @@ func (api *serversAPI) getTasks(w http.ResponseWriter, r *http.Request) {
 	logger.Debugf("%d", len(agentKeys))
 	logger.Debugf("%d", len(taskNames))
 
-	if groupIDs == nil || len(groupIDs) == 0 {
+	if len(groupIDs) == 0 {
 		common.WriteHTTPError(400, w, nil, "Query parameter groupID is required.")
 		return
 	}
@@ -1030,7 +1030,7 @@ func (api *serversAPI) deleteGroup(w http.ResponseWriter, r *http.Request) {
 func (api *serversAPI) deletegroup(ctx *common.Context, tx *Tx, id uint64) error {
 	tx.deletePrimaryAgent(id)
 	_, ok := tx.getPrimaryAgent(id)
-	if ok == true {
+	if ok {
 		return fmt.Errorf("It cannot remove the zone(primaryagent) of the zoneid: %d", id)
 	}
 
@@ -1224,13 +1224,13 @@ func TaskMatchingCredential(manager *KlevrManager, task Tasks, credential *[]Cre
 		return task
 	}
 
-	if len(task.TaskDetail.Parameter) == 0 {
+	if task.TaskDetail.Parameter == "" {
 		return task
 	}
 
 	r := regexp.MustCompile("{{2}[a-zA-Z0-9]*}{2}")
 	isMatch := r.MatchString(task.TaskDetail.Parameter)
-	if isMatch == false {
+	if !isMatch {
 		return task
 	}
 
@@ -1239,7 +1239,7 @@ func TaskMatchingCredential(manager *KlevrManager, task Tasks, credential *[]Cre
 		v := manager.decrypt(c.Value)
 
 		re := regexp.MustCompile(pattern)
-		task.TaskDetail.Parameter = fmt.Sprintf("%s", re.ReplaceAllString(task.TaskDetail.Parameter, v))
+		task.TaskDetail.Parameter =  re.ReplaceAllString(task.TaskDetail.Parameter, v)
 		logger.Debugf("Apply Credential : %s", task.TaskDetail.Parameter)
 	}
 
diff --git a/pkg/manager/cache.go b/pkg/manager/cache.go
index 5eb6ec2..fa49018 100644
--- a/pkg/manager/cache.go
+++ b/pkg/manager/cache.go
@@ -297,10 +297,14 @@ func (c *Cache) GetAgentsForInactive(ctx *common.Context, before time.Time) (int
 
 		for _, member := range members {
 			var buf Agents
-			json.Unmarshal([]byte(member), &buf)
+			err = json.Unmarshal([]byte(member), &buf)
+			if err != nil {
+				logger.Debug(err)
+				return 0, nil
+			}
 
-			if byteToBool(buf.IsActive) == true {
-				if res := buf.LastAccessTime.Before(before); res == true {
+			if byteToBool(buf.IsActive) {
+				if res := buf.LastAccessTime.Before(before); res {
 					inactivedAgents = append(inactivedAgents, buf)
 				}
 			} else {
diff --git a/pkg/manager/docs/docs.go b/pkg/manager/docs/docs.go
index 35b4a32..0cb0618 100644
--- a/pkg/manager/docs/docs.go
+++ b/pkg/manager/docs/docs.go
@@ -1790,7 +1790,7 @@ type s struct{}
 
 func (s *s) ReadDoc() string {
 	sInfo := SwaggerInfo
-	sInfo.Description = strings.Replace(sInfo.Description, "\n", "\\n", -1)
+	sInfo.Description = strings.ReplaceAll(sInfo.Description, "\n", "\\n")
 
 	t, err := template.New("swagger_info").Funcs(template.FuncMap{
 		"marshal": func(v interface{}) string {
diff --git a/pkg/manager/repository.go b/pkg/manager/repository.go
index 6478245..a1e68ba 100644
--- a/pkg/manager/repository.go
+++ b/pkg/manager/repository.go
@@ -791,7 +791,7 @@ func (tx *Tx) getCredentialByName(zoneID uint64, credentialName string) *Credent
 	exist := common.CheckGetQuery(tx.Where("CREDENTIALS.ZONE_ID = ?", zoneID).And("CREDENTIALS.KEY = ?", credentialName).Get(&credential))
 	logger.Debugf("Selected Credentials : exist[%v], id[%d], key[%s]", exist, credential.Id, credential.Key)
 
-	if exist == false {
+	if !exist {
 		return nil
 	}
 
diff --git a/pkg/manager/server.go b/pkg/manager/server.go
index d45ee6a..9583ff1 100644
--- a/pkg/manager/server.go
+++ b/pkg/manager/server.go
@@ -143,7 +143,7 @@ func (manager *KlevrManager) Run() error {
 	ctx.Put(CtxDbConn, db)
 	ctx.Put(CtxPrimary, &sync.Mutex{})
 
-	if manager.Config.DB.Cache == true {
+	if manager.Config.DB.Cache {
 		ctx.Put(CtxCacheLock, &sync.Mutex{})
 	}
 
@@ -634,16 +634,16 @@ func (manager *KlevrManager) updateAgentStatus(ctx *common.Context, cycle int) {
 					cnt, agents := txManager.GetAgentsForInactive(ctx, tx, before)
 
 					if cnt > 0 {
-						len := len(*agents)
-						inactiveIDs := make([]uint64, len)
-						inactiveAgentKeys := make([]string, len)
+						agentLen := len(*agents)
+						inactiveIDs := make([]uint64, agentLen)
+						inactiveAgentKeys := make([]string, agentLen)
 						forceShutdownAgentKeys := make([]string, 0)
 						taskIDs := make([]uint64, 0)
 
-						var events = make([]KlevrEvent, len)
+						var events = make([]KlevrEvent, agentLen)
 						var eventTime = &common.JSONTime{Time: time.Now().UTC()}
 
-						for i := 0; i < len; i++ {
+						for i := 0; i < agentLen; i++ {
 							agent := (*agents)[i]
 
 							inactiveIDs[i] = agent.Id
diff --git a/pkg/rabbitmq/rabbitmq.go b/pkg/rabbitmq/rabbitmq.go
index afba9df..afb2131 100644
--- a/pkg/rabbitmq/rabbitmq.go
+++ b/pkg/rabbitmq/rabbitmq.go
@@ -126,9 +126,8 @@ func DialCluster(urls []string) (*Connection, error) {
 			if i < count-1 {
 				err = nil
 				continue
-			} else {
-				return nil, errors.Wrap(err, "all connection failed.")
 			}
+			return nil, errors.Wrap(err, "all connection failed.")
 		}
 
 		connection = &Connection{
diff --git a/test/repository_test.go b/test/repository_test.go
index e38a103..5f035b6 100644
--- a/test/repository_test.go
+++ b/test/repository_test.go
@@ -22,8 +22,7 @@ func TestToTasks(t *testing.T) {
 		TaskDetail: &manager.TaskDetail{TaskId: 2},
 	})
 
-	var nrts *[]manager.RetriveTask
-	nrts = &rts
+	nrts := &rts
 
 	var tasks = make([]manager.Tasks, 0)
 	var tasks2 *[]manager.Tasks