add golangci lint and fix based on lint result

.github/workflows/golangci-lint.yml

@@ -0,0 +1,34 @@
+name: CI Lint
+
+on:
+  pull_request:
+    branches:
+      - main
+    paths:
+      - "**/*.go"
+      - ".github/workflows/golangci.lint.yml"
+
+env:
+  GO_VERSION: "1.20"
+
+jobs:
+
+  analysis:
+    runs-on: ubuntu-latest
+    steps:
+
+    - name: Set up Go
+      uses: actions/setup-go@v4
+      with:
+        go-version: ${{ env.GO_VERSION }}
+
+    - name: Check out code into the Go module directory
+      uses: actions/checkout@v3
+
+    - name: golangci-lint
+      uses: golangci/golangci-lint-action@v3
+      with:
+        version: v1.54
+        # no errcheck, and no check for deprecated code.
+        # since some deprecated code is used in the project and no perfect replacement is available yet.
+        args: --timeout=30m --disable=errcheck --exclude=SA1019

channel/channel.go

@@ -129,7 +129,7 @@ func (c *Channel) WatchEvent(wg *sync.WaitGroup) {
 	defer wg.Done()
 
 	// check if the channel is watching
-	if atomic.CompareAndSwapInt32(&(c.isWatch), 0, 1) == false {
+	if !atomic.CompareAndSwapInt32(&(c.isWatch), 0, 1) {
 		log.Warnf("[%s/ %s]: Channel is already watching!", kind, c.Name)
 		return
 	}
@@ -168,7 +168,7 @@ func (c *Channel) WatchEvent(wg *sync.WaitGroup) {
 
 			// if the status is DOWN, check the notification strategy
 			if result.Status == probe.StatusDown {
-				if result.Stat.NotificationStrategyData.NeedToSendNotification() == false {
+				if !result.Stat.NotificationStrategyData.NeedToSendNotification() {
 					log.Debugf("[%s / %s]: %s (%s) - Don't meet the notification condition [max=%d, notified=%d, failed=%d, next=%d], no notification.",
 						kind, c.Name, result.Name, result.Endpoint, nsd.MaxTimes, nsd.Notified, nsd.Failed, nsd.Next)
 					continue
@@ -184,7 +184,7 @@ func (c *Channel) WatchEvent(wg *sync.WaitGroup) {
 			}
 
 			for _, n := range c.Notifiers {
-				if IsDryNotify() == true {
+				if IsDryNotify() {
 					n.DryNotify(result)
 				} else {
 					go n.Notify(result)

conf/conf_test.go

@@ -175,16 +175,6 @@ func checkHTTPProbe(t *testing.T, probe httpProbe.HTTP) {
 	}
 }
 
-const confTCP = `
-tcp:
-  - name: Example SSH
-    host: example.com:22
-    timeout: 10s
-    interval: 2m
-  - name: Example HTTP
-    host: example.com:80
-`
-
 func checkTCPProbe(t *testing.T, probe tcp.TCP) {
 	switch probe.ProbeName {
 	case "Example SSH":
@@ -198,32 +188,6 @@ func checkTCPProbe(t *testing.T, probe tcp.TCP) {
 	}
 }
 
-const confShell = `
-shell:
-  - name: Google Service
-    cmd: "./resources/scripts/probe/proxy.curl.sh"
-    args:
-      - "socks5://127.0.0.1:1085"
-      - "www.google.com"
-    timeout: 20s
-    interval: 1m
-    channels:
-        - "telegram#Dev"
-  - name: Redis (Local)
-    cmd: "redis-cli"
-    args:
-      - "-h"
-      - "127.0.0.1"
-      - "-p"
-      - 6379
-      - "ping"
-    env:
-      - "REDISCLI_AUTH=abc123"
-    contain: "PONG"
-	channels:
-        - "slack"
-`
-
 func checkShellProbe(t *testing.T, probe shell.Shell) {
 	switch probe.ProbeName {
 	case "Google Service":

conf/log.go

@@ -122,7 +122,7 @@ func (l *Log) Open() {
 		return
 	}
 	// using lumberjack if self rotate
-	if l.SelfRotate == true {
+	if l.SelfRotate {
 		log.Debugf("[Log] Self Rotate log file %s", l.File)
 		l.IsStdout = false
 		l.Writer = &lumberjack.Logger{
@@ -167,7 +167,7 @@ func (l *Log) GetWriter() io.Writer {
 
 // Rotate rotate the log file
 func (l *Log) Rotate() {
-	if l.Writer == nil || l.IsStdout == true {
+	if l.Writer == nil || l.IsStdout {
 		return
 	}
 	if lumberjackLogger, ok := l.Writer.(*lumberjack.Logger); ok {

daemon/daemon_test.go

@@ -100,12 +100,12 @@ func TestPIDFileFailed(t *testing.T) {
 	assert.NotNil(t, err)
 
 	file = "./"
-	conf, err = NewPIDFile(file)
+	NewPIDFile(file)
 	assert.FileExists(t, global.DefaultPIDFile)
 	os.RemoveAll(global.DefaultPIDFile)
 
 	file = "dir/easedprobe.pid"
-	conf, err = NewPIDFile(file)
+	conf, _ = NewPIDFile(file)
 	assert.FileExists(t, file)
 	conf.RemovePIDFile()
 	os.RemoveAll("dir")

eval/eval.go

@@ -199,15 +199,15 @@ func (e *Evaluator) Evaluate() (bool, error) {
 	if err != nil {
 		return false, err
 	}
-	switch result.(type) {
+	switch r := result.(type) {
 	case bool:
-		return result.(bool), nil
+		return r, nil
 	case float64:
-		return result.(float64) != 0, nil
+		return r != 0, nil
 	case string:
-		return result.(string) != "", nil
+		return r != "", nil
 	}
-	return false, fmt.Errorf("Unsupported type: %T", result)
+	return false, fmt.Errorf("unsupported type: %T", result)
 }
 
 // Extract is the function to extract the value from the document

global/global.go

@@ -192,7 +192,7 @@ func EnumUnmarshalJSON[T comparable](b []byte, m map[string]T, v *T, init T, typ
 func (t *TLS) Config() (*tls.Config, error) {
 	if len(t.CA) <= 0 {
 		// the insecure is true but no ca/cert/key, then return a tls config
-		if t.Insecure == true {
+		if t.Insecure {
 			log.Debug("[TLS] Insecure is true but the CA is empty, return a tls config")
 			return &tls.Config{InsecureSkipVerify: true}, nil
 		}

metric/prometheus.go

@@ -34,11 +34,8 @@ type MetricsType interface {
 }
 
 var (
-	registries   = make([]*prometheus.Registry, 0)
-	counterMap   = make(map[string]*prometheus.CounterVec)
-	gaugeMap     = make(map[string]*prometheus.GaugeVec)
-	histogramMap = make(map[string]*prometheus.HistogramVec)
-	summaryMap   = make(map[string]*prometheus.SummaryVec)
+	counterMap = make(map[string]*prometheus.CounterVec)
+	gaugeMap   = make(map[string]*prometheus.GaugeVec)
 )
 
 var (
@@ -127,12 +124,12 @@ func mergeLabels(labels []string, constLabels prometheus.Labels) []string {
 
 func getAndValid(namespace, subsystem, name, metric string, labels []string, constLabels prometheus.Labels) (string, error) {
 	metricName := GetName(namespace, subsystem, name, metric)
-	if ValidMetricName(metricName) == false {
+	if !ValidMetricName(metricName) {
 		return "", fmt.Errorf("invalid metric name: %s", metricName)
 	}
 
 	for _, l := range labels {
-		if ValidLabelName(l) == false {
+		if !ValidLabelName(l) {
 			return "", fmt.Errorf("invalid label name: %s", l)
 		}
 	}

notify/email/email_test.go

@@ -37,10 +37,6 @@ func (mwc *MyWriteCloser) Close() error {
 func (mwc *MyWriteCloser) Write(p []byte) (n int, err error) {
 	return len(p), nil
 }
-func assertError(t *testing.T, err error, msg string) {
-	assert.Error(t, err)
-	assert.Equal(t, msg, err.Error())
-}
 
 func TestEmail(t *testing.T) {
 	conf := &NotifyConfig{}

notify/log/log_unix.go

@@ -65,7 +65,7 @@ func (c *NotifyConfig) IsSyslog() bool {
 // HasNetwork returns true if the log has network configuration
 func (c *NotifyConfig) HasNetwork() bool {
 	// if is not syslog, then return false
-	if c.IsSyslog() == false {
+	if !c.IsSyslog() {
 		return false
 	}
 	// if is syslog, but not configured network, then return false
@@ -88,7 +88,7 @@ func (c *NotifyConfig) ConfigLog() error {
 	hasNetwork := c.HasNetwork()
 
 	// syslog && network configuration error
-	if isSyslog == true && hasNetwork == true { // remote syslog
+	if isSyslog && hasNetwork { // remote syslog
 		c.NotifyKind = syslogIdentifier
 		c.Type = SysLog
 		if err := c.checkNetworkProtocol(); err != nil {
@@ -101,7 +101,7 @@ func (c *NotifyConfig) ConfigLog() error {
 		}
 		c.logger.SetOutput(writer)
 		log.Infof("[%s / %s] - remote syslog (%s:%s) configured", c.Kind(), c.Name(), c.Network, c.Host)
-	} else if isSyslog == true { // only for local syslog
+	} else if isSyslog { // only for local syslog
 		c.NotifyKind = syslogIdentifier
 		c.Type = SysLog
 		writer, err := syslog.New(syslog.LOG_NOTICE, global.GetEaseProbe().Name)

notify/shell/shell.go

@@ -71,7 +71,7 @@ func (c *NotifyConfig) RunShell(title, msg string) error {
 		env = append(env, fmt.Sprintf("%s=%s", k, v))
 	}
 	cmd.Stdin = strings.NewReader(envMap["EASEPROBE_CSV"])
-	if c.CleanEnv == false {
+	if !c.CleanEnv {
 		cmd.Env = append(os.Environ(), env...)
 	} else {
 		log.Infof("[%s / %s] clean the environment variables", c.NotifyKind, c.NotifyName)

probe/base/base.go

@@ -118,21 +118,21 @@ func (d *DefaultProbe) CheckStatusThreshold() probe.Status {
 	log.Debugf("%s - Status Threshold Checking - Current[%v], StatusCnt[%d], FailureThread[%d], SuccessThread[%d]",
 		title, c.CurrentStatus, c.StatusCount, s.Failure, s.Success)
 
-	if c.CurrentStatus == true && c.StatusCount >= s.Success {
+	if c.CurrentStatus && c.StatusCount >= s.Success {
 		if d.ProbeResult.Status != probe.StatusUp {
 			cnt := math.Max(float64(c.StatusCount), float64(s.Success))
 			log.Infof("%s - Status is UP! Threshold reached for success [%d/%d]", title, int(cnt), s.Success)
 		}
 		return probe.StatusUp
 	}
-	if c.CurrentStatus == false && c.StatusCount >= s.Failure {
+	if !c.CurrentStatus && c.StatusCount >= s.Failure {
 		if d.ProbeResult.Status != probe.StatusDown {
 			cnt := math.Max(float64(c.StatusCount), float64(s.Failure))
 			log.Infof("%s - Status is DOWN! Threshold reached for failure [%d/%d]", title, int(cnt), s.Failure)
 		}
 		return probe.StatusDown
 	}
-	if c.CurrentStatus == true {
+	if c.CurrentStatus {
 		log.Infof("%s - Status unchanged [%s]! Threshold is not reached for success [%d/%d].",
 			title, d.ProbeResult.PreStatus, c.StatusCount, s.Success)
 	} else {

probe/client/memcache/memcache_test.go

@@ -108,7 +108,7 @@ func TestMemcache(t *testing.T) {
 
 	m.Data = map[string]string{}
 	m.ProbeTimeout = time.Second
-	s, msg = m.Probe()
+	s, _ = m.Probe()
 	assert.False(t, s)
 
 	monkey.PatchInstanceMethod(reflect.TypeOf(mc), "Ping", func(*memcache.Client) error {

probe/client/mongo/mongo_test.go

@@ -78,6 +78,7 @@ func TestMongo(t *testing.T) {
 
 	conf.Password = ""
 	mg, err = New(conf)
+	assert.Nil(t, err)
 	connStr = fmt.Sprintf("mongodb://%s/?connectTimeoutMS=%d",
 		conf.Host, conf.Timeout().Milliseconds())
 	assert.Equal(t, connStr, mg.ConnStr)
@@ -92,6 +93,7 @@ func TestMongo(t *testing.T) {
 	})
 
 	mg, err = New(conf)
+	assert.Nil(t, err)
 	assert.Equal(t, "Mongo", mg.Kind())
 	assert.Equal(t, connStr, mg.ConnStr)
 	assert.NotNil(t, mg.ClientOpt.TLSConfig)
@@ -175,6 +177,7 @@ func TestDta(t *testing.T) {
 		"database:collection": "{\"key\" : \"value\"}",
 	}
 	mg, err = New(conf)
+	assert.Nil(t, err)
 	s, m := mg.Probe()
 	assert.True(t, s)
 	assert.Contains(t, m, "Successfully")

probe/client/mysql/mysql_test.go

@@ -59,7 +59,7 @@ func TestMySQL(t *testing.T) {
 	assert.Equal(t, connStr, my.ConnStr)
 
 	conf.Password = ""
-	my, err = New(conf)
+	my, _ = New(conf)
 	connStr = fmt.Sprintf("%s@tcp(%s)/?timeout=%s",
 		conf.Username, conf.Host, conf.Timeout().Round(time.Second))
 	assert.Equal(t, connStr, my.ConnStr)
@@ -95,7 +95,7 @@ func TestMySQL(t *testing.T) {
 		return nil
 	})
 
-	my, err = New(conf)
+	my, _ = New(conf)
 	assert.NotNil(t, my.tls)
 	s, m = my.Probe()
 	assert.True(t, s)
@@ -146,21 +146,24 @@ func TestData(t *testing.T) {
 			"": "",
 		},
 	}
-	my, err := New(conf)
+	var my *MySQL
+	var err error
+
+	_, err = New(conf)
 	assert.NotNil(t, err)
 	assert.Contains(t, err.Error(), "Empty SQL data")
 
 	conf.Data = map[string]string{
 		"key": "value",
 	}
-	my, err = New(conf)
+	_, err = New(conf)
 	assert.NotNil(t, err)
 	assert.Contains(t, err.Error(), "Invalid SQL data")
 
 	conf.Data = map[string]string{
 		"database:table:column:key:value": "expected",
 	}
-	my, err = New(conf)
+	_, err = New(conf)
 	assert.NotNil(t, err)
 	assert.Contains(t, err.Error(), "the value must be int")
 
@@ -186,7 +189,7 @@ func TestData(t *testing.T) {
 	conf.Data = map[string]string{
 		"database:table:column:key:1": "expected",
 	}
-	my, err = New(conf)
+	my, _ = New(conf)
 	s, m := my.Probe()
 	assert.True(t, s)
 	assert.Contains(t, m, "Successfully")

probe/client/postgres/postgres_test.go

@@ -96,7 +96,7 @@ func TestPostgreSQL(t *testing.T) {
 		return &tls.Config{}, nil
 	})
 
-	pg, err = New(conf)
+	pg, _ = New(conf)
 	pgd = pgdriver.NewConnector(pg.ClientOptions...)
 	assert.True(t, pgd.Config().TLSConfig.InsecureSkipVerify)
 
@@ -186,7 +186,7 @@ func TestData(t *testing.T) {
 	conf.Data = map[string]string{
 		"database:table:column:key:1": "expected",
 	}
-	pg, err = New(conf)
+	pg, _ = New(conf)
 	s, m := pg.Probe()
 	assert.True(t, s)
 	assert.Contains(t, m, "Successfully")

probe/client/zookeeper/zookeeper_test.go

@@ -66,7 +66,6 @@ func TestZooKeeper(t *testing.T) {
 		return []byte("test"), &zk.Stat{}, nil
 	})
 	monkey.PatchInstanceMethod(reflect.TypeOf(conn), "Close", func(_ *zk.Conn) {
-		return
 	})
 
 	monkey.Patch(zk.ConnectWithDialer, func(servers []string, sessionTimeout time.Duration, dialer zk.Dialer) (*zk.Conn, <-chan zk.Event, error) {
@@ -178,7 +177,6 @@ func TestData(t *testing.T) {
 	})
 	var conn *zk.Conn
 	monkey.PatchInstanceMethod(reflect.TypeOf(conn), "Close", func(_ *zk.Conn) {
-		return
 	})
 	monkey.PatchInstanceMethod(reflect.TypeOf(conn), "Get", func(_ *zk.Conn, path string) ([]byte, *zk.Stat, error) {
 		return []byte("test"), &zk.Stat{}, nil