fix: lint errors after upgrading golangci-lint (#12368)

.golangci.yml

@@ -12,7 +12,7 @@ linters:
     - goimports
     - misspell
     - govet
-    - golint
+    - revive
     - ineffassign
     - gosimple
     - deadcode
@@ -22,6 +22,7 @@ linters:
     - unused
     - structcheck
     - unconvert
+    - varcheck
 
 issues:
   exclude-use-default: false

Makefile

@@ -16,7 +16,7 @@ checks:
 
 getdeps:
 	@mkdir -p ${GOPATH}/bin
-	@which golangci-lint 1>/dev/null || (echo "Installing golangci-lint" && curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(GOPATH)/bin v1.27.0)
+	@echo "Installing golangci-lint" && curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(GOPATH)/bin v1.40.1
 	@which msgp 1>/dev/null || (echo "Installing msgp" && go install -v github.com/tinylib/msgp@v1.1.3)
 	@which stringer 1>/dev/null || (echo "Installing stringer" && go install -v golang.org/x/tools/cmd/stringer)
 

cmd/config/config.go

@@ -315,10 +315,7 @@ func (c Config) DelFrom(r io.Reader) error {
 			return err
 		}
 	}
-	if err := scanner.Err(); err != nil {
-		return err
-	}
-	return nil
+	return scanner.Err()
 }
 
 // ReadConfig - read content from input and write into c.

cmd/config/identity/ldap/config.go

@@ -189,7 +189,7 @@ func (l *Config) lookupBind(conn *ldap.Conn) error {
 		err = conn.Bind(l.LookupBindDN, l.LookupBindPassword)
 	}
 	if ldap.IsErrorWithCode(err, 49) {
-		return fmt.Errorf("LDAP Lookup Bind user invalid credentials error: %v", err)
+		return fmt.Errorf("LDAP Lookup Bind user invalid credentials error: %w", err)
 	}
 	return err
 }
@@ -214,7 +214,7 @@ func (l *Config) usernameFormatsBind(conn *ldap.Conn, username, password string)
 			bindDistNames = append(bindDistNames, bindDN)
 			successCount++
 		} else if !ldap.IsErrorWithCode(errs[i], 49) {
-			return "", fmt.Errorf("LDAP Bind request failed with unexpected error: %v", errs[i])
+			return "", fmt.Errorf("LDAP Bind request failed with unexpected error: %w", errs[i])
 		}
 	}
 	if successCount == 0 {
@@ -279,7 +279,7 @@ func (l *Config) searchForUserGroups(conn *ldap.Conn, username, bindDN string) (
 			var newGroups []string
 			newGroups, err := getGroups(conn, searchRequest)
 			if err != nil {
-				errRet := fmt.Errorf("Error finding groups of %s: %v", bindDN, err)
+				errRet := fmt.Errorf("Error finding groups of %s: %w", bindDN, err)
 				return nil, errRet
 			}
 
@@ -341,14 +341,14 @@ func (l *Config) Bind(username, password string) (string, []string, error) {
 		// Lookup user DN
 		bindDN, err = l.lookupUserDN(conn, username)
 		if err != nil {
-			errRet := fmt.Errorf("Unable to find user DN: %s", err)
+			errRet := fmt.Errorf("Unable to find user DN: %w", err)
 			return "", nil, errRet
 		}
 
 		// Authenticate the user credentials.
 		err = conn.Bind(bindDN, password)
 		if err != nil {
-			errRet := fmt.Errorf("LDAP auth failed for DN %s: %v", bindDN, err)
+			errRet := fmt.Errorf("LDAP auth failed for DN %s: %w", bindDN, err)
 			return "", nil, errRet
 		}
 
@@ -366,7 +366,7 @@ func (l *Config) Bind(username, password string) (string, []string, error) {
 		// Bind to the successful bindDN again.
 		err = conn.Bind(bindDN, password)
 		if err != nil {
-			errRet := fmt.Errorf("LDAP conn failed though auth for DN %s succeeded: %v", bindDN, err)
+			errRet := fmt.Errorf("LDAP conn failed though auth for DN %s succeeded: %w", bindDN, err)
 			return "", nil, errRet
 		}
 	}
@@ -423,12 +423,12 @@ func (l Config) GetExpiryDuration() time.Duration {
 func (l Config) testConnection() error {
 	conn, err := l.Connect()
 	if err != nil {
-		return fmt.Errorf("Error creating connection to LDAP server: %v", err)
+		return fmt.Errorf("Error creating connection to LDAP server: %w", err)
 	}
 	defer conn.Close()
 	if l.isUsingLookupBind {
 		if err = l.lookupBind(conn); err != nil {
-			return fmt.Errorf("Error connecting as LDAP Lookup Bind user: %v", err)
+			return fmt.Errorf("Error connecting as LDAP Lookup Bind user: %w", err)
 		}
 		return nil
 	}
@@ -449,7 +449,7 @@ func (l Config) testConnection() error {
 	} else if strings.HasPrefix(err.Error(), "All username formats failed due to invalid credentials: ") {
 		return nil
 	}
-	return fmt.Errorf("LDAP connection test error: %v", err)
+	return fmt.Errorf("LDAP connection test error: %w", err)
 }
 
 // Enabled returns if jwks is enabled.
@@ -547,7 +547,7 @@ func Lookup(kvs config.KVS, rootCAs *x509.CertPool) (l Config, err error) {
 
 	// Test connection to LDAP server.
 	if err := l.testConnection(); err != nil {
-		return l, fmt.Errorf("Connection test for LDAP server failed: %v", err)
+		return l, fmt.Errorf("Connection test for LDAP server failed: %w", err)
 	}
 
 	// Group search params configuration

cmd/config/notify/legacy.go

@@ -27,7 +27,7 @@ import (
 )
 
 // SetNotifyKafka - helper for config migration from older config.
-func SetNotifyKafka(s config.Config, kName string, cfg target.KafkaArgs) error {
+func SetNotifyKafka(s config.Config, name string, cfg target.KafkaArgs) error {
 	if !cfg.Enable {
 		return nil
 	}
@@ -36,7 +36,7 @@ func SetNotifyKafka(s config.Config, kName string, cfg target.KafkaArgs) error {
 		return err
 	}
 
-	s[config.NotifyKafkaSubSys][kName] = config.KVS{
+	s[config.NotifyKafkaSubSys][name] = config.KVS{
 		config.KV{
 			Key:   config.Enable,
 			Value: config.EnableOn,

cmd/erasure-server-pool.go

@@ -622,7 +622,7 @@ func (z *erasureServerPools) GetObjectNInfo(ctx context.Context, bucket, object
 	}
 	wg.Wait()
 
-	var found int = -1
+	var found = -1
 	for i, err := range errs {
 		if err == nil {
 			found = i
@@ -683,7 +683,7 @@ func (z *erasureServerPools) GetObjectInfo(ctx context.Context, bucket, object s
 	}
 	wg.Wait()
 
-	var found int = -1
+	var found = -1
 	for i, err := range errs {
 		if err == nil {
 			found = i

cmd/format-disk-cache.go

@@ -495,8 +495,5 @@ func migrateCacheFormatJSON(cacheFormatPath string) error {
 	formatV2.Version = formatMetaVersion1
 	formatV2.Cache = formatV1.Cache
 	formatV2.Cache.Version = formatCacheVersionV2
-	if err := jsonSave(f, formatV2); err != nil {
-		return err
-	}
-	return nil
+	return jsonSave(f, formatV2)
 }

cmd/tier.go

@@ -49,7 +49,7 @@ const (
 )
 
 // tierConfigPath refers to remote tier config object name
-var tierConfigPath string = path.Join(minioConfigPrefix, tierConfigFile)
+var tierConfigPath = path.Join(minioConfigPrefix, tierConfigFile)
 
 // TierConfigMgr holds the collection of remote tiers configured in this deployment.
 type TierConfigMgr struct {

pkg/bucket/replication/rule.go

@@ -140,10 +140,7 @@ func (r Rule) validateStatus() error {
 }
 
 func (r Rule) validateFilter() error {
-	if err := r.Filter.Validate(); err != nil {
-		return err
-	}
-	return nil
+	return r.Filter.Validate()
 }
 
 // Prefix - a rule can either have prefix under <filter></filter> or under

pkg/event/target/amqp.go

@@ -205,16 +205,12 @@ func (target *AMQPTarget) send(eventData event.Event, ch *amqp.Channel) error {
 		return err
 	}
 
-	if err := ch.Publish(target.args.Exchange, target.args.RoutingKey, target.args.Mandatory,
+	return ch.Publish(target.args.Exchange, target.args.RoutingKey, target.args.Mandatory,
 		target.args.Immediate, amqp.Publishing{
 			ContentType:  "application/json",
 			DeliveryMode: target.args.DeliveryMode,
 			Body:         data,
-		}); err != nil {
-		return err
-	}
-
-	return nil
+		})
 }
 
 // Save - saves the events to the store which will be replayed when the amqp connection is active.

pkg/s3select/csv/record.go

@@ -103,11 +103,7 @@ func (r *Record) WriteCSV(writer io.Writer, opts sql.WriteCSVOpts) error {
 		return err
 	}
 	w.Flush()
-	if err := w.Error(); err != nil {
-		return err
-	}
-
-	return nil
+	return w.Error()
 }
 
 // WriteJSON - encodes to JSON data.

pkg/s3select/json/record.go

@@ -145,11 +145,7 @@ func (r *Record) WriteCSV(writer io.Writer, opts sql.WriteCSVOpts) error {
 		return err
 	}
 	w.Flush()
-	if err := w.Error(); err != nil {
-		return err
-	}
-
-	return nil
+	return w.Error()
 }
 
 // Raw - returns the underlying representation.

pkg/s3select/simdj/record.go

@@ -181,11 +181,7 @@ allElems:
 		return err
 	}
 	w.Flush()
-	if err := w.Error(); err != nil {
-		return err
-	}
-
-	return nil
+	return w.Error()
 }
 
 // Raw - returns the underlying representation.