replace golangci-lint with staticcheck, errcheck and unparam

Signed-off-by: Nicola Murino <nicola.murino@gmail.com>

Author: drakkan

.errcheck-excludes

@@ -0,0 +1,58 @@
+# Functions whose returned error carries no decision: writes to an in-memory
+# buffer, which cannot fail, and resource teardown, where the caller has
+# already given up the resource. Every other discarded error is written as an
+# explicit blank assignment at the call site.
+
+# writes that cannot fail
+(bytes.Buffer).WriteString
+(hash.Hash).Write
+(strings.Builder).Write
+(strings.Builder).WriteByte
+(strings.Builder).WriteString
+fmt.Fprintf
+fmt.Printf
+fmt.Println
+
+# resource teardown
+(*cloud.google.com/go/storage.Reader).Close
+(*database/sql.Conn).Close
+(*database/sql.Rows).Close
+(*database/sql.Stmt).Close
+(*database/sql.Tx).Rollback
+(*github.com/drakkan/sftpgo/v2/internal/common.BaseConnection).CloseFS
+(*github.com/drakkan/sftpgo/v2/internal/common.DirListerAt).Close
+(*github.com/drakkan/sftpgo/v2/internal/dataprovider.User).CloseFs
+(*github.com/drakkan/sftpgo/v2/internal/httpd.Connection).CloseFS
+(*github.com/drakkan/sftpgo/v2/internal/sftpd.Connection).CloseFS
+(*github.com/drakkan/sftpgo/v2/internal/sftpd.transfer).Close
+(*github.com/drakkan/sftpgo/v2/internal/vfs.SFTPFs).Close
+(*github.com/pkg/sftp.File).Close
+(*github.com/pkg/sftp.RequestServer).Close
+(*gocloud.dev/secrets.Keeper).Close
+(*golang.org/x/crypto/ssh.Client).Close
+(*golang.org/x/crypto/ssh.ServerConn).Close
+(*golang.org/x/sys/windows/svc/mgr.Mgr).Disconnect
+(*golang.org/x/sys/windows/svc/mgr.Service).Close
+(*io.PipeWriter).Close
+(*mime/multipart.Form).RemoveAll
+(*mime/multipart.Writer).Close
+(*os.File).Close
+(github.com/drakkan/sftpgo/v2/internal/dataprovider.User).CloseFs
+(github.com/drakkan/sftpgo/v2/internal/vfs.DirLister).Close
+(github.com/drakkan/sftpgo/v2/internal/vfs.Fs).Close
+(github.com/drakkan/sftpgo/v2/internal/vfs.PipeWriter).Close
+(github.com/drakkan/sftpgo/v2/internal/vfs.pipeReaderAt).Close
+(github.com/drakkan/sftpgo/v2/internal/vfs.pipeReaderAt).CloseWithError
+(github.com/drakkan/sftpgo/v2/internal/vfs.pipeWriterAt).Close
+(github.com/drakkan/sftpgo/v2/internal/vfs.pipeWriterAt).CloseWithError
+(io.Closer).Close
+(io.ReadCloser).Close
+(io.ReadWriteCloser).Close
+(io.WriteCloser).Close
+(mime/multipart.File).Close
+(net.Conn).Close
+(net.Listener).Close
+(net/http.File).Close
+
+# Close promoted from an embedded type: errcheck names the declaring type
+(golang.org/x/crypto/ssh.Conn).Close

.github/workflows/development.yml

@@ -547,16 +547,42 @@ jobs:
           name: sftpgo-${{ steps.build_linux_pkgs.outputs.pkg-version }}-${{ matrix.go-arch }}-rpm
           path: pkgs/dist/rpm/*
 
-  golangci-lint:
-    name: golangci-lint
+  lint:
+    name: lint
     runs-on: ubuntu-latest
+
     steps:
+      - uses: actions/checkout@v7
+
       - name: Set up Go
         uses: actions/setup-go@v7
         with:
           go-version: '1.26'
-      - uses: actions/checkout@v7
-      - name: Run golangci-lint
-        uses: golangci/golangci-lint-action@v9
-        with:
-          version: latest
+
+      - name: Lint
+        run: |
+          export PATH="$(go env GOPATH)/bin:$PATH"
+          go install honnef.co/go/tools/cmd/staticcheck@v0.8.1
+          go install github.com/kisielk/errcheck@v1.20.0
+          go install mvdan.cc/unparam@v0.0.0-20260823230713-2fa3d841b0c8
+
+          set +e
+          rc=0
+          flags="-ignoretests -exclude .errcheck-excludes"
+
+          echo "==> go vet";                  go vet ./... || rc=1
+          echo "==> staticcheck";             staticcheck ./... || rc=1
+          echo "==> errcheck";                errcheck $flags ./... || rc=1
+          echo "==> unparam"
+          out=$(unparam -tests ./... | grep -vFf .unparam-excludes)
+          [ -z "$out" ] || { echo "$out"; rc=1; }
+
+          echo "==> go vet (windows)";        GOOS=windows go vet ./... || rc=1
+          echo "==> staticcheck (windows)";   GOOS=windows staticcheck ./... || rc=1
+          echo "==> errcheck (windows)";      GOOS=windows errcheck $flags ./... || rc=1
+
+          echo "==> gofmt"
+          out=$(gofmt -s -l .)
+          [ -z "$out" ] || { echo "$out"; rc=1; }
+
+          exit $rc

.golangci.yml

@@ -0,0 +1 @@
+streamJSONArray - chunkSize always receives

.unparam-excludes

@@ -103,10 +103,10 @@ func getCustomServeFlags() []string {
 		result = append(result, "--"+logLevelFlag)
 		result = append(result, logLevel)
 	}
-	if logUTCTime != defaultLogUTCTime {
+	if logUTCTime {
 		result = append(result, "--"+logUTCTimeFlag+"=true")
 	}
-	if logCompress != defaultLogCompress {
+	if logCompress {
 		result = append(result, "--"+logCompressFlag+"=true")
 	}
 	if graceTime != defaultGraceTime {

internal/cmd/install_windows.go

@@ -122,7 +122,7 @@ Please take a look at the usage below to customize the options.`,
 func init() {
 	addConfigFlags(resetPwdCmd)
 	resetPwdCmd.Flags().StringVar(&resetPwdAdmin, "admin", "", `Administrator username whose password to reset`)
-	resetPwdCmd.MarkFlagRequired("admin") //nolint:errcheck
+	_ = resetPwdCmd.MarkFlagRequired("admin")
 
 	rootCmd.AddCommand(resetPwdCmd)
 }

internal/cmd/resetpwd.go

@@ -111,7 +111,7 @@ func Execute() {
 
 func addConfigFlags(cmd *cobra.Command) {
 	viper.SetDefault(configDirKey, defaultConfigDir)
-	viper.BindEnv(configDirKey, "SFTPGO_CONFIG_DIR") //nolint:errcheck // err is not nil only if the key to bind is missing
+	_ = viper.BindEnv(configDirKey, "SFTPGO_CONFIG_DIR") // err is not nil only if the key to bind is missing
 	cmd.Flags().StringVarP(&configDir, configDirFlag, "c", viper.GetString(configDirKey),
 		`Location of the config dir. This directory
 is used as the base for files with a relative
@@ -127,10 +127,10 @@ file name is "sftpgo" and therefore
 searched.
 This flag can be set using SFTPGO_CONFIG_DIR
 env var too.`)
-	viper.BindPFlag(configDirKey, cmd.Flags().Lookup(configDirFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(configDirKey, cmd.Flags().Lookup(configDirFlag))
 
 	viper.SetDefault(configFileKey, defaultConfigFile)
-	viper.BindEnv(configFileKey, "SFTPGO_CONFIG_FILE") //nolint:errcheck
+	_ = viper.BindEnv(configFileKey, "SFTPGO_CONFIG_FILE")
 	cmd.Flags().StringVar(&configFile, configFileFlag, viper.GetString(configFileKey),
 		`Path to SFTPGo configuration file.
 This flag explicitly defines the path, name
@@ -141,12 +141,12 @@ name must have a supported extension (JSON,
 YAML, TOML, HCL or Java properties).
 This flag can be set using SFTPGO_CONFIG_FILE
 env var too.`)
-	viper.BindPFlag(configFileKey, cmd.Flags().Lookup(configFileFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(configFileKey, cmd.Flags().Lookup(configFileFlag))
 }
 
 func addBaseLoadDataFlags(cmd *cobra.Command) {
 	viper.SetDefault(loadDataFromKey, defaultLoadDataFrom)
-	viper.BindEnv(loadDataFromKey, "SFTPGO_LOADDATA_FROM") //nolint:errcheck
+	_ = viper.BindEnv(loadDataFromKey, "SFTPGO_LOADDATA_FROM")
 	cmd.Flags().StringVar(&loadDataFrom, loadDataFromFlag, viper.GetString(loadDataFromKey),
 		`Load users and folders from this file.
 The file must be specified as absolute path
@@ -155,10 +155,10 @@ the "dumpdata" REST API or compatible content.
 This flag can be set using SFTPGO_LOADDATA_FROM
 env var too.
 `)
-	viper.BindPFlag(loadDataFromKey, cmd.Flags().Lookup(loadDataFromFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(loadDataFromKey, cmd.Flags().Lookup(loadDataFromFlag))
 
 	viper.SetDefault(loadDataModeKey, defaultLoadDataMode)
-	viper.BindEnv(loadDataModeKey, "SFTPGO_LOADDATA_MODE") //nolint:errcheck
+	_ = viper.BindEnv(loadDataModeKey, "SFTPGO_LOADDATA_MODE")
 	cmd.Flags().IntVar(&loadDataMode, loadDataModeFlag, viper.GetInt(loadDataModeKey),
 		`Restore mode for data to load:
   0 - new users are added, existing users are
@@ -168,71 +168,71 @@ env var too.
 This flag can be set using SFTPGO_LOADDATA_MODE
 env var too.
 `)
-	viper.BindPFlag(loadDataModeKey, cmd.Flags().Lookup(loadDataModeFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(loadDataModeKey, cmd.Flags().Lookup(loadDataModeFlag))
 
 	viper.SetDefault(loadDataCleanKey, defaultLoadDataClean)
-	viper.BindEnv(loadDataCleanKey, "SFTPGO_LOADDATA_CLEAN") //nolint:errcheck
+	_ = viper.BindEnv(loadDataCleanKey, "SFTPGO_LOADDATA_CLEAN")
 	cmd.Flags().BoolVar(&loadDataClean, loadDataCleanFlag, viper.GetBool(loadDataCleanKey),
 		`Determine if the loaddata-from file should
 be removed after a successful load. This flag
 can be set using SFTPGO_LOADDATA_CLEAN env var
 too. (default "false")
 `)
-	viper.BindPFlag(loadDataCleanKey, cmd.Flags().Lookup(loadDataCleanFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(loadDataCleanKey, cmd.Flags().Lookup(loadDataCleanFlag))
 }
 
 func addServeFlags(cmd *cobra.Command) {
 	addConfigFlags(cmd)
 
 	viper.SetDefault(logFilePathKey, defaultLogFile)
-	viper.BindEnv(logFilePathKey, "SFTPGO_LOG_FILE_PATH") //nolint:errcheck
+	_ = viper.BindEnv(logFilePathKey, "SFTPGO_LOG_FILE_PATH")
 	cmd.Flags().StringVarP(&logFilePath, logFilePathFlag, "l", viper.GetString(logFilePathKey),
 		`Location for the log file. Leave empty to write
 logs to the standard output. This flag can be
 set using SFTPGO_LOG_FILE_PATH env var too.
 `)
-	viper.BindPFlag(logFilePathKey, cmd.Flags().Lookup(logFilePathFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(logFilePathKey, cmd.Flags().Lookup(logFilePathFlag))
 
 	viper.SetDefault(logMaxSizeKey, defaultLogMaxSize)
-	viper.BindEnv(logMaxSizeKey, "SFTPGO_LOG_MAX_SIZE") //nolint:errcheck
+	_ = viper.BindEnv(logMaxSizeKey, "SFTPGO_LOG_MAX_SIZE")
 	cmd.Flags().IntVarP(&logMaxSize, logMaxSizeFlag, "s", viper.GetInt(logMaxSizeKey),
 		`Maximum size in megabytes of the log file
 before it gets rotated. This flag can be set
 using SFTPGO_LOG_MAX_SIZE env var too. It is
 unused if log-file-path is empty.
 `)
-	viper.BindPFlag(logMaxSizeKey, cmd.Flags().Lookup(logMaxSizeFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(logMaxSizeKey, cmd.Flags().Lookup(logMaxSizeFlag))
 
 	viper.SetDefault(logMaxBackupKey, defaultLogMaxBackup)
-	viper.BindEnv(logMaxBackupKey, "SFTPGO_LOG_MAX_BACKUPS") //nolint:errcheck
+	_ = viper.BindEnv(logMaxBackupKey, "SFTPGO_LOG_MAX_BACKUPS")
 	cmd.Flags().IntVarP(&logMaxBackups, "log-max-backups", "b", viper.GetInt(logMaxBackupKey),
 		`Maximum number of old log files to retain.
 This flag can be set using SFTPGO_LOG_MAX_BACKUPS
 env var too. It is unused if log-file-path is
 empty.`)
-	viper.BindPFlag(logMaxBackupKey, cmd.Flags().Lookup(logMaxBackupFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(logMaxBackupKey, cmd.Flags().Lookup(logMaxBackupFlag))
 
 	viper.SetDefault(logMaxAgeKey, defaultLogMaxAge)
-	viper.BindEnv(logMaxAgeKey, "SFTPGO_LOG_MAX_AGE") //nolint:errcheck
+	_ = viper.BindEnv(logMaxAgeKey, "SFTPGO_LOG_MAX_AGE")
 	cmd.Flags().IntVarP(&logMaxAge, "log-max-age", "a", viper.GetInt(logMaxAgeKey),
 		`Maximum number of days to retain old log files.
 This flag can be set using SFTPGO_LOG_MAX_AGE env
 var too. It is unused if log-file-path is empty.
 `)
-	viper.BindPFlag(logMaxAgeKey, cmd.Flags().Lookup(logMaxAgeFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(logMaxAgeKey, cmd.Flags().Lookup(logMaxAgeFlag))
 
 	viper.SetDefault(logCompressKey, defaultLogCompress)
-	viper.BindEnv(logCompressKey, "SFTPGO_LOG_COMPRESS") //nolint:errcheck
+	_ = viper.BindEnv(logCompressKey, "SFTPGO_LOG_COMPRESS")
 	cmd.Flags().BoolVarP(&logCompress, logCompressFlag, "z", viper.GetBool(logCompressKey),
 		`Determine if the rotated log files
 should be compressed using gzip. This flag can
 be set using SFTPGO_LOG_COMPRESS env var too.
 It is unused if log-file-path is empty.
 `)
-	viper.BindPFlag(logCompressKey, cmd.Flags().Lookup(logCompressFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(logCompressKey, cmd.Flags().Lookup(logCompressFlag))
 
 	viper.SetDefault(logLevelKey, defaultLogLevel)
-	viper.BindEnv(logLevelKey, "SFTPGO_LOG_LEVEL") //nolint:errcheck
+	_ = viper.BindEnv(logLevelKey, "SFTPGO_LOG_LEVEL")
 	cmd.Flags().StringVar(&logLevel, logLevelFlag, viper.GetString(logLevelKey),
 		`Set the log level. Supported values:
 
@@ -241,20 +241,20 @@ debug, info, warn, error.
 This flag can be set
 using SFTPGO_LOG_LEVEL env var too.
 `)
-	viper.BindPFlag(logLevelKey, cmd.Flags().Lookup(logLevelFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(logLevelKey, cmd.Flags().Lookup(logLevelFlag))
 
 	viper.SetDefault(logUTCTimeKey, defaultLogUTCTime)
-	viper.BindEnv(logUTCTimeKey, "SFTPGO_LOG_UTC_TIME") //nolint:errcheck
+	_ = viper.BindEnv(logUTCTimeKey, "SFTPGO_LOG_UTC_TIME")
 	cmd.Flags().BoolVar(&logUTCTime, logUTCTimeFlag, viper.GetBool(logUTCTimeKey),
 		`Use UTC time for logging. This flag can be set
 using SFTPGO_LOG_UTC_TIME env var too.
 `)
-	viper.BindPFlag(logUTCTimeKey, cmd.Flags().Lookup(logUTCTimeFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(logUTCTimeKey, cmd.Flags().Lookup(logUTCTimeFlag))
 
 	addBaseLoadDataFlags(cmd)
 
 	viper.SetDefault(loadDataQuotaScanKey, defaultLoadDataQuotaScan)
-	viper.BindEnv(loadDataQuotaScanKey, "SFTPGO_LOADDATA_QUOTA_SCAN") //nolint:errcheck
+	_ = viper.BindEnv(loadDataQuotaScanKey, "SFTPGO_LOADDATA_QUOTA_SCAN")
 	cmd.Flags().IntVar(&loadDataQuotaScan, loadDataQuotaScanFlag, viper.GetInt(loadDataQuotaScanKey),
 		`Quota scan mode after data load:
   0 - no quota scan
@@ -263,10 +263,10 @@ using SFTPGO_LOG_UTC_TIME env var too.
 This flag can be set using SFTPGO_LOADDATA_QUOTA_SCAN
 env var too.
 (default 0)`)
-	viper.BindPFlag(loadDataQuotaScanKey, cmd.Flags().Lookup(loadDataQuotaScanFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(loadDataQuotaScanKey, cmd.Flags().Lookup(loadDataQuotaScanFlag))
 
 	viper.SetDefault(graceTimeKey, defaultGraceTime)
-	viper.BindEnv(graceTimeKey, "SFTPGO_GRACE_TIME") //nolint:errcheck
+	_ = viper.BindEnv(graceTimeKey, "SFTPGO_GRACE_TIME")
 	cmd.Flags().IntVar(&graceTime, graceTimeFlag, viper.GetInt(graceTimeKey),
 		`Graceful shutdown is an option to initiate a
 shutdown without abrupt cancellation of the
@@ -279,5 +279,5 @@ A graceful shutdown is triggered by an
 interrupt signal.
 This flag can be set using SFTPGO_GRACE_TIME env
 var too. 0 means disabled. (default 0)`)
-	viper.BindPFlag(graceTimeKey, cmd.Flags().Lookup(graceTimeFlag)) //nolint:errcheck
+	_ = viper.BindPFlag(graceTimeKey, cmd.Flags().Lookup(graceTimeFlag))
 }

internal/cmd/root.go

@@ -86,7 +86,7 @@ func setBoolFromEnv(receiver *bool, val string) {
 	}
 }
 
-func checkServeParamsFromEnvFiles(configDir string) { //nolint:gocyclo
+func checkServeParamsFromEnvFiles(configDir string) {
 	// The logger is not yet initialized here, we have no way to report errors.
 	envd := filepath.Join(configDir, "env.d")
 	entries, err := os.ReadDir(envd)

internal/cmd/serve.go

@@ -70,7 +70,7 @@ If the SMTP configuration is correct you should receive this email.`,
 func init() {
 	addConfigFlags(smtpTestCmd)
 	smtpTestCmd.Flags().StringVar(&smtpTestRecipient, "recipient", "", `email address to send the test e-mail to`)
-	smtpTestCmd.MarkFlagRequired("recipient") //nolint:errcheck
+	_ = smtpTestCmd.MarkFlagRequired("recipient")
 
 	rootCmd.AddCommand(smtpTestCmd)
 }