refact: remove unused struct fields and params / 3; enable linter "unused" (#3334)

* lint: configure unused linter
* Remove unused AlertContext.Log field
* unused consoleOptions
* unused isSwarmManager
* unused withCurrentYear - rfc5424 has it by spec
* unused collectionName
* unused notificationConfigsByPluginType
* unused local vars
* unused: windows build

Author: mmetc

.golangci.yml

@@ -168,6 +168,29 @@ linters:
         ifElseChain:
           minThreshold: 4
 
+    unused:
+      # Mark all struct fields that have been written to as used.
+      # Default: true
+      field-writes-are-uses: false
+      # Treat IncDec statement (e.g. `i++` or `i--`) as both read and write operation instead of just write.
+      # Default: false
+      post-statements-are-reads: false
+      # Mark all exported identifiers as used.
+      # Default: true
+      # exported-is-used: false
+      # Mark all exported fields as used.
+      # default: true
+      exported-fields-are-used: false
+      # Mark all function parameters as used.
+      # default: true
+      parameters-are-used: true
+      # Mark all local variables as used.
+      # default: true
+      local-variables-are-used: false
+      # Mark all identifiers inside generated files as used.
+      # Default: true
+      generated-is-used: false
+
     gomoddirectives:
       replace-allow-list:
         - golang.org/x/time

cmd/crowdsec-cli/clihubtest/table.go

@@ -58,13 +58,10 @@ func hubTestCoverageTable(out io.Writer, wantColor string, headers []string, cov
 	t.SetHeaderAlignment(text.AlignLeft, text.AlignLeft, text.AlignLeft)
 	t.SetAlignment(text.AlignLeft, text.AlignLeft, text.AlignLeft)
 
-	parserTested := 0
-
 	for _, test := range coverage {
 		status := emoji.RedCircle
 		if test.TestsCount > 0 {
 			status = emoji.GreenCircle
-			parserTested++
 		}
 
 		t.AddRow(test.Name, status, fmt.Sprintf("%d times (across %d tests)", test.TestsCount, len(test.PresentIn)))

cmd/crowdsec-cli/dashboard_unsupported.go

@@ -10,13 +10,10 @@ import (
 )
 
 type cliDashboard struct{
-	cfg configGetter
 }
 
-func NewCLIDashboard(cfg configGetter) *cliDashboard {
-	return &cliDashboard{
-		cfg: cfg,
-	}
+func NewCLIDashboard(_ configGetter) *cliDashboard {
+	return &cliDashboard{}
 }
 
 func (cli cliDashboard) NewCommand() *cobra.Command {

cmd/crowdsec/lpmetrics.go

@@ -52,7 +52,6 @@ type staticMetrics struct {
 	osVersion      string
 	startupTS      int64
 	featureFlags   []string
-	consoleOptions []string
 	datasourceMap  map[string]int64
 	hubState       models.HubItems
 }
@@ -104,7 +103,6 @@ func newStaticMetrics(consoleOptions []string, datasources []acquisition.DataSou
 		osVersion:      osVersion,
 		startupTS:      time.Now().UTC().Unix(),
 		featureFlags:   fflag.Crowdsec.GetEnabledFeatures(),
-		consoleOptions: consoleOptions,
 		datasourceMap:  datasourceMap,
 		hubState:       getHubState(hub),
 	}

pkg/acquisition/modules/docker/docker_test.go

@@ -200,7 +200,6 @@ func TestConfigureDSN(t *testing.T) {
 
 type mockDockerCli struct {
 	client.Client
-	isSwarmManager bool
 	services       []dockerTypesSwarm.Service
 }
 
@@ -348,8 +347,7 @@ service_name_regexp:
 				return
 			}
 
-			mockClient := &mockDockerCli{isSwarmManager: ts.isSwarmManager}
-			dockerSource.Client = mockClient
+			dockerSource.Client = &mockDockerCli{}
 
 			// Manually set swarm manager flag for testing since Info() mock is simplified
 			dockerSource.isSwarmManager = ts.isSwarmManager
@@ -496,8 +494,7 @@ use_service_labels: true`,
 			err := f.Configure(ctx, []byte(test.config), subLogger, metrics.AcquisitionMetricsLevelNone)
 			require.NoError(t, err)
 
-			mockClient := &mockDockerCli{isSwarmManager: test.isSwarmManager}
-			f.Client = mockClient
+			f.Client = &mockDockerCli{}
 
 			// Manually set swarm manager flag for testing
 			f.isSwarmManager = test.isSwarmManager
@@ -567,10 +564,9 @@ service_name:
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
 			subLogger := log.WithField("type", "docker")
-			f := DockerSource{}
-
-			mockClient := &mockDockerCli{isSwarmManager: test.isSwarmManager}
-			f.Client = mockClient
+			f := DockerSource{
+				Client: &mockDockerCli{},
+			}
 
 			err := f.Configure(ctx, []byte(test.config), subLogger, metrics.AcquisitionMetricsLevelNone)
 			require.NoError(t, err)

pkg/acquisition/modules/syslog/internal/parser/rfc5424/parse.go

@@ -21,7 +21,6 @@ type RFC5424 struct {
 	len            int
 	position       int
 	buf            []byte
-	useCurrentYear bool //If no year is specified in the timestamp, use the current year
 	strictHostname bool //If the hostname contains invalid characters or is not an IP, return an error
 }
 
@@ -35,12 +34,6 @@ var VALID_TIMESTAMPS = []string{
 
 const VALID_TIMESTAMP = time.RFC3339Nano
 
-func WithCurrentYear() RFC5424Option {
-	return func(r *RFC5424) {
-		r.useCurrentYear = true
-	}
-}
-
 func WithStrictHostname() RFC5424Option {
 	return func(r *RFC5424) {
 		r.strictHostname = true

pkg/alertcontext/alertcontext.go

@@ -25,7 +25,6 @@ type Context struct {
 	ContextToSend         map[string][]string
 	ContextValueLen       int
 	ContextToSendCompiled map[string][]*vm.Program
-	Log                   *log.Logger
 }
 
 func ValidateContextExpr(key string, expressions []string) error {
@@ -44,25 +43,19 @@ func ValidateContextExpr(key string, expressions []string) error {
 }
 
 func NewAlertContext(contextToSend map[string][]string, valueLength int) error {
-	clog := log.New()
-	if err := types.ConfigureLogger(clog, 0); err != nil {
-		return fmt.Errorf("couldn't create logger for alert context: %w", err)
-	}
-
 	if valueLength == 0 {
-		clog.Debugf("No console context value length provided, using default: %d", MaxContextValueLen)
+		log.Debugf("No console context value length provided, using default: %d", MaxContextValueLen)
 		valueLength = MaxContextValueLen
 	}
 
 	if valueLength > MaxContextValueLen {
-		clog.Debugf("Provided console context value length (%d) is higher than the maximum, using default: %d", valueLength, MaxContextValueLen)
+		log.Debugf("Provided console context value length (%d) is higher than the maximum, using default: %d", valueLength, MaxContextValueLen)
 		valueLength = MaxContextValueLen
 	}
 
 	alertContext = Context{
 		ContextToSend:         contextToSend,
 		ContextValueLen:       valueLength,
-		Log:                   clog,
 		ContextToSendCompiled: make(map[string][]*vm.Program),
 	}
 

pkg/appsec/appsec_rules_collection.go

@@ -13,7 +13,6 @@ import (
 )
 
 type AppsecCollection struct {
-	collectionName string
 	Rules          []string
 	NativeRules    []string
 }
@@ -70,9 +69,7 @@ func LoadCollection(pattern string, logger *log.Entry) ([]AppsecCollection, erro
 			continue
 		}
 
-		appsecCol := AppsecCollection{
-			collectionName: appsecRule.Name,
-		}
+		appsecCol := AppsecCollection{}
 
 		if appsecRule.SecLangFilesRules != nil {
 			for _, rulesFile := range appsecRule.SecLangFilesRules {

pkg/csplugin/broker.go

@@ -45,7 +45,6 @@ type PluginBroker struct {
 	profileConfigs                  []*csconfig.ProfileCfg
 	pluginConfigByName              map[string]PluginConfig
 	pluginMap                       map[string]plugin.Plugin
-	notificationConfigsByPluginType map[string][][]byte // "slack" -> []{config1, config2}
 	notificationPluginByName        map[string]protobufs.NotifierServer
 	watcher                         PluginWatcher
 	pluginKillMethods               []func()
@@ -96,7 +95,6 @@ type PluginConfigList []PluginConfig
 
 func (pb *PluginBroker) Init(ctx context.Context, pluginCfg *csconfig.PluginCfg, profileConfigs []*csconfig.ProfileCfg, configPaths *csconfig.ConfigurationPaths) error {
 	pb.PluginChannel = make(chan models.ProfileAlert)
-	pb.notificationConfigsByPluginType = make(map[string][][]byte)
 	pb.notificationPluginByName = make(map[string]protobufs.NotifierServer)
 	pb.pluginMap = make(map[string]plugin.Plugin)
 	pb.pluginConfigByName = make(map[string]PluginConfig)

pkg/csplugin/utils_windows.go

@@ -21,10 +21,15 @@ import (
 
 var (
 	advapi32 = syscall.NewLazyDLL("advapi32.dll")
-
 	procGetAce = advapi32.NewProc("GetAce")
 )
 
+var _ = func() any {
+	var pb PluginBroker
+	_ = pb.pluginProcConfig // reference to silence unused linter
+	return nil
+}()
+
 type AclSizeInformation struct {
 	AceCount      uint32
 	AclBytesInUse uint32