Linter fixes - revive:unused-parameter, unparam, varcheck and unused (#8984)

* Linter fixes - revive:unused-parameter and unparam

* Linter fixes - revive:unused-parameter and unparam

* Linter fixes - revive:unused-parameter and unparam

* "nolint"'s removed

* Fixes for "varcheck" and "unused" added.

* Fixes for "varcheck" and "unused" added.

* Fixes for "varcheck" and "unused" added.

* Fixes for "varcheck" and "unused" added.

* Fixes for "varcheck" and "unused" added.

* Fixes for "varcheck" and "unused" added.

* Fixes for "varcheck" and "unused" added.

Co-authored-by: Pawel Zak <Pawel Zak>

.golangci.yml

@@ -1,4 +1,5 @@
 linters:
+  disable-all: true
   enable:
     - bodyclose
     - dogsled
@@ -18,55 +19,6 @@ linters:
     - unparam
     - unused
     - varcheck
-  disable:
-    - asciicheck
-    - deadcode
-    - depguard
-    - dupl
-    - exhaustive
-    - funlen
-    - gci
-    - gochecknoglobals
-    - gochecknoinits
-    - gocognit
-    - goconst
-    - gocritic
-    - gocyclo
-    - godot
-    - godox
-    - goerr113
-    - gofmt
-    - gofumpt
-    - goheader
-    - goimports
-    - golint
-    - gomnd
-    - gomodguard
-    - gosec
-    - ifshort
-    - interfacer
-    - lll
-    - makezero
-    - maligned
-    - megacheck
-    - misspell
-    - nestif
-    - nlreturn
-    - noctx
-    - nolintlint
-    - paralleltest
-    - prealloc
-    - rowserrcheck
-    - scopelint
-    - structcheck
-    - stylecheck
-    - testpackage
-    - thelper
-    - tparallel
-    - wastedassign
-    - whitespace
-    - wrapcheck
-    - wsl
 
 linters-settings:
   revive:
@@ -131,7 +83,7 @@ linters-settings:
 
 run:
   # timeout for analysis, e.g. 30s, 5m, default is 1m
-  timeout: 5m
+  timeout: 10m
 
   # which dirs to skip: issues from them won't be reported;
   # can use regexp here: generated.*, regexp is applied on full path;
@@ -169,10 +121,8 @@ issues:
       linters:
         - govet
 
-  # Show only new issues created after git revision `HEAD~`
-  # Great for CI setups
-  # It's not practical to fix all existing issues at the moment of integration: much better to not allow issues in new code.
-  # new-from-rev: "HEAD~"
+    - path: _test\.go
+      text: "parameter.*seems to be a control flag, avoid control coupling"
 
 output:
   format: tab

agent/agent.go

@@ -126,10 +126,7 @@ func (a *Agent) Run(ctx context.Context) error {
 			}
 		}
 
-		next, au, err = a.startAggregators(aggC, next, a.Config.Aggregators)
-		if err != nil {
-			return err
-		}
+		next, au = a.startAggregators(aggC, next, a.Config.Aggregators)
 	}
 
 	var pu []*processorUnit
@@ -149,29 +146,20 @@ func (a *Agent) Run(ctx context.Context) error {
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		err := a.runOutputs(ou)
-		if err != nil {
-			log.Printf("E! [agent] Error running outputs: %v", err)
-		}
+		a.runOutputs(ou)
 	}()
 
 	if au != nil {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runProcessors(apu)
-			if err != nil {
-				log.Printf("E! [agent] Error running processors: %v", err)
-			}
+			a.runProcessors(apu)
 		}()
 
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runAggregators(startTime, au)
-			if err != nil {
-				log.Printf("E! [agent] Error running aggregators: %v", err)
-			}
+			a.runAggregators(startTime, au)
 		}()
 	}
 
@@ -179,20 +167,14 @@ func (a *Agent) Run(ctx context.Context) error {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runProcessors(pu)
-			if err != nil {
-				log.Printf("E! [agent] Error running processors: %v", err)
-			}
+			a.runProcessors(pu)
 		}()
 	}
 
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		err := a.runInputs(ctx, startTime, iu)
-		if err != nil {
-			log.Printf("E! [agent] Error running inputs: %v", err)
-		}
+		a.runInputs(ctx, startTime, iu)
 	}()
 
 	wg.Wait()
@@ -288,7 +270,7 @@ func (a *Agent) runInputs(
 	ctx context.Context,
 	startTime time.Time,
 	unit *inputUnit,
-) error {
+) {
 	var wg sync.WaitGroup
 	for _, input := range unit.inputs {
 		// Overwrite agent interval if this plugin has its own.
@@ -334,8 +316,6 @@ func (a *Agent) runInputs(
 
 	close(unit.dst)
 	log.Printf("D! [agent] Input channel closed")
-
-	return nil
 }
 
 // testStartInputs is a variation of startInputs for use in --test and --once
@@ -344,7 +324,7 @@ func (a *Agent) runInputs(
 func (a *Agent) testStartInputs(
 	dst chan<- telegraf.Metric,
 	inputs []*models.RunningInput,
-) (*inputUnit, error) {
+) *inputUnit {
 	log.Printf("D! [agent] Starting service inputs")
 
 	unit := &inputUnit{
@@ -369,7 +349,7 @@ func (a *Agent) testStartInputs(
 		unit.inputs = append(unit.inputs, input)
 	}
 
-	return unit, nil
+	return unit
 }
 
 // testRunInputs is a variation of runInputs for use in --test and --once mode.
@@ -378,7 +358,7 @@ func (a *Agent) testRunInputs(
 	ctx context.Context,
 	wait time.Duration,
 	unit *inputUnit,
-) error {
+) {
 	var wg sync.WaitGroup
 
 	nul := make(chan telegraf.Metric)
@@ -434,7 +414,6 @@ func (a *Agent) testRunInputs(
 
 	close(unit.dst)
 	log.Printf("D! [agent] Input channel closed")
-	return nil
 }
 
 // stopServiceInputs stops all service inputs.
@@ -553,7 +532,7 @@ func (a *Agent) startProcessors(
 // closed and all metrics have been written.
 func (a *Agent) runProcessors(
 	units []*processorUnit,
-) error {
+) {
 	var wg sync.WaitGroup
 	for _, unit := range units {
 		wg.Add(1)
@@ -573,8 +552,6 @@ func (a *Agent) runProcessors(
 		}(unit)
 	}
 	wg.Wait()
-
-	return nil
 }
 
 // startAggregators sets up the aggregator unit and returns the source channel.
@@ -582,7 +559,7 @@ func (a *Agent) startAggregators(
 	aggC chan<- telegraf.Metric,
 	outputC chan<- telegraf.Metric,
 	aggregators []*models.RunningAggregator,
-) (chan<- telegraf.Metric, *aggregatorUnit, error) {
+) (chan<- telegraf.Metric, *aggregatorUnit) {
 	src := make(chan telegraf.Metric, 100)
 	unit := &aggregatorUnit{
 		src:         src,
@@ -590,7 +567,7 @@ func (a *Agent) startAggregators(
 		outputC:     outputC,
 		aggregators: aggregators,
 	}
-	return src, unit, nil
+	return src, unit
 }
 
 // runAggregators beings aggregating metrics and runs until the source channel
@@ -598,7 +575,7 @@ func (a *Agent) startAggregators(
 func (a *Agent) runAggregators(
 	startTime time.Time,
 	unit *aggregatorUnit,
-) error {
+) {
 	ctx, cancel := context.WithCancel(context.Background())
 
 	// Before calling Add, initialize the aggregation window.  This ensures
@@ -650,8 +627,6 @@ func (a *Agent) runAggregators(
 	// processor chain will close the outputC when it finishes processing.
 	close(unit.aggC)
 	log.Printf("D! [agent] Aggregator channel closed")
-
-	return nil
 }
 
 func updateWindow(start time.Time, roundInterval bool, period time.Duration) (time.Time, time.Time) {
@@ -744,7 +719,7 @@ func (a *Agent) connectOutput(ctx context.Context, output *models.RunningOutput)
 // written one last time and dropped if unsuccessful.
 func (a *Agent) runOutputs(
 	unit *outputUnit,
-) error {
+) {
 	var wg sync.WaitGroup
 
 	// Start flush loop
@@ -793,8 +768,6 @@ func (a *Agent) runOutputs(
 
 	log.Println("I! [agent] Stopping running outputs")
 	stopRunningOutputs(unit.outputs)
-
-	return nil
 }
 
 // flushLoop runs an output's flush function periodically until the context is
@@ -924,10 +897,7 @@ func (a *Agent) test(ctx context.Context, wait time.Duration, outputC chan<- tel
 			}
 		}
 
-		next, au, err = a.startAggregators(procC, next, a.Config.Aggregators)
-		if err != nil {
-			return err
-		}
+		next, au = a.startAggregators(procC, next, a.Config.Aggregators)
 	}
 
 	var pu []*processorUnit
@@ -938,30 +908,20 @@ func (a *Agent) test(ctx context.Context, wait time.Duration, outputC chan<- tel
 		}
 	}
 
-	iu, err := a.testStartInputs(next, a.Config.Inputs)
-	if err != nil {
-		return err
-	}
+	iu := a.testStartInputs(next, a.Config.Inputs)
 
 	var wg sync.WaitGroup
-
 	if au != nil {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runProcessors(apu)
-			if err != nil {
-				log.Printf("E! [agent] Error running processors: %v", err)
-			}
+			a.runProcessors(apu)
 		}()
 
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runAggregators(startTime, au)
-			if err != nil {
-				log.Printf("E! [agent] Error running aggregators: %v", err)
-			}
+			a.runAggregators(startTime, au)
 		}()
 	}
 
@@ -969,20 +929,14 @@ func (a *Agent) test(ctx context.Context, wait time.Duration, outputC chan<- tel
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runProcessors(pu)
-			if err != nil {
-				log.Printf("E! [agent] Error running processors: %v", err)
-			}
+			a.runProcessors(pu)
 		}()
 	}
 
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		err := a.testRunInputs(ctx, wait, iu)
-		if err != nil {
-			log.Printf("E! [agent] Error running inputs: %v", err)
-		}
+		a.testRunInputs(ctx, wait, iu)
 	}()
 
 	wg.Wait()
@@ -1042,10 +996,7 @@ func (a *Agent) once(ctx context.Context, wait time.Duration) error {
 			}
 		}
 
-		next, au, err = a.startAggregators(procC, next, a.Config.Aggregators)
-		if err != nil {
-			return err
-		}
+		next, au = a.startAggregators(procC, next, a.Config.Aggregators)
 	}
 
 	var pu []*processorUnit
@@ -1056,38 +1007,26 @@ func (a *Agent) once(ctx context.Context, wait time.Duration) error {
 		}
 	}
 
-	iu, err := a.testStartInputs(next, a.Config.Inputs)
-	if err != nil {
-		return err
-	}
+	iu := a.testStartInputs(next, a.Config.Inputs)
 
 	var wg sync.WaitGroup
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		err := a.runOutputs(ou)
-		if err != nil {
-			log.Printf("E! [agent] Error running outputs: %v", err)
-		}
+		a.runOutputs(ou)
 	}()
 
 	if au != nil {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runProcessors(apu)
-			if err != nil {
-				log.Printf("E! [agent] Error running processors: %v", err)
-			}
+			a.runProcessors(apu)
 		}()
 
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runAggregators(startTime, au)
-			if err != nil {
-				log.Printf("E! [agent] Error running aggregators: %v", err)
-			}
+			a.runAggregators(startTime, au)
 		}()
 	}
 
@@ -1095,20 +1034,14 @@ func (a *Agent) once(ctx context.Context, wait time.Duration) error {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			err := a.runProcessors(pu)
-			if err != nil {
-				log.Printf("E! [agent] Error running processors: %v", err)
-			}
+			a.runProcessors(pu)
 		}()
 	}
 
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		err := a.testRunInputs(ctx, wait, iu)
-		if err != nil {
-			log.Printf("E! [agent] Error running inputs: %v", err)
-		}
+		a.testRunInputs(ctx, wait, iu)
 	}()
 
 	wg.Wait()

agent/tick.go

@@ -9,8 +9,6 @@ import (
 	"github.com/influxdata/telegraf/internal"
 )
 
-type empty struct{}
-
 type Ticker interface {
 	Elapsed() <-chan time.Time
 	Stop()

cmd/telegraf/telegraf.go

@@ -61,11 +61,22 @@ var fProcessorFilters = flag.String("processor-filter", "",
 	"filter the processors to enable, separator is :")
 var fUsage = flag.String("usage", "",
 	"print usage for a plugin, ie, 'telegraf --usage mysql'")
+
+//nolint:varcheck,unused // False positive - this var is used for non-default build tag: windows
 var fService = flag.String("service", "",
 	"operate on the service (windows only)")
-var fServiceName = flag.String("service-name", "telegraf", "service name (windows only)")
-var fServiceDisplayName = flag.String("service-display-name", "Telegraf Data Collector Service", "service display name (windows only)")
-var fRunAsConsole = flag.Bool("console", false, "run as console application (windows only)")
+
+//nolint:varcheck,unused // False positive - this var is used for non-default build tag: windows
+var fServiceName = flag.String("service-name", "telegraf",
+	"service name (windows only)")
+
+//nolint:varcheck,unused // False positive - this var is used for non-default build tag: windows
+var fServiceDisplayName = flag.String("service-display-name", "Telegraf Data Collector Service",
+	"service display name (windows only)")
+
+//nolint:varcheck,unused // False positive - this var is used for non-default build tag: windows
+var fRunAsConsole = flag.Bool("console", false,
+	"run as console application (windows only)")
 var fPlugins = flag.String("plugin-directory", "",
 	"path to directory containing external plugins")
 var fRunOnce = flag.Bool("once", false, "run one gather and exit")
@@ -81,14 +92,11 @@ var stop chan struct{}
 func reloadLoop(
 	inputFilters []string,
 	outputFilters []string,
-	aggregatorFilters []string,
-	processorFilters []string,
 ) {
 	reload := make(chan bool, 1)
 	reload <- true
 	for <-reload {
 		reload <- false
-
 		ctx, cancel := context.WithCancel(context.Background())
 
 		signals := make(chan os.Signal, 1)
@@ -363,7 +371,5 @@ func main() {
 	run(
 		inputFilters,
 		outputFilters,
-		aggregatorFilters,
-		processorFilters,
 	)
 }

cmd/telegraf/telegraf_posix.go

@@ -2,12 +2,10 @@
 
 package main
 
-func run(inputFilters, outputFilters, aggregatorFilters, processorFilters []string) {
+func run(inputFilters, outputFilters []string) {
 	stop = make(chan struct{})
 	reloadLoop(
 		inputFilters,
 		outputFilters,
-		aggregatorFilters,
-		processorFilters,
 	)
 }

cmd/telegraf/telegraf_windows.go

@@ -11,7 +11,7 @@ import (
 	"github.com/kardianos/service"
 )
 
-func run(inputFilters, outputFilters, aggregatorFilters, processorFilters []string) {
+func run(inputFilters, outputFilters []string) {
 	// Register the eventlog logging target for windows.
 	logger.RegisterEventLogger(*fServiceName)
 
@@ -19,25 +19,19 @@ func run(inputFilters, outputFilters, aggregatorFilters, processorFilters []stri
 		runAsWindowsService(
 			inputFilters,
 			outputFilters,
-			aggregatorFilters,
-			processorFilters,
 		)
 	} else {
 		stop = make(chan struct{})
 		reloadLoop(
 			inputFilters,
 			outputFilters,
-			aggregatorFilters,
-			processorFilters,
 		)
 	}
 }
 
 type program struct {
-	inputFilters      []string
-	outputFilters     []string
-	aggregatorFilters []string
-	processorFilters  []string
+	inputFilters  []string
+	outputFilters []string
 }
 
 func (p *program) Start(s service.Service) error {
@@ -49,8 +43,6 @@ func (p *program) run() {
 	reloadLoop(
 		p.inputFilters,
 		p.outputFilters,
-		p.aggregatorFilters,
-		p.processorFilters,
 	)
 }
 func (p *program) Stop(s service.Service) error {
@@ -58,7 +50,7 @@ func (p *program) Stop(s service.Service) error {
 	return nil
 }
 
-func runAsWindowsService(inputFilters, outputFilters, aggregatorFilters, processorFilters []string) {
+func runAsWindowsService(inputFilters, outputFilters []string) {
 	programFiles := os.Getenv("ProgramFiles")
 	if programFiles == "" { // Should never happen
 		programFiles = "C:\\Program Files"
@@ -72,10 +64,8 @@ func runAsWindowsService(inputFilters, outputFilters, aggregatorFilters, process
 	}
 
 	prg := &program{
-		inputFilters:      inputFilters,
-		outputFilters:     outputFilters,
-		aggregatorFilters: aggregatorFilters,
-		processorFilters:  processorFilters,
+		inputFilters:  inputFilters,
+		outputFilters: outputFilters,
 	}
 	s, err := service.New(prg, svcConfig)
 	if err != nil {

config/config.go

@@ -1006,14 +1006,14 @@ func (c *Config) addProcessor(name string, table *ast.Table) error {
 		return err
 	}
 
-	rf, err := c.newRunningProcessor(creator, processorConfig, name, table)
+	rf, err := c.newRunningProcessor(creator, processorConfig, table)
 	if err != nil {
 		return err
 	}
 	c.Processors = append(c.Processors, rf)
 
 	// save a copy for the aggregator
-	rf, err = c.newRunningProcessor(creator, processorConfig, name, table)
+	rf, err = c.newRunningProcessor(creator, processorConfig, table)
 	if err != nil {
 		return err
 	}
@@ -1025,7 +1025,6 @@ func (c *Config) addProcessor(name string, table *ast.Table) error {
 func (c *Config) newRunningProcessor(
 	creator processors.StreamingCreator,
 	processorConfig *models.ProcessorConfig,
-	name string,
 	table *ast.Table,
 ) (*models.RunningProcessor, error) {
 	processor := creator()
@@ -1058,7 +1057,7 @@ func (c *Config) addOutput(name string, table *ast.Table) error {
 	// arbitrary types of output, so build the serializer and set it.
 	switch t := output.(type) {
 	case serializers.SerializerOutput:
-		serializer, err := c.buildSerializer(name, table)
+		serializer, err := c.buildSerializer(table)
 		if err != nil {
 			return err
 		}
@@ -1074,8 +1073,7 @@ func (c *Config) addOutput(name string, table *ast.Table) error {
 		return err
 	}
 
-	ro := models.NewRunningOutput(name, output, outputConfig,
-		c.Agent.MetricBatchSize, c.Agent.MetricBufferLimit)
+	ro := models.NewRunningOutput(output, outputConfig, c.Agent.MetricBatchSize, c.Agent.MetricBufferLimit)
 	c.Outputs = append(c.Outputs, ro)
 	return nil
 }
@@ -1377,8 +1375,8 @@ func (c *Config) getParserConfig(name string, tbl *ast.Table) (*parsers.Config,
 // buildSerializer grabs the necessary entries from the ast.Table for creating
 // a serializers.Serializer object, and creates it, which can then be added onto
 // an Output object.
-func (c *Config) buildSerializer(name string, tbl *ast.Table) (serializers.Serializer, error) {
-	sc := &serializers.Config{TimestampUnits: time.Duration(1 * time.Second)}
+func (c *Config) buildSerializer(tbl *ast.Table) (serializers.Serializer, error) {
+	sc := &serializers.Config{TimestampUnits: 1 * time.Second}
 
 	c.getFieldString(tbl, "data_format", &sc.DataFormat)
 
@@ -1449,7 +1447,7 @@ func (c *Config) buildOutput(name string, tbl *ast.Table) (*models.OutputConfig,
 	return oc, nil
 }
 
-func (c *Config) missingTomlField(typ reflect.Type, key string) error {
+func (c *Config) missingTomlField(_ reflect.Type, key string) error {
 	switch key {
 	case "alias", "carbon2_format", "collectd_auth_file", "collectd_parse_multivalue",
 		"collectd_security_level", "collectd_typesdb", "collection_jitter", "csv_column_names",

internal/goplugin/noplugin.go

@@ -4,6 +4,6 @@ package goplugin
 
 import "errors"
 
-func LoadExternalPlugins(rootDir string) error {
+func LoadExternalPlugins(_ string) error {
 	return errors.New("go plugin support is not enabled")
 }

internal/internal_test.go

@@ -46,7 +46,7 @@ func TestSnakeCase(t *testing.T) {
 }
 
 var (
-	sleepbin, _ = exec.LookPath("sleep")
+	sleepbin, _ = exec.LookPath("sleep") //nolint:unused // Used in skipped tests
 	echobin, _  = exec.LookPath("echo")
 	shell, _    = exec.LookPath("sh")
 )

metric/metric.go

@@ -251,8 +251,8 @@ func (m *metric) Copy() telegraf.Metric {
 	return m2
 }
 
-func (m *metric) SetAggregate(b bool) {
-	m.aggregate = true
+func (m *metric) SetAggregate(aggregate bool) {
+	m.aggregate = aggregate
 }
 
 func (m *metric) IsAggregate() bool {

metric/tracking_test.go

@@ -78,12 +78,13 @@ func TestTracking(t *testing.T) {
 		{
 			name: "accept",
 			metric: mustMetric(
-				"cpu",
+				"memory",
 				map[string]string{},
 				map[string]interface{}{
 					"value": 42,
 				},
 				time.Unix(0, 0),
+				telegraf.Gauge,
 			),
 			actions: func(m telegraf.Metric) {
 				m.Accept()
@@ -93,12 +94,13 @@ func TestTracking(t *testing.T) {
 		{
 			name: "reject",
 			metric: mustMetric(
-				"cpu",
+				"memory",
 				map[string]string{},
 				map[string]interface{}{
 					"value": 42,
 				},
 				time.Unix(0, 0),
+				telegraf.Gauge,
 			),
 			actions: func(m telegraf.Metric) {
 				m.Reject()
@@ -108,12 +110,13 @@ func TestTracking(t *testing.T) {
 		{
 			name: "accept copy",
 			metric: mustMetric(
-				"cpu",
+				"memory",
 				map[string]string{},
 				map[string]interface{}{
 					"value": 42,
 				},
 				time.Unix(0, 0),
+				telegraf.Gauge,
 			),
 			actions: func(m telegraf.Metric) {
 				m2 := m.Copy()
@@ -125,12 +128,13 @@ func TestTracking(t *testing.T) {
 		{
 			name: "copy with accept and done",
 			metric: mustMetric(
-				"cpu",
+				"memory",
 				map[string]string{},
 				map[string]interface{}{
 					"value": 42,
 				},
 				time.Unix(0, 0),
+				telegraf.Gauge,
 			),
 			actions: func(m telegraf.Metric) {
 				m2 := m.Copy()
@@ -142,12 +146,13 @@ func TestTracking(t *testing.T) {
 		{
 			name: "copy with mixed delivery",
 			metric: mustMetric(
-				"cpu",
+				"memory",
 				map[string]string{},
 				map[string]interface{}{
 					"value": 42,
 				},
 				time.Unix(0, 0),
+				telegraf.Gauge,
 			),
 			actions: func(m telegraf.Metric) {
 				m2 := m.Copy()

models/buffer.go

@@ -220,16 +220,6 @@ func (b *Buffer) Reject(batch []telegraf.Metric) {
 	b.BufferSize.Set(int64(b.length()))
 }
 
-// dist returns the distance between two indexes.  Because this data structure
-// uses a half open range the arguments must both either left side or right
-// side pairs.
-func (b *Buffer) dist(begin, end int) int {
-	if begin <= end {
-		return end - begin
-	}
-	return b.cap - begin + end
-}
-
 // next returns the next index with wrapping.
 func (b *Buffer) next(index int) int {
 	index++
@@ -246,15 +236,6 @@ func (b *Buffer) nextby(index, count int) int {
 	return index
 }
 
-// next returns the prev index with wrapping.
-func (b *Buffer) prev(index int) int {
-	index--
-	if index < 0 {
-		return b.cap - 1
-	}
-	return index
-}
-
 // prevby returns the index that is count older with wrapping.
 func (b *Buffer) prevby(index, count int) int {
 	index -= count

models/running_input_test.go

@@ -289,6 +289,6 @@ func TestMetricErrorCounters(t *testing.T) {
 
 type testInput struct{}
 
-func (t *testInput) Description() string                   { return "" }
-func (t *testInput) SampleConfig() string                  { return "" }
-func (t *testInput) Gather(acc telegraf.Accumulator) error { return nil }
+func (t *testInput) Description() string                 { return "" }
+func (t *testInput) SampleConfig() string                { return "" }
+func (t *testInput) Gather(_ telegraf.Accumulator) error { return nil }

models/running_output.go

@@ -56,7 +56,6 @@ type RunningOutput struct {
 }
 
 func NewRunningOutput(
-	name string,
 	output telegraf.Output,
 	config *OutputConfig,
 	batchSize int,

models/running_output_test.go

@@ -29,14 +29,6 @@ var next5 = []telegraf.Metric{
 	testutil.TestMetric(101, "metric10"),
 }
 
-func reverse(metrics []telegraf.Metric) []telegraf.Metric {
-	result := make([]telegraf.Metric, 0, len(metrics))
-	for i := len(metrics) - 1; i >= 0; i-- {
-		result = append(result, metrics[i])
-	}
-	return result
-}
-
 // Benchmark adding metrics.
 func BenchmarkRunningOutputAddWrite(b *testing.B) {
 	conf := &OutputConfig{
@@ -44,7 +36,7 @@ func BenchmarkRunningOutputAddWrite(b *testing.B) {
 	}
 
 	m := &perfOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	for n := 0; n < b.N; n++ {
 		ro.AddMetric(testutil.TestMetric(101, "metric1"))
@@ -59,7 +51,7 @@ func BenchmarkRunningOutputAddWriteEvery100(b *testing.B) {
 	}
 
 	m := &perfOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	for n := 0; n < b.N; n++ {
 		ro.AddMetric(testutil.TestMetric(101, "metric1"))
@@ -77,7 +69,7 @@ func BenchmarkRunningOutputAddFailWrites(b *testing.B) {
 
 	m := &perfOutput{}
 	m.failWrite = true
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	for n := 0; n < b.N; n++ {
 		ro.AddMetric(testutil.TestMetric(101, "metric1"))
@@ -94,7 +86,7 @@ func TestRunningOutput_DropFilter(t *testing.T) {
 	assert.NoError(t, conf.Filter.Compile())
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	for _, metric := range first5 {
 		ro.AddMetric(metric)
@@ -119,7 +111,7 @@ func TestRunningOutput_PassFilter(t *testing.T) {
 	assert.NoError(t, conf.Filter.Compile())
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	for _, metric := range first5 {
 		ro.AddMetric(metric)
@@ -144,7 +136,7 @@ func TestRunningOutput_TagIncludeNoMatch(t *testing.T) {
 	assert.NoError(t, conf.Filter.Compile())
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	ro.AddMetric(testutil.TestMetric(101, "metric1"))
 	assert.Len(t, m.Metrics(), 0)
@@ -165,7 +157,7 @@ func TestRunningOutput_TagExcludeMatch(t *testing.T) {
 	assert.NoError(t, conf.Filter.Compile())
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	ro.AddMetric(testutil.TestMetric(101, "metric1"))
 	assert.Len(t, m.Metrics(), 0)
@@ -186,7 +178,7 @@ func TestRunningOutput_TagExcludeNoMatch(t *testing.T) {
 	assert.NoError(t, conf.Filter.Compile())
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	ro.AddMetric(testutil.TestMetric(101, "metric1"))
 	assert.Len(t, m.Metrics(), 0)
@@ -207,7 +199,7 @@ func TestRunningOutput_TagIncludeMatch(t *testing.T) {
 	assert.NoError(t, conf.Filter.Compile())
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	ro.AddMetric(testutil.TestMetric(101, "metric1"))
 	assert.Len(t, m.Metrics(), 0)
@@ -225,7 +217,7 @@ func TestRunningOutput_NameOverride(t *testing.T) {
 	}
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	ro.AddMetric(testutil.TestMetric(101, "metric1"))
 	assert.Len(t, m.Metrics(), 0)
@@ -243,7 +235,7 @@ func TestRunningOutput_NamePrefix(t *testing.T) {
 	}
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	ro.AddMetric(testutil.TestMetric(101, "metric1"))
 	assert.Len(t, m.Metrics(), 0)
@@ -261,7 +253,7 @@ func TestRunningOutput_NameSuffix(t *testing.T) {
 	}
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	ro.AddMetric(testutil.TestMetric(101, "metric1"))
 	assert.Len(t, m.Metrics(), 0)
@@ -279,7 +271,7 @@ func TestRunningOutputDefault(t *testing.T) {
 	}
 
 	m := &mockOutput{}
-	ro := NewRunningOutput("test", m, conf, 1000, 10000)
+	ro := NewRunningOutput(m, conf, 1000, 10000)
 
 	for _, metric := range first5 {
 		ro.AddMetric(metric)
@@ -301,7 +293,7 @@ func TestRunningOutputWriteFail(t *testing.T) {
 
 	m := &mockOutput{}
 	m.failWrite = true
-	ro := NewRunningOutput("test", m, conf, 4, 12)
+	ro := NewRunningOutput(m, conf, 4, 12)
 
 	// Fill buffer to limit twice
 	for _, metric := range first5 {
@@ -334,7 +326,7 @@ func TestRunningOutputWriteFailOrder(t *testing.T) {
 
 	m := &mockOutput{}
 	m.failWrite = true
-	ro := NewRunningOutput("test", m, conf, 100, 1000)
+	ro := NewRunningOutput(m, conf, 100, 1000)
 
 	// add 5 metrics
 	for _, metric := range first5 {
@@ -372,7 +364,7 @@ func TestRunningOutputWriteFailOrder2(t *testing.T) {
 
 	m := &mockOutput{}
 	m.failWrite = true
-	ro := NewRunningOutput("test", m, conf, 5, 100)
+	ro := NewRunningOutput(m, conf, 5, 100)
 
 	// add 5 metrics
 	for _, metric := range first5 {
@@ -436,7 +428,7 @@ func TestRunningOutputWriteFailOrder3(t *testing.T) {
 
 	m := &mockOutput{}
 	m.failWrite = true
-	ro := NewRunningOutput("test", m, conf, 5, 1000)
+	ro := NewRunningOutput(m, conf, 5, 1000)
 
 	// add 5 metrics
 	for _, metric := range first5 {
@@ -470,7 +462,6 @@ func TestRunningOutputWriteFailOrder3(t *testing.T) {
 
 func TestInternalMetrics(t *testing.T) {
 	_ = NewRunningOutput(
-		"test_internal",
 		&mockOutput{},
 		&OutputConfig{
 			Filter: Filter{},
@@ -581,7 +572,7 @@ func (m *perfOutput) SampleConfig() string {
 	return ""
 }
 
-func (m *perfOutput) Write(metrics []telegraf.Metric) error {
+func (m *perfOutput) Write(_ []telegraf.Metric) error {
 	if m.failWrite {
 		return fmt.Errorf("failed write")
 	}

plugins/aggregators/merge/merge.go

@@ -19,7 +19,6 @@ const (
 
 type Merge struct {
 	grouper *metric.SeriesGrouper
-	log     telegraf.Logger
 }
 
 func (a *Merge) Init() error {

plugins/aggregators/quantile/algorithms.go

@@ -21,7 +21,7 @@ type exactAlgorithmR7 struct {
 	sorted bool
 }
 
-func newExactR7(compression float64) (algorithm, error) {
+func newExactR7(_ float64) (algorithm, error) {
 	return &exactAlgorithmR7{xs: make([]float64, 0, 100), sorted: false}, nil
 }
 
@@ -68,7 +68,7 @@ type exactAlgorithmR8 struct {
 	sorted bool
 }
 
-func newExactR8(compression float64) (algorithm, error) {
+func newExactR8(_ float64) (algorithm, error) {
 	return &exactAlgorithmR8{xs: make([]float64, 0, 100), sorted: false}, nil
 }
 

plugins/common/shim/config_test.go

@@ -81,7 +81,7 @@ func (i *testDurationInput) SampleConfig() string {
 func (i *testDurationInput) Description() string {
 	return ""
 }
-func (i *testDurationInput) Gather(acc telegraf.Accumulator) error {
+func (i *testDurationInput) Gather(_ telegraf.Accumulator) error {
 	return nil
 }
 

plugins/common/shim/goshim_test.go

@@ -71,7 +71,7 @@ func (i *erroringInput) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (i *erroringInput) Start(acc telegraf.Accumulator) error {
+func (i *erroringInput) Start(_ telegraf.Accumulator) error {
 	return nil
 }
 

plugins/common/shim/input_test.go

@@ -100,7 +100,7 @@ func (i *testInput) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (i *testInput) Start(acc telegraf.Accumulator) error {
+func (i *testInput) Start(_ telegraf.Accumulator) error {
 	return nil
 }
 
@@ -133,7 +133,7 @@ func (i *serviceInput) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (i *serviceInput) Start(acc telegraf.Accumulator) error {
+func (i *serviceInput) Start(_ telegraf.Accumulator) error {
 	return nil
 }
 

plugins/inputs/aerospike/aerospike.go

@@ -486,14 +486,6 @@ func parseAerospikeValue(key string, v string) interface{} {
 	}
 }
 
-func copyTags(m map[string]string) map[string]string {
-	out := make(map[string]string)
-	for k, v := range m {
-		out[k] = v
-	}
-	return out
-}
-
 func init() {
 	inputs.Add("aerospike", func() telegraf.Input {
 		return &Aerospike{}

plugins/inputs/aliyuncms/aliyuncms_test.go

@@ -71,7 +71,7 @@ type mockAliyunSDKCli struct {
 	resp *responses.CommonResponse
 }
 
-func (m *mockAliyunSDKCli) ProcessCommonRequest(req *requests.CommonRequest) (response *responses.CommonResponse, err error) {
+func (m *mockAliyunSDKCli) ProcessCommonRequest(_ *requests.CommonRequest) (response *responses.CommonResponse, err error) {
 	return m.resp, nil
 }
 

plugins/inputs/apcupsd/apcupsd_test.go

@@ -12,7 +12,7 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestApcupsdDocs(t *testing.T) {
+func TestApcupsdDocs(_ *testing.T) {
 	apc := &ApcUpsd{}
 	apc.Description()
 	apc.SampleConfig()

plugins/inputs/cassandra/cassandra_test.go

@@ -77,19 +77,6 @@ const validCassandraNestedMultiValueJSON = `
 	}
 }`
 
-const validSingleValueJSON = `
-{
-  "request":{
-    "path":"used",
-    "mbean":"java.lang:type=Memory",
-    "attribute":"HeapMemoryUsage",
-    "type":"read"
-  },
-  "value":209274376,
-  "timestamp":1446129256,
-  "status":200
-}`
-
 const validJavaMultiTypeJSON = `
 {
    "request":{
@@ -104,8 +91,6 @@ const validJavaMultiTypeJSON = `
 
 const invalidJSON = "I don't think this is JSON"
 
-const empty = ""
-
 var Servers = []string{"10.10.10.10:8778"}
 var AuthServers = []string{"user:passwd@10.10.10.10:8778"}
 var MultipleServers = []string{"10.10.10.10:8778", "10.10.10.11:8778"}
@@ -121,7 +106,7 @@ type jolokiaClientStub struct {
 	statusCode   int
 }
 
-func (c jolokiaClientStub) MakeRequest(req *http.Request) (*http.Response, error) {
+func (c jolokiaClientStub) MakeRequest(_ *http.Request) (*http.Response, error) {
 	resp := http.Response{}
 	resp.StatusCode = c.statusCode
 	resp.Body = ioutil.NopCloser(strings.NewReader(c.responseBody))

plugins/inputs/ceph/ceph_test.go

@@ -86,7 +86,7 @@ func TestDecodeOSDPoolStats(t *testing.T) {
 	}
 }
 
-func TestGather(t *testing.T) {
+func TestGather(_ *testing.T) {
 	saveFind := findSockets
 	saveDump := perfDump
 	defer func() {

plugins/inputs/chrony/chrony_test.go

@@ -65,7 +65,7 @@ func fakeExecCommand(command string, args ...string) *exec.Cmd {
 // For example, if you run:
 // GO_WANT_HELPER_PROCESS=1 go test -test.run=TestHelperProcess -- chrony tracking
 // it returns below mockData.
-func TestHelperProcess(t *testing.T) {
+func TestHelperProcess(_ *testing.T) {
 	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
 		return
 	}

plugins/inputs/cisco_telemetry_mdt/cisco_telemetry_mdt.go

@@ -88,15 +88,15 @@ func (c *CiscoTelemetryMDT) Start(acc telegraf.Accumulator) error {
 	// Invert aliases list
 	c.warned = make(map[string]struct{})
 	c.aliases = make(map[string]string, len(c.Aliases))
-	for alias, path := range c.Aliases {
-		c.aliases[path] = alias
+	for alias, encodingPath := range c.Aliases {
+		c.aliases[encodingPath] = alias
 	}
 	c.initDb()
 
 	c.dmesFuncs = make(map[string]string, len(c.Dmes))
-	for dme, path := range c.Dmes {
-		c.dmesFuncs[path] = dme
-		switch path {
+	for dme, dmeKey := range c.Dmes {
+		c.dmesFuncs[dmeKey] = dme
+		switch dmeKey {
 		case "uint64 to int":
 			c.propMap[dme] = nxosValueXformUint64Toint64
 		case "uint64 to string":
@@ -115,7 +115,7 @@ func (c *CiscoTelemetryMDT) Start(acc telegraf.Accumulator) error {
 			}
 
 			var jsStruct NxPayloadXfromStructure
-			err := json.Unmarshal([]byte(path), &jsStruct)
+			err := json.Unmarshal([]byte(dmeKey), &jsStruct)
 			if err != nil {
 				continue
 			}
@@ -449,9 +449,10 @@ func (c *CiscoTelemetryMDT) parseKeyField(tags map[string]string, field *telemet
 	}
 }
 
-func (c *CiscoTelemetryMDT) parseRib(grouper *metric.SeriesGrouper, field *telemetry.TelemetryField, prefix string, path string, tags map[string]string, timestamp time.Time) {
+func (c *CiscoTelemetryMDT) parseRib(grouper *metric.SeriesGrouper, field *telemetry.TelemetryField,
+	encodingPath string, tags map[string]string, timestamp time.Time) {
 	// RIB
-	measurement := path
+	measurement := encodingPath
 	for _, subfield := range field.Fields {
 		//For Every table fill the keys which are vrfName, address and masklen
 		switch subfield.Name {
@@ -481,13 +482,14 @@ func (c *CiscoTelemetryMDT) parseRib(grouper *metric.SeriesGrouper, field *telem
 	}
 }
 
-func (c *CiscoTelemetryMDT) parseClassAttributeField(grouper *metric.SeriesGrouper, field *telemetry.TelemetryField, prefix string, path string, tags map[string]string, timestamp time.Time) {
+func (c *CiscoTelemetryMDT) parseClassAttributeField(grouper *metric.SeriesGrouper, field *telemetry.TelemetryField,
+	encodingPath string, tags map[string]string, timestamp time.Time) {
 	// DME structure: https://developer.cisco.com/site/nxapi-dme-model-reference-api/
 	var nxAttributes *telemetry.TelemetryField
-	isDme := strings.Contains(path, "sys/")
-	if path == "rib" {
+	isDme := strings.Contains(encodingPath, "sys/")
+	if encodingPath == "rib" {
 		//handle native data path rib
-		c.parseRib(grouper, field, prefix, path, tags, timestamp)
+		c.parseRib(grouper, field, encodingPath, tags, timestamp)
 		return
 	}
 	if field == nil || !isDme || len(field.Fields) == 0 || len(field.Fields[0].Fields) == 0 || len(field.Fields[0].Fields[0].Fields) == 0 {
@@ -503,13 +505,13 @@ func (c *CiscoTelemetryMDT) parseClassAttributeField(grouper *metric.SeriesGroup
 		if subfield.Name == "dn" {
 			tags["dn"] = decodeTag(subfield)
 		} else {
-			c.parseContentField(grouper, subfield, "", path, tags, timestamp)
+			c.parseContentField(grouper, subfield, "", encodingPath, tags, timestamp)
 		}
 	}
 }
 
 func (c *CiscoTelemetryMDT) parseContentField(grouper *metric.SeriesGrouper, field *telemetry.TelemetryField, prefix string,
-	path string, tags map[string]string, timestamp time.Time) {
+	encodingPath string, tags map[string]string, timestamp time.Time) {
 	name := strings.Replace(field.Name, "-", "_", -1)
 
 	if (name == "modTs" || name == "createTs") && decodeValue(field) == "never" {
@@ -521,23 +523,23 @@ func (c *CiscoTelemetryMDT) parseContentField(grouper *metric.SeriesGrouper, fie
 		name = prefix + "/" + name
 	}
 
-	extraTags := c.extraTags[strings.Replace(path, "-", "_", -1)+"/"+name]
+	extraTags := c.extraTags[strings.Replace(encodingPath, "-", "_", -1)+"/"+name]
 
 	if value := decodeValue(field); value != nil {
 		// Do alias lookup, to shorten measurement names
-		measurement := path
-		if alias, ok := c.aliases[path]; ok {
+		measurement := encodingPath
+		if alias, ok := c.aliases[encodingPath]; ok {
 			measurement = alias
 		} else {
 			c.mutex.Lock()
-			if _, haveWarned := c.warned[path]; !haveWarned {
-				c.Log.Debugf("No measurement alias for encoding path: %s", path)
-				c.warned[path] = struct{}{}
+			if _, haveWarned := c.warned[encodingPath]; !haveWarned {
+				c.Log.Debugf("No measurement alias for encoding path: %s", encodingPath)
+				c.warned[encodingPath] = struct{}{}
 			}
 			c.mutex.Unlock()
 		}
 
-		if val := c.nxosValueXform(field, value, path); val != nil {
+		if val := c.nxosValueXform(field, value, encodingPath); val != nil {
 			grouper.Add(measurement, tags, timestamp, name, val)
 		} else {
 			grouper.Add(measurement, tags, timestamp, name, value)
@@ -554,8 +556,8 @@ func (c *CiscoTelemetryMDT) parseContentField(grouper *metric.SeriesGrouper, fie
 	}
 
 	var nxAttributes, nxChildren, nxRows *telemetry.TelemetryField
-	isNXOS := !strings.ContainsRune(path, ':') // IOS-XR and IOS-XE have a colon in their encoding path, NX-OS does not
-	isEVENT := isNXOS && strings.Contains(path, "EVENT-LIST")
+	isNXOS := !strings.ContainsRune(encodingPath, ':') // IOS-XR and IOS-XE have a colon in their encoding path, NX-OS does not
+	isEVENT := isNXOS && strings.Contains(encodingPath, "EVENT-LIST")
 	nxChildren = nil
 	nxAttributes = nil
 	for _, subfield := range field.Fields {
@@ -574,13 +576,13 @@ func (c *CiscoTelemetryMDT) parseContentField(grouper *metric.SeriesGrouper, fie
 			if nxAttributes == nil {
 				//call function walking over walking list.
 				for _, sub := range subfield.Fields {
-					c.parseClassAttributeField(grouper, sub, name, path, tags, timestamp)
+					c.parseClassAttributeField(grouper, sub, encodingPath, tags, timestamp)
 				}
 			}
 		} else if isNXOS && strings.HasPrefix(subfield.Name, "ROW_") {
 			nxRows = subfield
 		} else if _, isExtraTag := extraTags[subfield.Name]; !isExtraTag { // Regular telemetry decoding
-			c.parseContentField(grouper, subfield, name, path, tags, timestamp)
+			c.parseContentField(grouper, subfield, name, encodingPath, tags, timestamp)
 		}
 	}
 
@@ -595,10 +597,10 @@ func (c *CiscoTelemetryMDT) parseContentField(grouper *metric.SeriesGrouper, fie
 					//We can have subfield so recursively handle it.
 					if len(row.Fields) == 1 {
 						tags["row_number"] = strconv.FormatInt(int64(i), 10)
-						c.parseContentField(grouper, subfield, "", path, tags, timestamp)
+						c.parseContentField(grouper, subfield, "", encodingPath, tags, timestamp)
 					}
 				} else {
-					c.parseContentField(grouper, subfield, "", path, tags, timestamp)
+					c.parseContentField(grouper, subfield, "", encodingPath, tags, timestamp)
 				}
 				// Nxapi we can't identify keys always from prefix
 				tags["row_number"] = strconv.FormatInt(int64(i), 10)
@@ -629,14 +631,14 @@ func (c *CiscoTelemetryMDT) parseContentField(grouper *metric.SeriesGrouper, fie
 
 	for _, subfield := range nxAttributes.Fields {
 		if subfield.Name != "rn" {
-			c.parseContentField(grouper, subfield, "", path, tags, timestamp)
+			c.parseContentField(grouper, subfield, "", encodingPath, tags, timestamp)
 		}
 	}
 
 	if nxChildren != nil {
 		// This is a nested structure, children will inherit relative name keys of parent
 		for _, subfield := range nxChildren.Fields {
-			c.parseContentField(grouper, subfield, prefix, path, tags, timestamp)
+			c.parseContentField(grouper, subfield, prefix, encodingPath, tags, timestamp)
 		}
 	}
 	delete(tags, prefix)

plugins/inputs/cisco_telemetry_mdt/cisco_telemetry_util.go

@@ -39,7 +39,7 @@ func nxosValueXformUint64Toint64(field *telemetry.TelemetryField, value interfac
 }
 
 //xform string to float
-func nxosValueXformStringTofloat(field *telemetry.TelemetryField, value interface{}) interface{} {
+func nxosValueXformStringTofloat(field *telemetry.TelemetryField, _ interface{}) interface{} {
 	//convert property to float from string.
 	vals := field.GetStringValue()
 	if vals != "" {
@@ -51,7 +51,7 @@ func nxosValueXformStringTofloat(field *telemetry.TelemetryField, value interfac
 }
 
 //xform string to uint64
-func nxosValueXformStringToUint64(field *telemetry.TelemetryField, value interface{}) interface{} {
+func nxosValueXformStringToUint64(field *telemetry.TelemetryField, _ interface{}) interface{} {
 	//string to uint64
 	vals := field.GetStringValue()
 	if vals != "" {
@@ -63,7 +63,7 @@ func nxosValueXformStringToUint64(field *telemetry.TelemetryField, value interfa
 }
 
 //xform string to int64
-func nxosValueXformStringToInt64(field *telemetry.TelemetryField, value interface{}) interface{} {
+func nxosValueXformStringToInt64(field *telemetry.TelemetryField, _ interface{}) interface{} {
 	//string to int64
 	vals := field.GetStringValue()
 	if vals != "" {
@@ -74,26 +74,8 @@ func nxosValueXformStringToInt64(field *telemetry.TelemetryField, value interfac
 	return nil
 }
 
-//auto-xform
-func nxosValueAutoXform(field *telemetry.TelemetryField, value interface{}) interface{} {
-	//check if we want auto xformation
-	vals := field.GetStringValue()
-	if vals != "" {
-		if val64, err := strconv.ParseUint(vals, 10, 64); err == nil {
-			return val64
-		}
-		if valf, err := strconv.ParseFloat(vals, 64); err == nil {
-			return valf
-		}
-		if val64, err := strconv.ParseInt(vals, 10, 64); err == nil {
-			return val64
-		}
-	} // switch
-	return nil
-}
-
 //auto-xform float properties
-func nxosValueAutoXformFloatProp(field *telemetry.TelemetryField, value interface{}) interface{} {
+func nxosValueAutoXformFloatProp(field *telemetry.TelemetryField, _ interface{}) interface{} {
 	//check if we want auto xformation
 	vals := field.GetStringValue()
 	if vals != "" {
@@ -105,7 +87,7 @@ func nxosValueAutoXformFloatProp(field *telemetry.TelemetryField, value interfac
 }
 
 //xform uint64 to string
-func nxosValueXformUint64ToString(field *telemetry.TelemetryField, value interface{}) interface{} {
+func nxosValueXformUint64ToString(field *telemetry.TelemetryField, _ interface{}) interface{} {
 	switch val := field.ValueByType.(type) {
 	case *telemetry.TelemetryField_StringValue:
 		if len(val.StringValue) > 0 {

plugins/inputs/clickhouse/clickhouse_test.go

@@ -548,7 +548,7 @@ func TestOfflineServer(t *testing.T) {
 	assert.GreaterOrEqual(t, len(allMeasurements), len(acc.Errors))
 }
 
-func TestAutoDiscovery(t *testing.T) {
+func TestAutoDiscovery(_ *testing.T) {
 	var (
 		ts = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			type result struct {

plugins/inputs/cloud_pubsub/pubsub.go

@@ -67,7 +67,7 @@ func (ps *PubSub) SampleConfig() string {
 }
 
 // Gather does nothing for this service input.
-func (ps *PubSub) Gather(acc telegraf.Accumulator) error {
+func (ps *PubSub) Gather(_ telegraf.Accumulator) error {
 	return nil
 }
 

plugins/inputs/cloud_pubsub/pubsub_test.go

@@ -207,7 +207,7 @@ func TestRunErrorInSubscriber(t *testing.T) {
 		messages: make(chan *testMsg, 100),
 	}
 	fakeErrStr := "a fake error"
-	sub.receiver = testMessagesError(sub, errors.New("a fake error"))
+	sub.receiver = testMessagesError(errors.New("a fake error"))
 
 	ps := &PubSub{
 		Log:                      testutil.Logger{},

plugins/inputs/cloud_pubsub/subscription_stub.go

@@ -22,7 +22,7 @@ func (s *stubSub) Receive(ctx context.Context, f func(context.Context, message))
 
 type receiveFunc func(ctx context.Context, f func(context.Context, message)) error
 
-func testMessagesError(s *stubSub, expectedErr error) receiveFunc {
+func testMessagesError(expectedErr error) receiveFunc {
 	return func(ctx context.Context, f func(context.Context, message)) error {
 		return expectedErr
 	}

plugins/inputs/cloud_pubsub_push/pubsub_push.go

@@ -6,7 +6,6 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"io/ioutil"
-	"net"
 	"net/http"
 	"sync"
 	"time"
@@ -39,13 +38,12 @@ type PubSubPush struct {
 	tlsint.ServerConfig
 	parsers.Parser
 
-	listener net.Listener
-	server   *http.Server
-	acc      telegraf.TrackingAccumulator
-	ctx      context.Context
-	cancel   context.CancelFunc
-	wg       *sync.WaitGroup
-	mu       *sync.Mutex
+	server *http.Server
+	acc    telegraf.TrackingAccumulator
+	ctx    context.Context
+	cancel context.CancelFunc
+	wg     *sync.WaitGroup
+	mu     *sync.Mutex
 
 	undelivered map[telegraf.TrackingID]chan bool
 	sem         chan struct{}

plugins/inputs/cloud_pubsub_push/pubsub_push_test.go

@@ -144,7 +144,7 @@ func TestServeHTTP(t *testing.T) {
 		pubPush.SetParser(p)
 
 		dst := make(chan telegraf.Metric, 1)
-		ro := models.NewRunningOutput("test", &testOutput{failWrite: test.fail}, &models.OutputConfig{}, 1, 1)
+		ro := models.NewRunningOutput(&testOutput{failWrite: test.fail}, &models.OutputConfig{}, 1, 1)
 		pubPush.acc = agent.NewAccumulator(&testMetricMaker{}, dst).WithTracking(1)
 
 		wg.Add(1)
@@ -154,13 +154,13 @@ func TestServeHTTP(t *testing.T) {
 		}()
 
 		wg.Add(1)
-		go func(status int, d chan telegraf.Metric) {
+		go func(d chan telegraf.Metric) {
 			defer wg.Done()
 			for m := range d {
 				ro.AddMetric(m)
 				ro.Write()
 			}
-		}(test.status, dst)
+		}(dst)
 
 		ctx, cancel := context.WithTimeout(req.Context(), pubPush.WriteTimeout.Duration)
 		req = req.WithContext(ctx)
@@ -218,7 +218,7 @@ func (*testOutput) SampleConfig() string {
 	return ""
 }
 
-func (t *testOutput) Write(metrics []telegraf.Metric) error {
+func (t *testOutput) Write(_ []telegraf.Metric) error {
 	if t.failWrite {
 		return fmt.Errorf("failed write")
 	}

plugins/inputs/cloudwatch/cloudwatch.go

@@ -208,11 +208,7 @@ func (c *CloudWatch) Gather(acc telegraf.Accumulator) error {
 	c.updateWindow(time.Now())
 
 	// Get all of the possible queries so we can send groups of 100.
-	queries, err := c.getDataQueries(filteredMetrics)
-	if err != nil {
-		return err
-	}
-
+	queries := c.getDataQueries(filteredMetrics)
 	if len(queries) == 0 {
 		return nil
 	}
@@ -441,9 +437,9 @@ func (c *CloudWatch) updateWindow(relativeTo time.Time) {
 }
 
 // getDataQueries gets all of the possible queries so we can maximize the request payload.
-func (c *CloudWatch) getDataQueries(filteredMetrics []filteredMetric) ([]*cloudwatch.MetricDataQuery, error) {
+func (c *CloudWatch) getDataQueries(filteredMetrics []filteredMetric) []*cloudwatch.MetricDataQuery {
 	if c.metricCache != nil && c.metricCache.queries != nil && c.metricCache.isValid() {
-		return c.metricCache.queries, nil
+		return c.metricCache.queries
 	}
 
 	c.queryDimensions = map[string]*map[string]string{}
@@ -518,7 +514,7 @@ func (c *CloudWatch) getDataQueries(filteredMetrics []filteredMetric) ([]*cloudw
 
 	if len(dataQueries) == 0 {
 		c.Log.Debug("no metrics found to collect")
-		return nil, nil
+		return nil
 	}
 
 	if c.metricCache == nil {
@@ -531,7 +527,7 @@ func (c *CloudWatch) getDataQueries(filteredMetrics []filteredMetric) ([]*cloudw
 		c.metricCache.queries = dataQueries
 	}
 
-	return dataQueries, nil
+	return dataQueries
 }
 
 // gatherMetrics gets metric data from Cloudwatch.

plugins/inputs/cloudwatch/cloudwatch_test.go

@@ -135,7 +135,7 @@ func TestGather(t *testing.T) {
 
 type mockSelectMetricsCloudWatchClient struct{}
 
-func (m *mockSelectMetricsCloudWatchClient) ListMetrics(params *cloudwatch.ListMetricsInput) (*cloudwatch.ListMetricsOutput, error) {
+func (m *mockSelectMetricsCloudWatchClient) ListMetrics(_ *cloudwatch.ListMetricsInput) (*cloudwatch.ListMetricsOutput, error) {
 	metrics := []*cloudwatch.Metric{}
 	// 4 metrics are available
 	metricNames := []string{"Latency", "RequestCount", "HealthyHostCount", "UnHealthyHostCount"}
@@ -182,7 +182,7 @@ func (m *mockSelectMetricsCloudWatchClient) ListMetrics(params *cloudwatch.ListM
 	return result, nil
 }
 
-func (m *mockSelectMetricsCloudWatchClient) GetMetricData(params *cloudwatch.GetMetricDataInput) (*cloudwatch.GetMetricDataOutput, error) {
+func (m *mockSelectMetricsCloudWatchClient) GetMetricData(_ *cloudwatch.GetMetricDataInput) (*cloudwatch.GetMetricDataOutput, error) {
 	return nil, nil
 }
 
@@ -246,7 +246,7 @@ func TestGenerateStatisticsInputParams(t *testing.T) {
 	c.updateWindow(now)
 
 	statFilter, _ := filter.NewIncludeExcludeFilter(nil, nil)
-	queries, _ := c.getDataQueries([]filteredMetric{{metrics: []*cloudwatch.Metric{m}, statFilter: statFilter}})
+	queries := c.getDataQueries([]filteredMetric{{metrics: []*cloudwatch.Metric{m}, statFilter: statFilter}})
 	params := c.getDataInputs(queries)
 
 	assert.EqualValues(t, *params.EndTime, now.Add(-time.Duration(c.Delay)))
@@ -283,7 +283,7 @@ func TestGenerateStatisticsInputParamsFiltered(t *testing.T) {
 	c.updateWindow(now)
 
 	statFilter, _ := filter.NewIncludeExcludeFilter([]string{"average", "sample_count"}, nil)
-	queries, _ := c.getDataQueries([]filteredMetric{{metrics: []*cloudwatch.Metric{m}, statFilter: statFilter}})
+	queries := c.getDataQueries([]filteredMetric{{metrics: []*cloudwatch.Metric{m}, statFilter: statFilter}})
 	params := c.getDataInputs(queries)
 
 	assert.EqualValues(t, *params.EndTime, now.Add(-time.Duration(c.Delay)))

plugins/inputs/cpu/cpu_test.go

@@ -48,26 +48,22 @@ func TestCPUStats(t *testing.T) {
 
 	cs := NewCPUStats(&mps)
 
-	cputags := map[string]string{
-		"cpu": "cpu0",
-	}
-
 	err := cs.Gather(&acc)
 	require.NoError(t, err)
 
 	// Computed values are checked with delta > 0 because of floating point arithmetic
 	// imprecision
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_user", 8.8, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_system", 8.2, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_idle", 80.1, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_active", 19.9, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_nice", 1.3, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_iowait", 0.8389, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_irq", 0.6, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_softirq", 0.11, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_steal", 0.0511, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_guest", 3.1, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_guest_nice", 0.324, 0, cputags)
+	assertContainsTaggedFloat(t, &acc, "time_user", 8.8, 0)
+	assertContainsTaggedFloat(t, &acc, "time_system", 8.2, 0)
+	assertContainsTaggedFloat(t, &acc, "time_idle", 80.1, 0)
+	assertContainsTaggedFloat(t, &acc, "time_active", 19.9, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "time_nice", 1.3, 0)
+	assertContainsTaggedFloat(t, &acc, "time_iowait", 0.8389, 0)
+	assertContainsTaggedFloat(t, &acc, "time_irq", 0.6, 0)
+	assertContainsTaggedFloat(t, &acc, "time_softirq", 0.11, 0)
+	assertContainsTaggedFloat(t, &acc, "time_steal", 0.0511, 0)
+	assertContainsTaggedFloat(t, &acc, "time_guest", 3.1, 0)
+	assertContainsTaggedFloat(t, &acc, "time_guest_nice", 0.324, 0)
 
 	mps2 := system.MockPS{}
 	mps2.On("CPUTimes").Return([]cpu.TimesStat{cts2}, nil)
@@ -77,29 +73,29 @@ func TestCPUStats(t *testing.T) {
 	err = cs.Gather(&acc)
 	require.NoError(t, err)
 
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_user", 24.9, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_system", 10.9, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_idle", 157.9798, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_active", 42.0202, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_nice", 3.5, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_iowait", 0.929, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_irq", 1.2, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_softirq", 0.31, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_steal", 0.2812, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_guest", 11.4, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_guest_nice", 2.524, 0, cputags)
+	assertContainsTaggedFloat(t, &acc, "time_user", 24.9, 0)
+	assertContainsTaggedFloat(t, &acc, "time_system", 10.9, 0)
+	assertContainsTaggedFloat(t, &acc, "time_idle", 157.9798, 0)
+	assertContainsTaggedFloat(t, &acc, "time_active", 42.0202, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "time_nice", 3.5, 0)
+	assertContainsTaggedFloat(t, &acc, "time_iowait", 0.929, 0)
+	assertContainsTaggedFloat(t, &acc, "time_irq", 1.2, 0)
+	assertContainsTaggedFloat(t, &acc, "time_softirq", 0.31, 0)
+	assertContainsTaggedFloat(t, &acc, "time_steal", 0.2812, 0)
+	assertContainsTaggedFloat(t, &acc, "time_guest", 11.4, 0)
+	assertContainsTaggedFloat(t, &acc, "time_guest_nice", 2.524, 0)
 
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_user", 7.8, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_system", 2.7, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_idle", 77.8798, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_active", 22.1202, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_nice", 0, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_iowait", 0.0901, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_irq", 0.6, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_softirq", 0.2, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_steal", 0.2301, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_guest", 8.3, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_guest_nice", 2.2, 0.0005, cputags)
+	assertContainsTaggedFloat(t, &acc, "usage_user", 7.8, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_system", 2.7, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_idle", 77.8798, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_active", 22.1202, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_nice", 0, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_iowait", 0.0901, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_irq", 0.6, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_softirq", 0.2, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_steal", 0.2301, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_guest", 8.3, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_guest_nice", 2.2, 0.0005)
 }
 
 // Asserts that a given accumulator contains a measurement of type float64 with
@@ -109,24 +105,21 @@ func TestCPUStats(t *testing.T) {
 // Parameters:
 //     t *testing.T            : Testing object to use
 //     acc testutil.Accumulator: Accumulator to examine
-//     measurement string      : Name of the measurement to examine
+//     field string            : Name of field to examine
 //     expectedValue float64   : Value to search for within the measurement
 //     delta float64           : Maximum acceptable distance of an accumulated value
 //                               from the expectedValue parameter. Useful when
 //                               floating-point arithmetic imprecision makes looking
 //                               for an exact match impractical
-//     tags map[string]string  : Tag set the found measurement must have. Set to nil to
-//                               ignore the tag set.
 func assertContainsTaggedFloat(
 	t *testing.T,
 	acc *testutil.Accumulator,
-	measurement string,
 	field string,
 	expectedValue float64,
 	delta float64,
-	tags map[string]string,
 ) {
 	var actualValue float64
+	measurement := "cpu" // always cpu
 	for _, pt := range acc.Metrics {
 		if pt.Measurement == measurement {
 			for fieldname, value := range pt.Fields {
@@ -218,18 +211,14 @@ func TestCPUTimesDecrease(t *testing.T) {
 
 	cs := NewCPUStats(&mps)
 
-	cputags := map[string]string{
-		"cpu": "cpu0",
-	}
-
 	err := cs.Gather(&acc)
 	require.NoError(t, err)
 
 	// Computed values are checked with delta > 0 because of floating point arithmetic
 	// imprecision
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_user", 18, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_idle", 80, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_iowait", 2, 0, cputags)
+	assertContainsTaggedFloat(t, &acc, "time_user", 18, 0)
+	assertContainsTaggedFloat(t, &acc, "time_idle", 80, 0)
+	assertContainsTaggedFloat(t, &acc, "time_iowait", 2, 0)
 
 	mps2 := system.MockPS{}
 	mps2.On("CPUTimes").Return([]cpu.TimesStat{cts2}, nil)
@@ -246,11 +235,11 @@ func TestCPUTimesDecrease(t *testing.T) {
 	err = cs.Gather(&acc)
 	require.NoError(t, err)
 
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_user", 56, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_idle", 120, 0, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "time_iowait", 3, 0, cputags)
+	assertContainsTaggedFloat(t, &acc, "time_user", 56, 0)
+	assertContainsTaggedFloat(t, &acc, "time_idle", 120, 0)
+	assertContainsTaggedFloat(t, &acc, "time_iowait", 3, 0)
 
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_user", 18, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_idle", 80, 0.0005, cputags)
-	assertContainsTaggedFloat(t, &acc, "cpu", "usage_iowait", 2, 0.0005, cputags)
+	assertContainsTaggedFloat(t, &acc, "usage_user", 18, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_idle", 80, 0.0005)
+	assertContainsTaggedFloat(t, &acc, "usage_iowait", 2, 0.0005)
 }

plugins/inputs/dcos/client.go

@@ -92,11 +92,10 @@ type AuthToken struct {
 
 // ClusterClient is a Client that uses the cluster URL.
 type ClusterClient struct {
-	clusterURL  *url.URL
-	httpClient  *http.Client
-	credentials *Credentials
-	token       string
-	semaphore   chan struct{}
+	clusterURL *url.URL
+	httpClient *http.Client
+	token      string
+	semaphore  chan struct{}
 }
 
 type claims struct {

plugins/inputs/dcos/creds.go

@@ -47,13 +47,13 @@ func (c *ServiceAccount) IsExpired() bool {
 	return c.auth.Text != "" || c.auth.Expire.Add(relogDuration).After(time.Now())
 }
 
-func (c *TokenCreds) Token(ctx context.Context, client Client) (string, error) {
+func (c *TokenCreds) Token(_ context.Context, _ Client) (string, error) {
 	octets, err := ioutil.ReadFile(c.Path)
 	if err != nil {
-		return "", fmt.Errorf("Error reading token file %q: %s", c.Path, err)
+		return "", fmt.Errorf("error reading token file %q: %s", c.Path, err)
 	}
 	if !utf8.Valid(octets) {
-		return "", fmt.Errorf("Token file does not contain utf-8 encoded text: %s", c.Path)
+		return "", fmt.Errorf("token file does not contain utf-8 encoded text: %s", c.Path)
 	}
 	token := strings.TrimSpace(string(octets))
 	return token, nil
@@ -63,7 +63,7 @@ func (c *TokenCreds) IsExpired() bool {
 	return true
 }
 
-func (c *NullCreds) Token(ctx context.Context, client Client) (string, error) {
+func (c *NullCreds) Token(_ context.Context, _ Client) (string, error) {
 	return "", nil
 }
 

plugins/inputs/dcos/dcos.go

@@ -66,7 +66,6 @@ type DCOS struct {
 	nodeFilter      filter.Filter
 	containerFilter filter.Filter
 	appFilter       filter.Filter
-	taskNameFilter  filter.Filter
 }
 
 func (d *DCOS) Description() string {
@@ -223,7 +222,7 @@ type point struct {
 	fields map[string]interface{}
 }
 
-func (d *DCOS) createPoints(acc telegraf.Accumulator, m *Metrics) []*point {
+func (d *DCOS) createPoints(m *Metrics) []*point {
 	points := make(map[string]*point)
 	for _, dp := range m.Datapoints {
 		fieldKey := strings.Replace(dp.Name, ".", "_", -1)
@@ -288,7 +287,7 @@ func (d *DCOS) createPoints(acc telegraf.Accumulator, m *Metrics) []*point {
 func (d *DCOS) addMetrics(acc telegraf.Accumulator, cluster, mname string, m *Metrics, tagDimensions []string) {
 	tm := time.Now()
 
-	points := d.createPoints(acc, m)
+	points := d.createPoints(m)
 
 	for _, p := range points {
 		tags := make(map[string]string)

plugins/inputs/directory_monitor/directory_monitor.go

@@ -106,7 +106,7 @@ func (monitor *DirectoryMonitor) Description() string {
 	return "Ingests files in a directory and then moves them to a target directory."
 }
 
-func (monitor *DirectoryMonitor) Gather(acc telegraf.Accumulator) error {
+func (monitor *DirectoryMonitor) Gather(_ telegraf.Accumulator) error {
 	// Get all files sitting in the directory.
 	files, err := ioutil.ReadDir(monitor.Directory)
 	if err != nil {
@@ -130,7 +130,7 @@ func (monitor *DirectoryMonitor) Gather(acc telegraf.Accumulator) error {
 
 		// If file is decaying, process it.
 		if timeThresholdExceeded {
-			monitor.processFile(file, acc)
+			monitor.processFile(file)
 		}
 	}
 
@@ -149,7 +149,7 @@ func (monitor *DirectoryMonitor) Start(acc telegraf.Accumulator) error {
 	// Monitor the files channel and read what they receive.
 	monitor.waitGroup.Add(1)
 	go func() {
-		monitor.Monitor(acc)
+		monitor.Monitor()
 		monitor.waitGroup.Done()
 	}()
 
@@ -164,7 +164,7 @@ func (monitor *DirectoryMonitor) Stop() {
 	monitor.waitGroup.Wait()
 }
 
-func (monitor *DirectoryMonitor) Monitor(acc telegraf.Accumulator) {
+func (monitor *DirectoryMonitor) Monitor() {
 	for filePath := range monitor.filesToProcess {
 		if monitor.context.Err() != nil {
 			return
@@ -182,7 +182,7 @@ func (monitor *DirectoryMonitor) Monitor(acc telegraf.Accumulator) {
 	}
 }
 
-func (monitor *DirectoryMonitor) processFile(file os.FileInfo, acc telegraf.Accumulator) {
+func (monitor *DirectoryMonitor) processFile(file os.FileInfo) {
 	if file.IsDir() {
 		return
 	}

plugins/inputs/directory_monitor/directory_monitor_test.go

@@ -77,13 +77,6 @@ func TestCSVGZImport(t *testing.T) {
 	require.NoError(t, err)
 }
 
-// For JSON data.
-type event struct {
-	Name   string
-	Speed  float64
-	Length float64
-}
-
 func TestMultipleJSONFileImports(t *testing.T) {
 	acc := testutil.Accumulator{}
 	testJsonFile := "test.json"

plugins/inputs/disque/disque.go

@@ -18,8 +18,7 @@ import (
 type Disque struct {
 	Servers []string
 
-	c   net.Conn
-	buf []byte
+	c net.Conn
 }
 
 var sampleConfig = `
@@ -87,10 +86,10 @@ func (d *Disque) Gather(acc telegraf.Accumulator) error {
 			u.Path = ""
 		}
 		wg.Add(1)
-		go func(serv string) {
+		go func() {
 			defer wg.Done()
 			acc.AddError(d.gatherServer(u, acc))
-		}(serv)
+		}()
 	}
 
 	wg.Wait()

plugins/inputs/docker/docker.go

@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"net/http"
 	"regexp"
 	"strconv"
 	"strings"
@@ -57,7 +56,6 @@ type Docker struct {
 	newClient    func(string, *tls.Config) (Client, error)
 
 	client          Client
-	httpClient      *http.Client
 	engineHost      string
 	serverVersion   string
 	filtersCreated  bool
@@ -937,15 +935,6 @@ func copyTags(in map[string]string) map[string]string {
 	return out
 }
 
-func sliceContains(in string, sl []string) bool {
-	for _, str := range sl {
-		if str == in {
-			return true
-		}
-	}
-	return false
-}
-
 // Parses the human-readable size string into the amount it represents.
 func parseSize(sizeStr string) (int64, error) {
 	matches := sizeRegex.FindStringSubmatch(sizeStr)

plugins/inputs/docker/docker_test.go

@@ -99,7 +99,7 @@ var baseClient = MockClient{
 	},
 }
 
-func newClient(host string, tlsConfig *tls.Config) (Client, error) {
+func newClient(_ string, _ *tls.Config) (Client, error) {
 	return &baseClient, nil
 }
 
@@ -1127,7 +1127,6 @@ func TestHostnameFromID(t *testing.T) {
 func Test_parseContainerStatsPerDeviceAndTotal(t *testing.T) {
 	type args struct {
 		stat             *types.StatsJSON
-		acc              telegraf.Accumulator
 		tags             map[string]string
 		id               string
 		perDeviceInclude []string

plugins/inputs/docker_log/docker_log.go

@@ -64,11 +64,6 @@ var sampleConfig = `
 
 const (
 	defaultEndpoint = "unix:///var/run/docker.sock"
-
-	// Maximum bytes of a log line before it will be split, size is mirroring
-	// docker code:
-	// https://github.com/moby/moby/blob/master/daemon/logger/copier.go#L21
-	maxLineBytes = 16 * 1024
 )
 
 var (
@@ -160,18 +155,16 @@ func (d *DockerLogs) Init() error {
 	return nil
 }
 
-func (d *DockerLogs) addToContainerList(containerID string, cancel context.CancelFunc) error {
+func (d *DockerLogs) addToContainerList(containerID string, cancel context.CancelFunc) {
 	d.mu.Lock()
 	defer d.mu.Unlock()
 	d.containerList[containerID] = cancel
-	return nil
 }
 
-func (d *DockerLogs) removeFromContainerList(containerID string) error {
+func (d *DockerLogs) removeFromContainerList(containerID string) {
 	d.mu.Lock()
 	defer d.mu.Unlock()
 	delete(d.containerList, containerID)
-	return nil
 }
 
 func (d *DockerLogs) containerInContainerList(containerID string) bool {
@@ -181,13 +174,12 @@ func (d *DockerLogs) containerInContainerList(containerID string) bool {
 	return ok
 }
 
-func (d *DockerLogs) cancelTails() error {
+func (d *DockerLogs) cancelTails() {
 	d.mu.Lock()
 	defer d.mu.Unlock()
 	for _, cancel := range d.containerList {
 		cancel()
 	}
-	return nil
 }
 
 func (d *DockerLogs) matchedContainerName(names []string) string {

plugins/inputs/dovecot/dovecot.go

@@ -48,8 +48,6 @@ var validQuery = map[string]bool{
 
 func (d *Dovecot) SampleConfig() string { return sampleConfig }
 
-const defaultPort = "24242"
-
 // Reads stats from all configured servers.
 func (d *Dovecot) Gather(acc telegraf.Accumulator) error {
 	if !validQuery[d.Type] {

plugins/inputs/elasticsearch/elasticsearch.go

@@ -558,11 +558,7 @@ func (e *Elasticsearch) gatherIndicesStats(url string, acc telegraf.Accumulator)
 // gatherSortedIndicesStats gathers stats for all indices in no particular order.
 func (e *Elasticsearch) gatherIndividualIndicesStats(indices map[string]indexStat, now time.Time, acc telegraf.Accumulator) error {
 	// Sort indices into buckets based on their configured prefix, if any matches.
-	categorizedIndexNames, err := e.categorizeIndices(indices)
-	if err != nil {
-		return err
-	}
-
+	categorizedIndexNames := e.categorizeIndices(indices)
 	for _, matchingIndices := range categorizedIndexNames {
 		// Establish the number of each category of indices to use. User can configure to use only the latest 'X' amount.
 		indicesCount := len(matchingIndices)
@@ -590,7 +586,7 @@ func (e *Elasticsearch) gatherIndividualIndicesStats(indices map[string]indexSta
 	return nil
 }
 
-func (e *Elasticsearch) categorizeIndices(indices map[string]indexStat) (map[string][]string, error) {
+func (e *Elasticsearch) categorizeIndices(indices map[string]indexStat) map[string][]string {
 	categorizedIndexNames := map[string][]string{}
 
 	// If all indices are configured to be gathered, bucket them all together.
@@ -599,7 +595,7 @@ func (e *Elasticsearch) categorizeIndices(indices map[string]indexStat) (map[str
 			categorizedIndexNames["_all"] = append(categorizedIndexNames["_all"], indexName)
 		}
 
-		return categorizedIndexNames, nil
+		return categorizedIndexNames
 	}
 
 	// Bucket each returned index with its associated configured index (if any match).
@@ -617,7 +613,7 @@ func (e *Elasticsearch) categorizeIndices(indices map[string]indexStat) (map[str
 		categorizedIndexNames[match] = append(categorizedIndexNames[match], indexName)
 	}
 
-	return categorizedIndexNames, nil
+	return categorizedIndexNames
 }
 
 func (e *Elasticsearch) gatherSingleIndexStats(name string, index indexStat, now time.Time, acc telegraf.Accumulator) error {

plugins/inputs/elasticsearch/elasticsearch_test.go

@@ -33,9 +33,9 @@ type transportMock struct {
 	body       string
 }
 
-func newTransportMock(statusCode int, body string) http.RoundTripper {
+func newTransportMock(body string) http.RoundTripper {
 	return &transportMock{
-		statusCode: statusCode,
+		statusCode: http.StatusOK,
 		body:       body,
 	}
 }
@@ -77,7 +77,7 @@ func checkNodeStatsResult(t *testing.T, acc *testutil.Accumulator) {
 func TestGather(t *testing.T) {
 	es := newElasticsearchWithClient()
 	es.Servers = []string{"http://example.com:9200"}
-	es.client.Transport = newTransportMock(http.StatusOK, nodeStatsResponse)
+	es.client.Transport = newTransportMock(nodeStatsResponse)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 
@@ -94,7 +94,7 @@ func TestGatherIndividualStats(t *testing.T) {
 	es := newElasticsearchWithClient()
 	es.Servers = []string{"http://example.com:9200"}
 	es.NodeStats = []string{"jvm", "process"}
-	es.client.Transport = newTransportMock(http.StatusOK, nodeStatsResponseJVMProcess)
+	es.client.Transport = newTransportMock(nodeStatsResponseJVMProcess)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 
@@ -120,7 +120,7 @@ func TestGatherIndividualStats(t *testing.T) {
 func TestGatherNodeStats(t *testing.T) {
 	es := newElasticsearchWithClient()
 	es.Servers = []string{"http://example.com:9200"}
-	es.client.Transport = newTransportMock(http.StatusOK, nodeStatsResponse)
+	es.client.Transport = newTransportMock(nodeStatsResponse)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 
@@ -138,7 +138,7 @@ func TestGatherClusterHealthEmptyClusterHealth(t *testing.T) {
 	es.Servers = []string{"http://example.com:9200"}
 	es.ClusterHealth = true
 	es.ClusterHealthLevel = ""
-	es.client.Transport = newTransportMock(http.StatusOK, clusterHealthResponse)
+	es.client.Transport = newTransportMock(clusterHealthResponse)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 
@@ -165,7 +165,7 @@ func TestGatherClusterHealthSpecificClusterHealth(t *testing.T) {
 	es.Servers = []string{"http://example.com:9200"}
 	es.ClusterHealth = true
 	es.ClusterHealthLevel = "cluster"
-	es.client.Transport = newTransportMock(http.StatusOK, clusterHealthResponse)
+	es.client.Transport = newTransportMock(clusterHealthResponse)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 
@@ -192,7 +192,7 @@ func TestGatherClusterHealthAlsoIndicesHealth(t *testing.T) {
 	es.Servers = []string{"http://example.com:9200"}
 	es.ClusterHealth = true
 	es.ClusterHealthLevel = "indices"
-	es.client.Transport = newTransportMock(http.StatusOK, clusterHealthResponseWithIndices)
+	es.client.Transport = newTransportMock(clusterHealthResponseWithIndices)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 
@@ -223,7 +223,7 @@ func TestGatherClusterStatsMaster(t *testing.T) {
 	info := serverInfo{nodeID: "SDFsfSDFsdfFSDSDfSFDSDF", masterID: ""}
 
 	// first get catMaster
-	es.client.Transport = newTransportMock(http.StatusOK, IsMasterResult)
+	es.client.Transport = newTransportMock(IsMasterResult)
 	masterID, err := es.getCatMaster("junk")
 	require.NoError(t, err)
 	info.masterID = masterID
@@ -238,7 +238,7 @@ func TestGatherClusterStatsMaster(t *testing.T) {
 	// now get node status, which determines whether we're master
 	var acc testutil.Accumulator
 	es.Local = true
-	es.client.Transport = newTransportMock(http.StatusOK, nodeStatsResponse)
+	es.client.Transport = newTransportMock(nodeStatsResponse)
 	if err := es.gatherNodeStats("junk", &acc); err != nil {
 		t.Fatal(err)
 	}
@@ -247,7 +247,7 @@ func TestGatherClusterStatsMaster(t *testing.T) {
 	checkNodeStatsResult(t, &acc)
 
 	// now test the clusterstats method
-	es.client.Transport = newTransportMock(http.StatusOK, clusterStatsResponse)
+	es.client.Transport = newTransportMock(clusterStatsResponse)
 	require.NoError(t, es.gatherClusterStats("junk", &acc))
 
 	tags := map[string]string{
@@ -269,7 +269,7 @@ func TestGatherClusterStatsNonMaster(t *testing.T) {
 	es.serverInfo["http://example.com:9200"] = serverInfo{nodeID: "SDFsfSDFsdfFSDSDfSFDSDF", masterID: ""}
 
 	// first get catMaster
-	es.client.Transport = newTransportMock(http.StatusOK, IsNotMasterResult)
+	es.client.Transport = newTransportMock(IsNotMasterResult)
 	masterID, err := es.getCatMaster("junk")
 	require.NoError(t, err)
 
@@ -282,7 +282,7 @@ func TestGatherClusterStatsNonMaster(t *testing.T) {
 	// now get node status, which determines whether we're master
 	var acc testutil.Accumulator
 	es.Local = true
-	es.client.Transport = newTransportMock(http.StatusOK, nodeStatsResponse)
+	es.client.Transport = newTransportMock(nodeStatsResponse)
 	if err := es.gatherNodeStats("junk", &acc); err != nil {
 		t.Fatal(err)
 	}
@@ -296,7 +296,7 @@ func TestGatherClusterIndicesStats(t *testing.T) {
 	es := newElasticsearchWithClient()
 	es.IndicesInclude = []string{"_all"}
 	es.Servers = []string{"http://example.com:9200"}
-	es.client.Transport = newTransportMock(http.StatusOK, clusterIndicesResponse)
+	es.client.Transport = newTransportMock(clusterIndicesResponse)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 
@@ -315,7 +315,7 @@ func TestGatherDateStampedIndicesStats(t *testing.T) {
 	es.IndicesInclude = []string{"twitter*", "influx*", "penguins"}
 	es.NumMostRecentIndices = 2
 	es.Servers = []string{"http://example.com:9200"}
-	es.client.Transport = newTransportMock(http.StatusOK, dateStampedIndicesResponse)
+	es.client.Transport = newTransportMock(dateStampedIndicesResponse)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 	es.Init()
@@ -357,7 +357,7 @@ func TestGatherClusterIndiceShardsStats(t *testing.T) {
 	es := newElasticsearchWithClient()
 	es.IndicesLevel = "shards"
 	es.Servers = []string{"http://example.com:9200"}
-	es.client.Transport = newTransportMock(http.StatusOK, clusterIndicesShardsResponse)
+	es.client.Transport = newTransportMock(clusterIndicesShardsResponse)
 	es.serverInfo = make(map[string]serverInfo)
 	es.serverInfo["http://example.com:9200"] = defaultServerInfo()
 

plugins/inputs/eventhub_consumer/eventhub_consumer.go

@@ -207,11 +207,7 @@ func (e *EventHub) Start(acc telegraf.Accumulator) error {
 	}()
 
 	// Configure receiver options
-	receiveOpts, err := e.configureReceiver()
-	if err != nil {
-		return err
-	}
-
+	receiveOpts := e.configureReceiver()
 	partitions := e.PartitionIDs
 
 	if len(e.PartitionIDs) == 0 {
@@ -224,7 +220,7 @@ func (e *EventHub) Start(acc telegraf.Accumulator) error {
 	}
 
 	for _, partitionID := range partitions {
-		_, err = e.hub.Receive(ctx, partitionID, e.onMessage, receiveOpts...)
+		_, err := e.hub.Receive(ctx, partitionID, e.onMessage, receiveOpts...)
 		if err != nil {
 			return fmt.Errorf("creating receiver for partition %q: %v", partitionID, err)
 		}
@@ -233,7 +229,7 @@ func (e *EventHub) Start(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (e *EventHub) configureReceiver() ([]eventhub.ReceiveOption, error) {
+func (e *EventHub) configureReceiver() []eventhub.ReceiveOption {
 	receiveOpts := []eventhub.ReceiveOption{}
 
 	if e.ConsumerGroup != "" {
@@ -254,7 +250,7 @@ func (e *EventHub) configureReceiver() ([]eventhub.ReceiveOption, error) {
 		receiveOpts = append(receiveOpts, eventhub.ReceiveWithEpoch(e.Epoch))
 	}
 
-	return receiveOpts, nil
+	return receiveOpts
 }
 
 // OnMessage handles an Event.  When this function returns without error the

plugins/inputs/exec/exec_test.go

@@ -18,9 +18,6 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-// Midnight 9/22/2015
-const baseTimeSeconds = 1442905200
-
 const validJSON = `
 {
     "status": "green",
@@ -40,20 +37,6 @@ const malformedJSON = `
     "status": "green",
 `
 
-const lineProtocol = "cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1\n"
-const lineProtocolEmpty = ""
-const lineProtocolShort = "ab"
-
-const lineProtocolMulti = `
-cpu,cpu=cpu0,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
-cpu,cpu=cpu1,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
-cpu,cpu=cpu2,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
-cpu,cpu=cpu3,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
-cpu,cpu=cpu4,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
-cpu,cpu=cpu5,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
-cpu,cpu=cpu6,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
-`
-
 type CarriageReturnTest struct {
 	input  []byte
 	output []byte
@@ -91,7 +74,7 @@ func newRunnerMock(out []byte, errout []byte, err error) Runner {
 	}
 }
 
-func (r runnerMock) Run(command string, _ time.Duration) ([]byte, []byte, error) {
+func (r runnerMock) Run(_ string, _ time.Duration) ([]byte, []byte, error) {
 	return r.out, r.errout, r.err
 }
 

plugins/inputs/execd/execd_posix.go

@@ -12,7 +12,7 @@ import (
 	"github.com/influxdata/telegraf"
 )
 
-func (e *Execd) Gather(acc telegraf.Accumulator) error {
+func (e *Execd) Gather(_ telegraf.Accumulator) error {
 	if e.process == nil || e.process.Cmd == nil {
 		return nil
 	}

plugins/inputs/execd/shim/goshim.go

@@ -26,7 +26,6 @@ import (
 type empty struct{}
 
 var (
-	forever       = 100 * 365 * 24 * time.Hour
 	envVarEscaper = strings.NewReplacer(
 		`"`, `\"`,
 		`\`, `\\`,

plugins/inputs/execd/shim/shim_test.go

@@ -104,7 +104,7 @@ func (i *testInput) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (i *testInput) Start(acc telegraf.Accumulator) error {
+func (i *testInput) Start(_ telegraf.Accumulator) error {
 	return nil
 }
 
@@ -156,7 +156,7 @@ func (i *serviceInput) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (i *serviceInput) Start(acc telegraf.Accumulator) error {
+func (i *serviceInput) Start(_ telegraf.Accumulator) error {
 	return nil
 }
 

plugins/inputs/fail2ban/fail2ban_test.go

@@ -92,7 +92,7 @@ func fakeExecCommand(command string, args ...string) *exec.Cmd {
 	return cmd
 }
 
-func TestHelperProcess(t *testing.T) {
+func TestHelperProcess(_ *testing.T) {
 	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
 		return
 	}

plugins/inputs/fluentd/fluentd_test.go

@@ -96,8 +96,6 @@ const sampleJSON = `
 
 var (
 	zero           float64
-	err            error
-	pluginOutput   []pluginData
 	expectedOutput = []pluginData{
 		// 		{"object:f48698", "dummy", "input", nil, nil, nil},
 		// 		{"object:e27138", "dummy", "input", nil, nil, nil},

plugins/inputs/graylog/graylog.go

@@ -19,7 +19,6 @@ import (
 )
 
 type ResponseMetrics struct {
-	total   int
 	Metrics []Metric `json:"metrics"`
 }
 

plugins/inputs/hddtemp/hddtemp_test.go

@@ -12,7 +12,7 @@ import (
 type mockFetcher struct {
 }
 
-func (h *mockFetcher) Fetch(address string) ([]hddtemp.Disk, error) {
+func (h *mockFetcher) Fetch(_ string) ([]hddtemp.Disk, error) {
 	return []hddtemp.Disk{
 		{
 			DeviceName:  "Disk1",

plugins/inputs/http_listener_v2/http_listener_v2.go

@@ -319,11 +319,6 @@ func methodNotAllowed(res http.ResponseWriter) {
 	res.Write([]byte(`{"error":"http: method not allowed"}`))
 }
 
-func internalServerError(res http.ResponseWriter) {
-	res.Header().Set("Content-Type", "application/json")
-	res.WriteHeader(http.StatusInternalServerError)
-}
-
 func badRequest(res http.ResponseWriter) {
 	res.Header().Set("Content-Type", "application/json")
 	res.WriteHeader(http.StatusBadRequest)

plugins/inputs/http_response/http_response_test.go

@@ -912,10 +912,8 @@ type fakeClient struct {
 	err        error
 }
 
-func (f *fakeClient) Do(req *http.Request) (*http.Response, error) {
-	return &http.Response{
-		StatusCode: f.statusCode,
-	}, f.err
+func (f *fakeClient) Do(_ *http.Request) (*http.Response, error) {
+	return &http.Response{StatusCode: f.statusCode}, f.err
 }
 
 func TestNetworkErrors(t *testing.T) {

plugins/inputs/intel_powerstat/intel_powerstat_test.go

@@ -196,9 +196,9 @@ func TestAddMetricsForSingleCoreNegative(t *testing.T) {
 
 func TestAddCPUFrequencyMetric(t *testing.T) {
 	var acc testutil.Accumulator
-	cpuID := "0"
-	coreID := "2"
-	packageID := "1"
+	cpuID := "1"
+	coreID := "3"
+	packageID := "0"
 	frequency := 1200000.2
 	power, _, _, msrMock := getPowerWithMockedServices()
 	prepareCPUInfoForSingleCPU(power, cpuID, coreID, packageID)

plugins/inputs/intel_rdt/publisher.go

@@ -18,7 +18,6 @@ type Publisher struct {
 	BufferChanProcess chan processMeasurement
 	BufferChanCores   chan string
 	errChan           chan error
-	stopChan          chan bool
 }
 
 func NewPublisher(acc telegraf.Accumulator, log telegraf.Logger, shortenedMetrics bool) Publisher {

plugins/inputs/ipmi_sensor/connection_test.go

@@ -6,11 +6,6 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-type conTest struct {
-	Got  string
-	Want *Connection
-}
-
 func TestNewConnection(t *testing.T) {
 	testData := []struct {
 		addr string

plugins/inputs/ipmi_sensor/ipmi_test.go

@@ -227,7 +227,7 @@ func fakeExecCommand(command string, args ...string) *exec.Cmd {
 // For example, if you run:
 // GO_WANT_HELPER_PROCESS=1 go test -test.run=TestHelperProcess -- chrony tracking
 // it returns below mockData.
-func TestHelperProcess(t *testing.T) {
+func TestHelperProcess(_ *testing.T) {
 	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
 		return
 	}
@@ -546,7 +546,7 @@ func fakeExecCommandV2(command string, args ...string) *exec.Cmd {
 // For example, if you run:
 // GO_WANT_HELPER_PROCESS=1 go test -test.run=TestHelperProcessV2 -- chrony tracking
 // it returns below mockData.
-func TestHelperProcessV2(t *testing.T) {
+func TestHelperProcessV2(_ *testing.T) {
 	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
 		return
 	}

plugins/inputs/jenkins/jenkins.go

@@ -295,18 +295,6 @@ func (j *Jenkins) gatherJobs(acc telegraf.Accumulator) {
 	wg.Wait()
 }
 
-// wrap the tcp request with doGet
-// block tcp request if buffered channel is full
-func (j *Jenkins) doGet(tcp func() error) error {
-	j.semaphore <- struct{}{}
-	if err := tcp(); err != nil {
-		<-j.semaphore
-		return err
-	}
-	<-j.semaphore
-	return nil
-}
-
 func (j *Jenkins) getJobDetail(jr jobRequest, acc telegraf.Accumulator) error {
 	if j.MaxSubJobDepth > 0 && jr.layer == j.MaxSubJobDepth {
 		return nil
@@ -451,7 +439,6 @@ type jobRequest struct {
 	name    string
 	parents []string
 	layer   int
-	number  int64
 }
 
 func (jr jobRequest) combined() []string {

plugins/inputs/jolokia/jolokia_test.go

@@ -98,25 +98,8 @@ const validMultiValueJSON = `
   }
 ]`
 
-const validSingleValueJSON = `
-[
-  {
-    "request":{
-      "path":"used",
-      "mbean":"java.lang:type=Memory",
-      "attribute":"HeapMemoryUsage",
-      "type":"read"
-    },
-    "value":209274376,
-    "timestamp":1446129256,
-    "status":200
-  }
-]`
-
 const invalidJSON = "I don't think this is JSON"
 
-const empty = ""
-
 var Servers = []Server{{Name: "as1", Host: "127.0.0.1", Port: "8080"}}
 var HeapMetric = Metric{Name: "heap_memory_usage",
 	Mbean: "java.lang:type=Memory", Attribute: "HeapMemoryUsage"}
@@ -130,7 +113,7 @@ type jolokiaClientStub struct {
 	statusCode   int
 }
 
-func (c jolokiaClientStub) MakeRequest(req *http.Request) (*http.Response, error) {
+func (c jolokiaClientStub) MakeRequest(_ *http.Request) (*http.Response, error) {
 	resp := http.Response{}
 	resp.StatusCode = c.statusCode
 	resp.Body = ioutil.NopCloser(strings.NewReader(c.responseBody))

plugins/inputs/jolokia2/jolokia_test.go

@@ -74,7 +74,7 @@ func TestJolokia2_ScalarValues(t *testing.T) {
 		"status": 200
 	  }]`
 
-	server := setupServer(http.StatusOK, response)
+	server := setupServer(response)
 	defer server.Close()
 	plugin := setupPlugin(t, fmt.Sprintf(config, server.URL))
 
@@ -234,7 +234,7 @@ func TestJolokia2_ObjectValues(t *testing.T) {
 		"status": 200
 	  }]`
 
-	server := setupServer(http.StatusOK, response)
+	server := setupServer(response)
 	defer server.Close()
 	plugin := setupPlugin(t, fmt.Sprintf(config, server.URL))
 
@@ -322,7 +322,7 @@ func TestJolokia2_StatusCodes(t *testing.T) {
 		"status": 500
 	}]`
 
-	server := setupServer(http.StatusOK, response)
+	server := setupServer(response)
 	defer server.Close()
 	plugin := setupPlugin(t, fmt.Sprintf(config, server.URL))
 
@@ -372,7 +372,7 @@ func TestJolokia2_TagRenaming(t *testing.T) {
 		"status": 200
 	}]`
 
-	server := setupServer(http.StatusOK, response)
+	server := setupServer(response)
 	defer server.Close()
 	plugin := setupPlugin(t, fmt.Sprintf(config, server.URL))
 
@@ -465,7 +465,7 @@ func TestJolokia2_FieldRenaming(t *testing.T) {
 		"status": 200
 	}]`
 
-	server := setupServer(http.StatusOK, response)
+	server := setupServer(response)
 	defer server.Close()
 	plugin := setupPlugin(t, fmt.Sprintf(config, server.URL))
 
@@ -573,7 +573,7 @@ func TestJolokia2_MetricMbeanMatching(t *testing.T) {
 		"status": 200
 	}]`
 
-	server := setupServer(http.StatusOK, response)
+	server := setupServer(response)
 	defer server.Close()
 	plugin := setupPlugin(t, fmt.Sprintf(config, server.URL))
 
@@ -666,7 +666,7 @@ func TestJolokia2_MetricCompaction(t *testing.T) {
 		"status": 200
 	}]`
 
-	server := setupServer(http.StatusOK, response)
+	server := setupServer(response)
 	defer server.Close()
 	plugin := setupPlugin(t, fmt.Sprintf(config, server.URL))
 
@@ -727,7 +727,7 @@ func TestJolokia2_ProxyTargets(t *testing.T) {
 		"status": 200
 	}]`
 
-	server := setupServer(http.StatusOK, response)
+	server := setupServer(response)
 	defer server.Close()
 	plugin := setupPlugin(t, fmt.Sprintf(config, server.URL))
 
@@ -762,7 +762,7 @@ func TestFillFields(t *testing.T) {
 	assert.Equal(t, map[string]interface{}{}, results)
 }
 
-func setupServer(status int, resp string) *httptest.Server {
+func setupServer(resp string) *httptest.Server {
 	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
 		//body, err := ioutil.ReadAll(r.Body)

plugins/inputs/jti_openconfig_telemetry/openconfig_telemetry.go

@@ -102,7 +102,7 @@ func (m *OpenConfigTelemetry) Description() string {
 	return "Read JTI OpenConfig Telemetry from listed sensors"
 }
 
-func (m *OpenConfigTelemetry) Gather(acc telegraf.Accumulator) error {
+func (m *OpenConfigTelemetry) Gather(_ telegraf.Accumulator) error {
 	return nil
 }
 
@@ -278,9 +278,12 @@ func (m *OpenConfigTelemetry) splitSensorConfig() int {
 }
 
 // Subscribes and collects OpenConfig telemetry data from given server
-func (m *OpenConfigTelemetry) collectData(ctx context.Context,
-	grpcServer string, grpcClientConn *grpc.ClientConn,
-	acc telegraf.Accumulator) error {
+func (m *OpenConfigTelemetry) collectData(
+	ctx context.Context,
+	grpcServer string,
+	grpcClientConn *grpc.ClientConn,
+	acc telegraf.Accumulator,
+) {
 	c := telemetry.NewOpenConfigTelemetryClient(grpcClientConn)
 	for _, sensor := range m.sensorsConfig {
 		m.wg.Add(1)
@@ -342,8 +345,6 @@ func (m *OpenConfigTelemetry) collectData(ctx context.Context,
 			}
 		}(ctx, sensor)
 	}
-
-	return nil
 }
 
 func (m *OpenConfigTelemetry) Start(acc telegraf.Accumulator) error {

plugins/inputs/jti_openconfig_telemetry/openconfig_telemetry_test.go

@@ -63,19 +63,19 @@ func (s *openConfigTelemetryServer) TelemetrySubscribe(req *telemetry.Subscripti
 	return nil
 }
 
-func (s *openConfigTelemetryServer) CancelTelemetrySubscription(ctx context.Context, req *telemetry.CancelSubscriptionRequest) (*telemetry.CancelSubscriptionReply, error) {
+func (s *openConfigTelemetryServer) CancelTelemetrySubscription(_ context.Context, _ *telemetry.CancelSubscriptionRequest) (*telemetry.CancelSubscriptionReply, error) {
 	return nil, nil
 }
 
-func (s *openConfigTelemetryServer) GetTelemetrySubscriptions(ctx context.Context, req *telemetry.GetSubscriptionsRequest) (*telemetry.GetSubscriptionsReply, error) {
+func (s *openConfigTelemetryServer) GetTelemetrySubscriptions(_ context.Context, _ *telemetry.GetSubscriptionsRequest) (*telemetry.GetSubscriptionsReply, error) {
 	return nil, nil
 }
 
-func (s *openConfigTelemetryServer) GetTelemetryOperationalState(ctx context.Context, req *telemetry.GetOperationalStateRequest) (*telemetry.GetOperationalStateReply, error) {
+func (s *openConfigTelemetryServer) GetTelemetryOperationalState(_ context.Context, _ *telemetry.GetOperationalStateRequest) (*telemetry.GetOperationalStateReply, error) {
 	return nil, nil
 }
 
-func (s *openConfigTelemetryServer) GetDataEncodings(ctx context.Context, req *telemetry.DataEncodingRequest) (*telemetry.DataEncodingReply, error) {
+func (s *openConfigTelemetryServer) GetDataEncodings(_ context.Context, _ *telemetry.DataEncodingRequest) (*telemetry.DataEncodingReply, error) {
 	return nil, nil
 }
 

plugins/inputs/kafka_consumer/kafka_consumer.go

@@ -107,7 +107,6 @@ const sampleConfig = `
 
 const (
 	defaultMaxUndeliveredMessages = 1000
-	defaultMaxMessageLen          = 1000000
 	defaultConsumerGroup          = "telegraf_metrics_consumers"
 	reconnectDelay                = 5 * time.Second
 )
@@ -256,7 +255,7 @@ func (k *KafkaConsumer) Start(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (k *KafkaConsumer) Gather(acc telegraf.Accumulator) error {
+func (k *KafkaConsumer) Gather(_ telegraf.Accumulator) error {
 	return nil
 }
 
@@ -314,11 +313,11 @@ func (h *ConsumerGroupHandler) Setup(sarama.ConsumerGroupSession) error {
 }
 
 // Run processes any delivered metrics during the lifetime of the session.
-func (h *ConsumerGroupHandler) run(ctx context.Context) error {
+func (h *ConsumerGroupHandler) run(ctx context.Context) {
 	for {
 		select {
 		case <-ctx.Done():
-			return nil
+			return
 		case track := <-h.acc.Delivered():
 			h.onDelivery(track)
 		}

plugins/inputs/kafka_consumer/kafka_consumer_test.go

@@ -23,7 +23,7 @@ type FakeConsumerGroup struct {
 	errors  chan error
 }
 
-func (g *FakeConsumerGroup) Consume(ctx context.Context, topics []string, handler sarama.ConsumerGroupHandler) error {
+func (g *FakeConsumerGroup) Consume(_ context.Context, _ []string, handler sarama.ConsumerGroupHandler) error {
 	g.handler = handler
 	g.handler.Setup(nil)
 	return nil
@@ -213,15 +213,15 @@ func (s *FakeConsumerGroupSession) GenerationID() int32 {
 	panic("not implemented")
 }
 
-func (s *FakeConsumerGroupSession) MarkOffset(topic string, partition int32, offset int64, metadata string) {
+func (s *FakeConsumerGroupSession) MarkOffset(_ string, _ int32, _ int64, _ string) {
 	panic("not implemented")
 }
 
-func (s *FakeConsumerGroupSession) ResetOffset(topic string, partition int32, offset int64, metadata string) {
+func (s *FakeConsumerGroupSession) ResetOffset(_ string, _ int32, _ int64, _ string) {
 	panic("not implemented")
 }
 
-func (s *FakeConsumerGroupSession) MarkMessage(msg *sarama.ConsumerMessage, metadata string) {
+func (s *FakeConsumerGroupSession) MarkMessage(_ *sarama.ConsumerMessage, _ string) {
 }
 
 func (s *FakeConsumerGroupSession) Context() context.Context {

plugins/inputs/kafka_consumer_legacy/kafka_consumer_legacy.go

@@ -177,7 +177,7 @@ func (k *Kafka) Stop() {
 	}
 }
 
-func (k *Kafka) Gather(acc telegraf.Accumulator) error {
+func (k *Kafka) Gather(_ telegraf.Accumulator) error {
 	return nil
 }
 

plugins/inputs/kafka_consumer_legacy/kafka_consumer_legacy_integration_test.go

@@ -78,8 +78,8 @@ func TestReadsMetricsFromKafka(t *testing.T) {
 	}
 }
 
-// Waits for the metric that was sent to the kafka broker to arrive at the kafka
-// consumer
+//nolint:unused // Used in skipped tests
+// Waits for the metric that was sent to the kafka broker to arrive at the kafka consumer
 func waitForPoint(acc *testutil.Accumulator, t *testing.T) {
 	// Give the kafka container up to 2 seconds to get the point to the consumer
 	ticker := time.NewTicker(5 * time.Millisecond)

plugins/inputs/kinesis_consumer/kinesis_consumer.go

@@ -49,7 +49,6 @@ type (
 		cons   *consumer.Consumer
 		parser parsers.Parser
 		cancel context.CancelFunc
-		ctx    context.Context
 		acc    telegraf.TrackingAccumulator
 		sem    chan struct{}
 

plugins/inputs/kube_inventory/client_test.go

@@ -5,7 +5,6 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf/plugins/common/tls"
-	"k8s.io/apimachinery/pkg/util/intstr"
 )
 
 type mockHandler struct {
@@ -20,21 +19,10 @@ func toInt32Ptr(i int32) *int32 {
 	return &i
 }
 
-func toInt64Ptr(i int64) *int64 {
-	return &i
-}
-
 func toBoolPtr(b bool) *bool {
 	return &b
 }
 
-func toIntStrPtrS(s string) *intstr.IntOrString {
-	return &intstr.IntOrString{StrVal: s}
-}
-
-func toIntStrPtrI(i int32) *intstr.IntOrString {
-	return &intstr.IntOrString{IntVal: i}
-}
 func TestNewClient(t *testing.T) {
 	_, err := newClient("https://127.0.0.1:443/", "default", "abc123", time.Second, tls.ClientConfig{})
 	if err != nil {

plugins/inputs/kube_inventory/daemonset.go

@@ -15,14 +15,11 @@ func collectDaemonSets(ctx context.Context, acc telegraf.Accumulator, ki *Kubern
 		return
 	}
 	for _, d := range list.Items {
-		if err = ki.gatherDaemonSet(d, acc); err != nil {
-			acc.AddError(err)
-			return
-		}
+		ki.gatherDaemonSet(d, acc)
 	}
 }
 
-func (ki *KubernetesInventory) gatherDaemonSet(d v1.DaemonSet, acc telegraf.Accumulator) error {
+func (ki *KubernetesInventory) gatherDaemonSet(d v1.DaemonSet, acc telegraf.Accumulator) {
 	fields := map[string]interface{}{
 		"generation":               d.Generation,
 		"current_number_scheduled": d.Status.CurrentNumberScheduled,
@@ -48,6 +45,4 @@ func (ki *KubernetesInventory) gatherDaemonSet(d v1.DaemonSet, acc telegraf.Accu
 	}
 
 	acc.AddFields(daemonSetMeasurement, fields, tags)
-
-	return nil
 }

plugins/inputs/kube_inventory/daemonset_test.go

@@ -108,10 +108,7 @@ func TestDaemonSet(t *testing.T) {
 		ks.createSelectorFilters()
 		acc := new(testutil.Accumulator)
 		for _, dset := range ((v.handler.responseMap["/daemonsets/"]).(*v1.DaemonSetList)).Items {
-			err := ks.gatherDaemonSet(dset, acc)
-			if err != nil {
-				t.Errorf("Failed to gather daemonset - %s", err.Error())
-			}
+			ks.gatherDaemonSet(dset, acc)
 		}
 
 		err := acc.FirstError()
@@ -284,10 +281,7 @@ func TestDaemonSetSelectorFilter(t *testing.T) {
 		ks.createSelectorFilters()
 		acc := new(testutil.Accumulator)
 		for _, dset := range ((v.handler.responseMap["/daemonsets/"]).(*v1.DaemonSetList)).Items {
-			err := ks.gatherDaemonSet(dset, acc)
-			if err != nil {
-				t.Errorf("Failed to gather daemonset - %s", err.Error())
-			}
+			ks.gatherDaemonSet(dset, acc)
 		}
 
 		// Grab selector tags

plugins/inputs/kube_inventory/deployment.go

@@ -14,14 +14,11 @@ func collectDeployments(ctx context.Context, acc telegraf.Accumulator, ki *Kuber
 		return
 	}
 	for _, d := range list.Items {
-		if err = ki.gatherDeployment(d, acc); err != nil {
-			acc.AddError(err)
-			return
-		}
+		ki.gatherDeployment(d, acc)
 	}
 }
 
-func (ki *KubernetesInventory) gatherDeployment(d v1.Deployment, acc telegraf.Accumulator) error {
+func (ki *KubernetesInventory) gatherDeployment(d v1.Deployment, acc telegraf.Accumulator) {
 	fields := map[string]interface{}{
 		"replicas_available":   d.Status.AvailableReplicas,
 		"replicas_unavailable": d.Status.UnavailableReplicas,
@@ -38,6 +35,4 @@ func (ki *KubernetesInventory) gatherDeployment(d v1.Deployment, acc telegraf.Ac
 	}
 
 	acc.AddFields(deploymentMeasurement, fields, tags)
-
-	return nil
 }

plugins/inputs/kube_inventory/deployment_test.go

@@ -114,10 +114,7 @@ func TestDeployment(t *testing.T) {
 		ks.createSelectorFilters()
 		acc := new(testutil.Accumulator)
 		for _, deployment := range ((v.handler.responseMap["/deployments/"]).(*v1.DeploymentList)).Items {
-			err := ks.gatherDeployment(deployment, acc)
-			if err != nil {
-				t.Errorf("Failed to gather deployment - %s", err.Error())
-			}
+			ks.gatherDeployment(deployment, acc)
 		}
 
 		err := acc.FirstError()
@@ -299,10 +296,7 @@ func TestDeploymentSelectorFilter(t *testing.T) {
 		ks.createSelectorFilters()
 		acc := new(testutil.Accumulator)
 		for _, deployment := range ((v.handler.responseMap["/deployments/"]).(*v1.DeploymentList)).Items {
-			err := ks.gatherDeployment(deployment, acc)
-			if err != nil {
-				t.Errorf("Failed to gather deployment - %s", err.Error())
-			}
+			ks.gatherDeployment(deployment, acc)
 		}
 
 		// Grab selector tags

plugins/inputs/kube_inventory/statefulset.go

@@ -15,14 +15,11 @@ func collectStatefulSets(ctx context.Context, acc telegraf.Accumulator, ki *Kube
 		return
 	}
 	for _, s := range list.Items {
-		if err = ki.gatherStatefulSet(s, acc); err != nil {
-			acc.AddError(err)
-			return
-		}
+		ki.gatherStatefulSet(s, acc)
 	}
 }
 
-func (ki *KubernetesInventory) gatherStatefulSet(s v1.StatefulSet, acc telegraf.Accumulator) error {
+func (ki *KubernetesInventory) gatherStatefulSet(s v1.StatefulSet, acc telegraf.Accumulator) {
 	status := s.Status
 	fields := map[string]interface{}{
 		"created":             s.GetCreationTimestamp().UnixNano(),
@@ -45,6 +42,4 @@ func (ki *KubernetesInventory) gatherStatefulSet(s v1.StatefulSet, acc telegraf.
 	}
 
 	acc.AddFields(statefulSetMeasurement, fields, tags)
-
-	return nil
 }

plugins/inputs/kube_inventory/statefulset_test.go

@@ -102,10 +102,7 @@ func TestStatefulSet(t *testing.T) {
 		ks.createSelectorFilters()
 		acc := new(testutil.Accumulator)
 		for _, ss := range ((v.handler.responseMap["/statefulsets/"]).(*v1.StatefulSetList)).Items {
-			err := ks.gatherStatefulSet(ss, acc)
-			if err != nil {
-				t.Errorf("Failed to gather ss - %s", err.Error())
-			}
+			ks.gatherStatefulSet(ss, acc)
 		}
 
 		err := acc.FirstError()
@@ -273,10 +270,7 @@ func TestStatefulSetSelectorFilter(t *testing.T) {
 		ks.createSelectorFilters()
 		acc := new(testutil.Accumulator)
 		for _, ss := range ((v.handler.responseMap["/statefulsets/"]).(*v1.StatefulSetList)).Items {
-			err := ks.gatherStatefulSet(ss, acc)
-			if err != nil {
-				t.Errorf("Failed to gather ss - %s", err.Error())
-			}
+			ks.gatherStatefulSet(ss, acc)
 		}
 
 		// Grab selector tags

plugins/inputs/kubernetes/kubernetes.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"io/ioutil"
 	"net/http"
-	"net/url"
 	"strings"
 	"time"
 
@@ -65,7 +64,6 @@ var sampleConfig = `
 `
 
 const (
-	summaryEndpoint           = `%s/stats/summary`
 	defaultServiceAccountPath = "/run/secrets/kubernetes.io/serviceaccount/token"
 )
 
@@ -117,15 +115,6 @@ func (k *Kubernetes) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func buildURL(endpoint string, base string) (*url.URL, error) {
-	u := fmt.Sprintf(endpoint, base)
-	addr, err := url.Parse(u)
-	if err != nil {
-		return nil, fmt.Errorf("Unable to parse address '%s': %s", u, err)
-	}
-	return addr, nil
-}
-
 func (k *Kubernetes) gatherSummary(baseURL string, acc telegraf.Accumulator) error {
 	summaryMetrics := &SummaryMetrics{}
 	err := k.LoadJSON(fmt.Sprintf("%s/stats/summary", baseURL), summaryMetrics)
@@ -139,7 +128,7 @@ func (k *Kubernetes) gatherSummary(baseURL string, acc telegraf.Accumulator) err
 	}
 	buildSystemContainerMetrics(summaryMetrics, acc)
 	buildNodeMetrics(summaryMetrics, acc)
-	buildPodMetrics(baseURL, summaryMetrics, podInfos, k.labelFilter, acc)
+	buildPodMetrics(summaryMetrics, podInfos, k.labelFilter, acc)
 	return nil
 }
 
@@ -243,7 +232,7 @@ func (k *Kubernetes) LoadJSON(url string, v interface{}) error {
 	return nil
 }
 
-func buildPodMetrics(baseURL string, summaryMetrics *SummaryMetrics, podInfo []Metadata, labelFilter filter.Filter, acc telegraf.Accumulator) {
+func buildPodMetrics(summaryMetrics *SummaryMetrics, podInfo []Metadata, labelFilter filter.Filter, acc telegraf.Accumulator) {
 	for _, pod := range summaryMetrics.Pods {
 		for _, container := range pod.Containers {
 			tags := map[string]string{

plugins/inputs/lanz/lanz.go

@@ -43,7 +43,7 @@ func (l *Lanz) Description() string {
 	return "Read metrics off Arista LANZ, via socket"
 }
 
-func (l *Lanz) Gather(acc telegraf.Accumulator) error {
+func (l *Lanz) Gather(_ telegraf.Accumulator) error {
 	return nil
 }
 

plugins/inputs/logparser/logparser.go

@@ -143,7 +143,7 @@ func (l *LogParserPlugin) Init() error {
 }
 
 // Gather is the primary function to collect the metrics for the plugin
-func (l *LogParserPlugin) Gather(acc telegraf.Accumulator) error {
+func (l *LogParserPlugin) Gather(_ telegraf.Accumulator) error {
 	l.Lock()
 	defer l.Unlock()
 

plugins/inputs/lustre2/lustre2.go

@@ -54,7 +54,6 @@ type mapping struct {
 	inProc   string // What to look for at the start of a line in /proc/fs/lustre/*
 	field    uint32 // which field to extract from that line
 	reportAs string // What measurement name to use
-	tag      string // Additional tag to add for this metric
 }
 
 var wantedOstFields = []*mapping{

plugins/inputs/mesos/mesos.go

@@ -532,49 +532,6 @@ type TaskStats struct {
 	Statistics  map[string]interface{} `json:"statistics"`
 }
 
-func (m *Mesos) gatherSlaveTaskMetrics(u *url.URL, acc telegraf.Accumulator) error {
-	var metrics []TaskStats
-
-	tags := map[string]string{
-		"server": u.Hostname(),
-		"url":    urlTag(u),
-	}
-
-	resp, err := m.client.Get(withPath(u, "/monitor/statistics").String())
-
-	if err != nil {
-		return err
-	}
-
-	data, err := ioutil.ReadAll(resp.Body)
-	resp.Body.Close()
-	if err != nil {
-		return err
-	}
-
-	if err = json.Unmarshal([]byte(data), &metrics); err != nil {
-		return errors.New("Error decoding JSON response")
-	}
-
-	for _, task := range metrics {
-		tags["framework_id"] = task.FrameworkID
-
-		jf := jsonparser.JSONFlattener{}
-		err = jf.FlattenJSON("", task.Statistics)
-
-		if err != nil {
-			return err
-		}
-
-		timestamp := time.Unix(int64(jf.Fields["timestamp"].(float64)), 0)
-		jf.Fields["executor_id"] = task.ExecutorID
-
-		acc.AddFields("mesos_tasks", jf.Fields, tags, timestamp)
-	}
-
-	return nil
-}
-
 func withPath(u *url.URL, path string) *url.URL {
 	c := *u
 	c.Path = path

plugins/inputs/minecraft/client.go

@@ -25,12 +25,12 @@ type Connector interface {
 	Connect() (Connection, error)
 }
 
-func newConnector(hostname, port, password string) (*connector, error) {
+func newConnector(hostname, port, password string) *connector {
 	return &connector{
 		hostname: hostname,
 		port:     port,
 		password: password,
-	}, nil
+	}
 }
 
 type connector struct {
@@ -58,8 +58,8 @@ func (c *connector) Connect() (Connection, error) {
 	return &connection{rcon: rcon}, nil
 }
 
-func newClient(connector Connector) (*client, error) {
-	return &client{connector: connector}, nil
+func newClient(connector Connector) *client {
+	return &client{connector: connector}
 }
 
 type client struct {
@@ -90,13 +90,7 @@ func (c *client) Players() ([]string, error) {
 		return nil, err
 	}
 
-	players, err := parsePlayers(resp)
-	if err != nil {
-		c.conn = nil
-		return nil, err
-	}
-
-	return players, nil
+	return parsePlayers(resp), nil
 }
 
 func (c *client) Scores(player string) ([]Score, error) {
@@ -113,13 +107,7 @@ func (c *client) Scores(player string) ([]Score, error) {
 		return nil, err
 	}
 
-	scores, err := parseScores(resp)
-	if err != nil {
-		c.conn = nil
-		return nil, err
-	}
-
-	return scores, nil
+	return parseScores(resp), nil
 }
 
 type connection struct {
@@ -134,10 +122,10 @@ func (c *connection) Execute(command string) (string, error) {
 	return packet.Body, nil
 }
 
-func parsePlayers(input string) ([]string, error) {
+func parsePlayers(input string) []string {
 	parts := strings.SplitAfterN(input, ":", 2)
 	if len(parts) != 2 {
-		return []string{}, nil
+		return []string{}
 	}
 
 	names := strings.Split(parts[1], ",")
@@ -158,7 +146,7 @@ func parsePlayers(input string) ([]string, error) {
 		}
 		players = append(players, name)
 	}
-	return players, nil
+	return players
 }
 
 // Score is an individual tracked scoreboard stat.
@@ -167,9 +155,9 @@ type Score struct {
 	Value int64
 }
 
-func parseScores(input string) ([]Score, error) {
+func parseScores(input string) []Score {
 	if strings.Contains(input, "has no scores") {
-		return []Score{}, nil
+		return []Score{}
 	}
 
 	// Detect Minecraft <= 1.12
@@ -200,5 +188,6 @@ func parseScores(input string) ([]Score, error) {
 		}
 		scores = append(scores, score)
 	}
-	return scores, nil
+
+	return scores
 }

plugins/inputs/minecraft/client_test.go

@@ -98,9 +98,7 @@ func TestClient_Player(t *testing.T) {
 				conn: &MockConnection{commands: tt.commands},
 			}
 
-			client, err := newClient(connector)
-			require.NoError(t, err)
-
+			client := newClient(connector)
 			actual, err := client.Players()
 			require.NoError(t, err)
 
@@ -183,9 +181,7 @@ func TestClient_Scores(t *testing.T) {
 				conn: &MockConnection{commands: tt.commands},
 			}
 
-			client, err := newClient(connector)
-			require.NoError(t, err)
-
+			client := newClient(connector)
 			actual, err := client.Scores(tt.player)
 			require.NoError(t, err)
 

plugins/inputs/minecraft/minecraft.go

@@ -50,17 +50,8 @@ func (s *Minecraft) SampleConfig() string {
 
 func (s *Minecraft) Gather(acc telegraf.Accumulator) error {
 	if s.client == nil {
-		connector, err := newConnector(s.Server, s.Port, s.Password)
-		if err != nil {
-			return err
-		}
-
-		client, err := newClient(connector)
-		if err != nil {
-			return err
-		}
-
-		s.client = client
+		connector := newConnector(s.Server, s.Port, s.Password)
+		s.client = newClient(connector)
 	}
 
 	players, err := s.client.Players()

plugins/inputs/monit/monit_test.go

@@ -17,7 +17,7 @@ import (
 type transportMock struct {
 }
 
-func (t *transportMock) RoundTrip(r *http.Request) (*http.Response, error) {
+func (t *transportMock) RoundTrip(_ *http.Request) (*http.Response, error) {
 	errorString := "Get http://127.0.0.1:2812/_status?format=xml: " +
 		"read tcp 192.168.10.2:55610->127.0.0.1:2812: " +
 		"read: connection reset by peer"

plugins/inputs/mqtt_consumer/mqtt_consumer.go

@@ -248,14 +248,14 @@ func (m *MQTTConsumer) connect() error {
 	return nil
 }
 
-func (m *MQTTConsumer) onConnectionLost(c mqtt.Client, err error) {
+func (m *MQTTConsumer) onConnectionLost(_ mqtt.Client, err error) {
 	m.acc.AddError(fmt.Errorf("connection lost: %v", err))
 	m.Log.Debugf("Disconnected %v", m.Servers)
 	m.state = Disconnected
 	return
 }
 
-func (m *MQTTConsumer) recvMessage(c mqtt.Client, msg mqtt.Message) {
+func (m *MQTTConsumer) recvMessage(_ mqtt.Client, msg mqtt.Message) {
 	for {
 		select {
 		case track := <-m.acc.Delivered():
@@ -310,7 +310,7 @@ func (m *MQTTConsumer) Stop() {
 	m.cancel()
 }
 
-func (m *MQTTConsumer) Gather(acc telegraf.Accumulator) error {
+func (m *MQTTConsumer) Gather(_ telegraf.Accumulator) error {
 	if m.state == Disconnected {
 		m.state = Connecting
 		m.Log.Debugf("Connecting %v", m.Servers)

plugins/inputs/mqtt_consumer/mqtt_consumer_test.go

@@ -49,15 +49,15 @@ type FakeParser struct {
 // FakeParser satisfies parsers.Parser
 var _ parsers.Parser = &FakeParser{}
 
-func (p *FakeParser) Parse(buf []byte) ([]telegraf.Metric, error) {
+func (p *FakeParser) Parse(_ []byte) ([]telegraf.Metric, error) {
 	panic("not implemented")
 }
 
-func (p *FakeParser) ParseLine(line string) (telegraf.Metric, error) {
+func (p *FakeParser) ParseLine(_ string) (telegraf.Metric, error) {
 	panic("not implemented")
 }
 
-func (p *FakeParser) SetDefaultTags(tags map[string]string) {
+func (p *FakeParser) SetDefaultTags(_ map[string]string) {
 	panic("not implemented")
 }
 

plugins/inputs/nats_consumer/nats_consumer.go

@@ -264,7 +264,7 @@ func (n *natsConsumer) Stop() {
 	n.clean()
 }
 
-func (n *natsConsumer) Gather(acc telegraf.Accumulator) error {
+func (n *natsConsumer) Gather(_ telegraf.Accumulator) error {
 	return nil
 }
 

plugins/inputs/net_response/net_response_test.go

@@ -125,7 +125,7 @@ func TestTCPOK1(t *testing.T) {
 	}
 	// Start TCP server
 	wg.Add(1)
-	go TCPServer(t, &wg)
+	go TCPServer(&wg)
 	wg.Wait()
 	// Connect
 	wg.Add(1)
@@ -169,7 +169,7 @@ func TestTCPOK2(t *testing.T) {
 	}
 	// Start TCP server
 	wg.Add(1)
-	go TCPServer(t, &wg)
+	go TCPServer(&wg)
 	wg.Wait()
 	// Connect
 	wg.Add(1)
@@ -247,7 +247,7 @@ func TestUDPOK1(t *testing.T) {
 	}
 	// Start UDP server
 	wg.Add(1)
-	go UDPServer(t, &wg)
+	go UDPServer(&wg)
 	wg.Wait()
 	// Connect
 	wg.Add(1)
@@ -277,7 +277,7 @@ func TestUDPOK1(t *testing.T) {
 	wg.Wait()
 }
 
-func UDPServer(t *testing.T, wg *sync.WaitGroup) {
+func UDPServer(wg *sync.WaitGroup) {
 	udpAddr, _ := net.ResolveUDPAddr("udp", "127.0.0.1:2004")
 	conn, _ := net.ListenUDP("udp", udpAddr)
 	wg.Done()
@@ -288,7 +288,7 @@ func UDPServer(t *testing.T, wg *sync.WaitGroup) {
 	wg.Done()
 }
 
-func TCPServer(t *testing.T, wg *sync.WaitGroup) {
+func TCPServer(wg *sync.WaitGroup) {
 	tcpAddr, _ := net.ResolveTCPAddr("tcp", "127.0.0.1:2004")
 	tcpServer, _ := net.ListenTCP("tcp", tcpAddr)
 	wg.Done()

plugins/inputs/nfsclient/nfsclient.go

@@ -93,13 +93,13 @@ func convertToInt64(line []string) []int64 {
 	return nline
 }
 
-func (n *NFSClient) parseStat(mountpoint string, export string, version string, line []string, fullstat bool, acc telegraf.Accumulator) error {
+func (n *NFSClient) parseStat(mountpoint string, export string, version string, line []string, acc telegraf.Accumulator) {
 	tags := map[string]string{"mountpoint": mountpoint, "serverexport": export}
 	nline := convertToInt64(line)
 
 	if len(nline) == 0 {
 		n.Log.Warnf("Parsing Stat line with one field: %s\n", line)
-		return nil
+		return
 	}
 
 	first := strings.Replace(line[0], ":", "", 1)
@@ -191,7 +191,7 @@ func (n *NFSClient) parseStat(mountpoint string, export string, version string,
 		acc.AddFields("nfsstat", fields, tags)
 	}
 
-	if fullstat {
+	if n.Fullstat {
 		switch first {
 		case "events":
 			if len(nline) >= len(eventsFields) {
@@ -240,11 +240,9 @@ func (n *NFSClient) parseStat(mountpoint string, export string, version string,
 			}
 		}
 	}
-
-	return nil
 }
 
-func (n *NFSClient) processText(scanner *bufio.Scanner, acc telegraf.Accumulator) error {
+func (n *NFSClient) processText(scanner *bufio.Scanner, acc telegraf.Accumulator) {
 	var mount string
 	var version string
 	var export string
@@ -252,10 +250,9 @@ func (n *NFSClient) processText(scanner *bufio.Scanner, acc telegraf.Accumulator
 
 	for scanner.Scan() {
 		line := strings.Fields(scanner.Text())
+		lineLength := len(line)
 
-		line_len := len(line)
-
-		if line_len == 0 {
+		if lineLength == 0 {
 			continue
 		}
 
@@ -263,10 +260,10 @@ func (n *NFSClient) processText(scanner *bufio.Scanner, acc telegraf.Accumulator
 
 		// This denotes a new mount has been found, so set
 		// mount and export, and stop skipping (for now)
-		if line_len > 4 && choice.Contains("fstype", line) && (choice.Contains("nfs", line) || choice.Contains("nfs4", line)) {
+		if lineLength > 4 && choice.Contains("fstype", line) && (choice.Contains("nfs", line) || choice.Contains("nfs4", line)) {
 			mount = line[4]
 			export = line[1]
-		} else if line_len > 5 && (choice.Contains("(nfs)", line) || choice.Contains("(nfs4)", line)) {
+		} else if lineLength > 5 && (choice.Contains("(nfs)", line) || choice.Contains("(nfs4)", line)) {
 			version = strings.Split(line[5], "/")[1]
 		}
 
@@ -296,10 +293,9 @@ func (n *NFSClient) processText(scanner *bufio.Scanner, acc telegraf.Accumulator
 		}
 
 		if !skip {
-			n.parseStat(mount, export, version, line, n.Fullstat, acc)
+			n.parseStat(mount, export, version, line, acc)
 		}
 	}
-	return nil
 }
 
 func (n *NFSClient) getMountStatsPath() string {

plugins/inputs/nfsclient/nfsclient_test.go

@@ -20,11 +20,11 @@ func getMountStatsPath() string {
 func TestNFSClientParsev3(t *testing.T) {
 	var acc testutil.Accumulator
 
-	nfsclient := NFSClient{}
+	nfsclient := NFSClient{Fullstat: true}
 	nfsclient.nfs3Ops = map[string]bool{"READLINK": true, "GETATTR": false}
 	nfsclient.nfs4Ops = map[string]bool{"READLINK": true, "GETATTR": false}
 	data := strings.Fields("         READLINK: 500 501 502 503 504 505 506 507")
-	nfsclient.parseStat("1.2.3.4:/storage/NFS", "/A", "3", data, true, &acc)
+	nfsclient.parseStat("1.2.3.4:/storage/NFS", "/A", "3", data, &acc)
 
 	fields_ops := map[string]interface{}{
 		"ops":           int64(500),
@@ -42,11 +42,11 @@ func TestNFSClientParsev3(t *testing.T) {
 func TestNFSClientParsev4(t *testing.T) {
 	var acc testutil.Accumulator
 
-	nfsclient := NFSClient{}
+	nfsclient := NFSClient{Fullstat: true}
 	nfsclient.nfs3Ops = map[string]bool{"DESTROY_SESSION": true, "GETATTR": false}
 	nfsclient.nfs4Ops = map[string]bool{"DESTROY_SESSION": true, "GETATTR": false}
 	data := strings.Fields("    DESTROY_SESSION: 500 501 502 503 504 505 506 507")
-	nfsclient.parseStat("2.2.2.2:/nfsdata/", "/B", "4", data, true, &acc)
+	nfsclient.parseStat("2.2.2.2:/nfsdata/", "/B", "4", data, &acc)
 
 	fields_ops := map[string]interface{}{
 		"ops":           int64(500),

plugins/inputs/nginx_plus_api/nginx_plus_api_metrics_test.go

@@ -520,7 +520,7 @@ const streamServerZonesPayload = `
 `
 
 func TestGatherProcessesMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, processesPath, defaultAPIVersion, processesPayload)
+	ts, n := prepareEndpoint(t, processesPath, processesPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -541,7 +541,7 @@ func TestGatherProcessesMetrics(t *testing.T) {
 }
 
 func TestGatherConnectionsMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, connectionsPath, defaultAPIVersion, connectionsPayload)
+	ts, n := prepareEndpoint(t, connectionsPath, connectionsPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -565,7 +565,7 @@ func TestGatherConnectionsMetrics(t *testing.T) {
 }
 
 func TestGatherSslMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, sslPath, defaultAPIVersion, sslPayload)
+	ts, n := prepareEndpoint(t, sslPath, sslPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -588,7 +588,7 @@ func TestGatherSslMetrics(t *testing.T) {
 }
 
 func TestGatherHttpRequestsMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, httpRequestsPath, defaultAPIVersion, httpRequestsPayload)
+	ts, n := prepareEndpoint(t, httpRequestsPath, httpRequestsPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -610,7 +610,7 @@ func TestGatherHttpRequestsMetrics(t *testing.T) {
 }
 
 func TestGatherHttpServerZonesMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, httpServerZonesPath, defaultAPIVersion, httpServerZonesPayload)
+	ts, n := prepareEndpoint(t, httpServerZonesPath, httpServerZonesPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -664,7 +664,7 @@ func TestGatherHttpServerZonesMetrics(t *testing.T) {
 }
 
 func TestGatherHttpLocationZonesMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, httpLocationZonesPath, defaultAPIVersion, httpLocationZonesPayload)
+	ts, n := prepareEndpoint(t, httpLocationZonesPath, httpLocationZonesPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -716,7 +716,7 @@ func TestGatherHttpLocationZonesMetrics(t *testing.T) {
 }
 
 func TestGatherHttpUpstreamsMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, httpUpstreamsPath, defaultAPIVersion, httpUpstreamsPayload)
+	ts, n := prepareEndpoint(t, httpUpstreamsPath, httpUpstreamsPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -888,7 +888,7 @@ func TestGatherHttpUpstreamsMetrics(t *testing.T) {
 }
 
 func TestGatherHttpCachesMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, httpCachesPath, defaultAPIVersion, httpCachesPayload)
+	ts, n := prepareEndpoint(t, httpCachesPath, httpCachesPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -966,7 +966,7 @@ func TestGatherHttpCachesMetrics(t *testing.T) {
 }
 
 func TestGatherResolverZonesMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, resolverZonesPath, defaultAPIVersion, resolverZonesPayload)
+	ts, n := prepareEndpoint(t, resolverZonesPath, resolverZonesPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -1020,7 +1020,7 @@ func TestGatherResolverZonesMetrics(t *testing.T) {
 }
 
 func TestGatherStreamUpstreams(t *testing.T) {
-	ts, n := prepareEndpoint(t, streamUpstreamsPath, defaultAPIVersion, streamUpstreamsPayload)
+	ts, n := prepareEndpoint(t, streamUpstreamsPath, streamUpstreamsPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -1162,7 +1162,7 @@ func TestGatherStreamUpstreams(t *testing.T) {
 }
 
 func TestGatherStreamServerZonesMetrics(t *testing.T) {
-	ts, n := prepareEndpoint(t, streamServerZonesPath, defaultAPIVersion, streamServerZonesPayload)
+	ts, n := prepareEndpoint(t, streamServerZonesPath, streamServerZonesPayload)
 	defer ts.Close()
 
 	var acc testutil.Accumulator
@@ -1305,11 +1305,11 @@ func prepareAddr(t *testing.T, ts *httptest.Server) (*url.URL, string, string) {
 	return addr, host, port
 }
 
-func prepareEndpoint(t *testing.T, path string, apiVersion int64, payload string) (*httptest.Server, *NginxPlusAPI) {
+func prepareEndpoint(t *testing.T, path string, payload string) (*httptest.Server, *NginxPlusAPI) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		var rsp string
 
-		if r.URL.Path == fmt.Sprintf("/api/%d/%s", apiVersion, path) {
+		if r.URL.Path == fmt.Sprintf("/api/%d/%s", defaultAPIVersion, path) {
 			rsp = payload
 			w.Header()["Content-Type"] = []string{"application/json"}
 		} else {
@@ -1321,7 +1321,7 @@ func prepareEndpoint(t *testing.T, path string, apiVersion int64, payload string
 
 	n := &NginxPlusAPI{
 		Urls:       []string{fmt.Sprintf("%s/api", ts.URL)},
-		APIVersion: apiVersion,
+		APIVersion: defaultAPIVersion,
 	}
 
 	client, err := n.createHTTPClient()

plugins/inputs/nsd/nsd.go

@@ -11,7 +11,6 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf"
-	"github.com/influxdata/telegraf/filter"
 	"github.com/influxdata/telegraf/internal"
 	"github.com/influxdata/telegraf/plugins/inputs"
 )
@@ -26,8 +25,7 @@ type NSD struct {
 	Server     string
 	ConfigFile string
 
-	filter filter.Filter
-	run    runner
+	run runner
 }
 
 var defaultBinary = "/usr/sbin/nsd-control"

plugins/inputs/nsd/nsd_test.go

@@ -3,16 +3,14 @@ package nsd
 import (
 	"bytes"
 	"testing"
-	"time"
+
+	"github.com/stretchr/testify/assert"
 
 	"github.com/influxdata/telegraf/internal"
 	"github.com/influxdata/telegraf/testutil"
-	"github.com/stretchr/testify/assert"
 )
 
-var TestTimeout = internal.Duration{Duration: time.Second}
-
-func NSDControl(output string, Timeout internal.Duration, useSudo bool, Server string, ConfigFile string) func(string, internal.Duration, bool, string, string) (*bytes.Buffer, error) {
+func NSDControl(output string) func(string, internal.Duration, bool, string, string) (*bytes.Buffer, error) {
 	return func(string, internal.Duration, bool, string, string) (*bytes.Buffer, error) {
 		return bytes.NewBuffer([]byte(output)), nil
 	}
@@ -21,7 +19,7 @@ func NSDControl(output string, Timeout internal.Duration, useSudo bool, Server s
 func TestParseFullOutput(t *testing.T) {
 	acc := &testutil.Accumulator{}
 	v := &NSD{
-		run: NSDControl(fullOutput, TestTimeout, true, "", ""),
+		run: NSDControl(fullOutput),
 	}
 	err := v.Gather(acc)
 

plugins/inputs/nsq_consumer/nsq_consumer.go

@@ -21,7 +21,7 @@ type logger struct {
 	log telegraf.Logger
 }
 
-func (l *logger) Output(calldepth int, s string) error {
+func (l *logger) Output(_ int, s string) error {
 	l.log.Debug(s)
 	return nil
 }
@@ -179,7 +179,7 @@ func (n *NSQConsumer) Stop() {
 }
 
 // Gather is a noop
-func (n *NSQConsumer) Gather(acc telegraf.Accumulator) error {
+func (n *NSQConsumer) Gather(_ telegraf.Accumulator) error {
 	return nil
 }