Reverted "var" for structs/maps/slices

agent/tick_test.go

@@ -110,7 +110,7 @@ func TestUnalignedTicker(t *testing.T) {
 		time.Unix(61, 0).UTC(),
 	}
 
-	var actual []time.Time
+	actual := []time.Time{}
 	for !clock.Now().After(until) {
 		select {
 		case tm := <-ticker.Elapsed():
@@ -145,7 +145,7 @@ func TestRollingTicker(t *testing.T) {
 		time.Unix(61, 0).UTC(),
 	}
 
-	var actual []time.Time
+	actual := []time.Time{}
 	for !clock.Now().After(until) {
 		select {
 		case tm := <-ticker.Elapsed():

plugins/inputs/cloudwatch/cloudwatch.go

@@ -216,7 +216,7 @@ func (c *CloudWatch) Gather(acc telegraf.Accumulator) error {
 	wg := sync.WaitGroup{}
 	rLock := sync.Mutex{}
 
-	var results []*cloudwatch.MetricDataResult
+	results := []*cloudwatch.MetricDataResult{}
 
 	// 500 is the maximum number of metric data queries a `GetMetricData` request can contain.
 	batchSize := 500
@@ -296,12 +296,12 @@ func getFilteredMetrics(c *CloudWatch) ([]filteredMetric, error) {
 		return c.metricCache.metrics, nil
 	}
 
-	var fMetrics []filteredMetric
+	fMetrics := []filteredMetric{}
 
 	// check for provided metric filter
 	if c.Metrics != nil {
 		for _, m := range c.Metrics {
-			var metrics []*cloudwatch.Metric
+			metrics := []*cloudwatch.Metric{}
 			if !hasWildcard(m.Dimensions) {
 				dimensions := make([]*cloudwatch.Dimension, len(m.Dimensions))
 				for k, d := range m.Dimensions {
@@ -374,7 +374,8 @@ func getFilteredMetrics(c *CloudWatch) ([]filteredMetric, error) {
 
 // fetchNamespaceMetrics retrieves available metrics for a given CloudWatch namespace.
 func (c *CloudWatch) fetchNamespaceMetrics() ([]*cloudwatch.Metric, error) {
-	var metrics []*cloudwatch.Metric
+	metrics := []*cloudwatch.Metric{}
+
 	var token *string
 	var params *cloudwatch.ListMetricsInput
 	var recentlyActive *string
@@ -431,7 +432,7 @@ func (c *CloudWatch) getDataQueries(filteredMetrics []filteredMetric) ([]*cloudw
 
 	c.queryDimensions = map[string]*map[string]string{}
 
-	var dataQueries []*cloudwatch.MetricDataQuery
+	dataQueries := []*cloudwatch.MetricDataQuery{}
 	for i, filtered := range filteredMetrics {
 		for j, metric := range filtered.metrics {
 			id := strconv.Itoa(j) + "_" + strconv.Itoa(i)
@@ -521,7 +522,7 @@ func (c *CloudWatch) getDataQueries(filteredMetrics []filteredMetric) ([]*cloudw
 func (c *CloudWatch) gatherMetrics(
 	params *cloudwatch.GetMetricDataInput,
 ) ([]*cloudwatch.MetricDataResult, error) {
-	var results []*cloudwatch.MetricDataResult
+	results := []*cloudwatch.MetricDataResult{}
 
 	for {
 		resp, err := c.client.GetMetricData(params)

plugins/inputs/diskio/diskio.go

@@ -93,7 +93,7 @@ func (d *DiskIO) Gather(acc telegraf.Accumulator) error {
 		}
 	}
 
-	var devices []string
+	devices := []string{}
 	if d.deviceFilter == nil {
 		devices = d.Devices
 	}

plugins/inputs/modbus/modbus.go

@@ -206,7 +206,7 @@ func (m *Modbus) InitRegister(fields []fieldContainer, name string) error {
 		return err
 	}
 
-	var addrs []uint16
+	addrs := []uint16{}
 	for _, field := range fields {
 		for _, a := range field.Address {
 			addrs = append(addrs, a)
@@ -390,7 +390,7 @@ func validateFieldContainers(t []fieldContainer, n string) error {
 
 func removeDuplicates(elements []uint16) []uint16 {
 	encountered := map[uint16]bool{}
-	var result []uint16
+	result := []uint16{}
 
 	for v := range elements {
 		if encountered[elements[v]] {

plugins/inputs/solr/solr.go

@@ -192,7 +192,7 @@ func (s *Solr) filterCores(serverCores []string) []string {
 
 // Return list of cores from solr server
 func getCoresFromStatus(adminCoresStatus *AdminCoresStatus) []string {
-	var serverCores []string
+	serverCores := []string{}
 	for coreName := range adminCoresStatus.Status {
 		serverCores = append(serverCores, coreName)
 	}

plugins/inputs/stackdriver/stackdriver.go

@@ -531,7 +531,7 @@ func (s *Stackdriver) generatetimeSeriesConfs(
 		return s.timeSeriesConfCache.TimeSeriesConfs, nil
 	}
 
-	var ret []*timeSeriesConf
+	ret := []*timeSeriesConf{}
 	req := &monitoringpb.ListMetricDescriptorsRequest{
 		Name: monitoring.MetricProjectPath(s.Project),
 	}

plugins/outputs/cloudwatch/cloudwatch_test.go

@@ -158,7 +158,7 @@ func TestPartitionDatums(t *testing.T) {
 		Value:      aws.Float64(1),
 	}
 
-	var zeroDatum []*cloudwatch.MetricDatum
+	zeroDatum := []*cloudwatch.MetricDatum{}
 	oneDatum := []*cloudwatch.MetricDatum{&testDatum}
 	twoDatum := []*cloudwatch.MetricDatum{&testDatum, &testDatum}
 	threeDatum := []*cloudwatch.MetricDatum{&testDatum, &testDatum, &testDatum}

plugins/outputs/datadog/datadog.go

@@ -65,7 +65,7 @@ func (d *Datadog) Connect() error {
 
 func (d *Datadog) Write(metrics []telegraf.Metric) error {
 	ts := TimeSeries{}
-	var tempSeries []*Metric
+	tempSeries := []*Metric{}
 	metricCounter := 0
 
 	for _, m := range metrics {

plugins/outputs/file/file.go

@@ -58,7 +58,7 @@ func (f *File) SetSerializer(serializer serializers.Serializer) {
 }
 
 func (f *File) Connect() error {
-	var writers []io.Writer
+	writers := []io.Writer{}
 
 	if len(f.Files) == 0 {
 		f.Files = []string{"stdout"}

plugins/outputs/riemann_legacy/riemann.go

@@ -92,7 +92,7 @@ func (r *Riemann) Write(metrics []telegraf.Metric) error {
 }
 
 func buildEvents(p telegraf.Metric, s string) []*raidman.Event {
-	var events []*raidman.Event
+	events := []*raidman.Event{}
 	for fieldName, value := range p.Fields() {
 		host, ok := p.Tags()["host"]
 		if !ok {
@@ -123,12 +123,12 @@ func buildEvents(p telegraf.Metric, s string) []*raidman.Event {
 }
 
 func serviceName(s string, n string, t map[string]string, f string) string {
-	var serviceStrings []string
+	serviceStrings := []string{}
 	serviceStrings = append(serviceStrings, n)
 
 	// we'll skip the 'host' tag
-	var tagStrings []string
-	var tagNames []string
+	tagStrings := []string{}
+	tagNames := []string{}
 
 	for tagName := range t {
 		tagNames = append(tagNames, tagName)

plugins/processors/topk/topk.go

@@ -276,7 +276,7 @@ func (t *TopK) push() []telegraf.Metric {
 	}
 
 	// The return value that will hold the returned metrics
-	var ret []telegraf.Metric
+	var ret = make([]telegraf.Metric, 0, 0)
 	// Get the top K metrics for each field and add them to the return value
 	addedKeys := make(map[string]bool)
 	for _, field := range t.Fields {