Modernize codebase (#3431)

Run Go modernize tool and apply fixes.

Signed-off-by: Ben Kochie <superq@gmail.com>

Author: SuperQ

collector/bonding_linux.go

@@ -78,13 +78,13 @@ func readBondingStats(root string) (status map[string][2]int, err error) {
 	if err != nil {
 		return nil, err
 	}
-	for _, master := range strings.Fields(string(masters)) {
+	for master := range strings.FieldsSeq(string(masters)) {
 		slaves, err := os.ReadFile(filepath.Join(root, master, "bonding", "slaves"))
 		if err != nil {
 			return nil, err
 		}
 		sstat := [2]int{0, 0}
-		for _, slave := range strings.Fields(string(slaves)) {
+		for slave := range strings.FieldsSeq(string(slaves)) {
 			state, err := os.ReadFile(filepath.Join(root, master, fmt.Sprintf("lower_%s", slave), "bonding_slave", "mii_status"))
 			if errors.Is(err, os.ErrNotExist) {
 				// some older? kernels use slave_ prefix

collector/collector.go

@@ -199,7 +199,7 @@ func IsNoDataError(err error) bool {
 }
 
 // pushMetric helps construct and convert a variety of value types into Prometheus float64 metrics.
-func pushMetric(ch chan<- prometheus.Metric, fieldDesc *prometheus.Desc, name string, value interface{}, valueType prometheus.ValueType, labelValues ...string) {
+func pushMetric(ch chan<- prometheus.Metric, fieldDesc *prometheus.Desc, name string, value any, valueType prometheus.ValueType, labelValues ...string) {
 	var fVal float64
 	switch val := value.(type) {
 	case uint8:

collector/cpufreq_linux.go

@@ -106,8 +106,8 @@ func (c *cpuFreqCollector) Update(ch chan<- prometheus.Metric) error {
 			)
 		}
 		if stats.Governor != "" {
-			availableGovernors := strings.Split(stats.AvailableGovernors, " ")
-			for _, g := range availableGovernors {
+			availableGovernors := strings.SplitSeq(stats.AvailableGovernors, " ")
+			for g := range availableGovernors {
 				state := 0
 				if g == stats.Governor {
 					state = 1

collector/ethtool_linux_test.go

@@ -139,7 +139,7 @@ func (e *EthtoolFixture) Stats(intf string) (map[string]uint64, error) {
 
 func readModes(modes string) uint32 {
 	var out uint32
-	for _, mode := range strings.Split(modes, " ") {
+	for mode := range strings.SplitSeq(modes, " ") {
 		switch mode {
 		case "10baseT/Half":
 			out |= (1 << unix.ETHTOOL_LINK_MODE_10baseT_Half_BIT)
@@ -162,7 +162,7 @@ func readModes(modes string) uint32 {
 
 func readPortTypes(portTypes string) uint32 {
 	var out uint32
-	for _, ptype := range strings.Split(portTypes, " ") {
+	for ptype := range strings.SplitSeq(portTypes, " ") {
 		ptype = strings.Trim(ptype, " \t")
 		if ptype == "TP" {
 			out |= (1 << unix.ETHTOOL_LINK_MODE_TP_BIT)

collector/filesystem_linux.go

@@ -58,10 +58,7 @@ func (c *filesystemCollector) GetStats() ([]filesystemStats, error) {
 	statChan := make(chan filesystemStats)
 	wg := sync.WaitGroup{}
 
-	workerCount := *statWorkerCount
-	if workerCount < 1 {
-		workerCount = 1
-	}
+	workerCount := max(*statWorkerCount, 1)
 
 	for i := 0; i < workerCount; i++ {
 		wg.Add(1)

collector/hwmon_linux.go

@@ -23,6 +23,7 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"slices"
 	"strconv"
 	"strings"
 
@@ -154,11 +155,8 @@ func collectSensorData(dir string, data map[string]map[string]string) error {
 			continue
 		}
 
-		for _, t := range hwmonSensorTypes {
-			if t == sensorType {
-				addValueFile(data, sensorType+strconv.Itoa(sensorNum), sensorProperty, filepath.Join(dir, file.Name()))
-				break
-			}
+		if slices.Contains(hwmonSensorTypes, sensorType) {
+			addValueFile(data, sensorType+strconv.Itoa(sensorNum), sensorProperty, filepath.Join(dir, file.Name()))
 		}
 	}
 	return nil

collector/logind_linux.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"log/slog"
 	"os"
+	"slices"
 	"strconv"
 
 	"github.com/godbus/dbus/v5"
@@ -138,10 +139,8 @@ func collectMetrics(ch chan<- prometheus.Metric, c logindInterface) error {
 }
 
 func knownStringOrOther(value string, known []string) string {
-	for i := range known {
-		if value == known[i] {
-			return value
-		}
+	if slices.Contains(known, value) {
+		return value
 	}
 
 	return "other"
@@ -176,19 +175,19 @@ func newDbus() (*logindDbus, error) {
 }
 
 func (c *logindDbus) listSeats() ([]string, error) {
-	var result [][]interface{}
+	var result [][]any
 	err := c.object.Call(dbusObject+".Manager.ListSeats", 0).Store(&result)
 	if err != nil {
 		return nil, err
 	}
 
-	resultInterface := make([]interface{}, len(result))
+	resultInterface := make([]any, len(result))
 	for i := range result {
 		resultInterface[i] = result[i]
 	}
 
 	seats := make([]logindSeatEntry, len(result))
-	seatsInterface := make([]interface{}, len(seats))
+	seatsInterface := make([]any, len(seats))
 	for i := range seats {
 		seatsInterface[i] = &seats[i]
 	}
@@ -209,19 +208,19 @@ func (c *logindDbus) listSeats() ([]string, error) {
 }
 
 func (c *logindDbus) listSessions() ([]logindSessionEntry, error) {
-	var result [][]interface{}
+	var result [][]any
 	err := c.object.Call(dbusObject+".Manager.ListSessions", 0).Store(&result)
 	if err != nil {
 		return nil, err
 	}
 
-	resultInterface := make([]interface{}, len(result))
+	resultInterface := make([]any, len(result))
 	for i := range result {
 		resultInterface[i] = result[i]
 	}
 
 	sessions := make([]logindSessionEntry, len(result))
-	sessionsInterface := make([]interface{}, len(sessions))
+	sessionsInterface := make([]any, len(sessions))
 	for i := range sessions {
 		sessionsInterface[i] = &sessions[i]
 	}

collector/netstat_linux.go

@@ -22,6 +22,7 @@ import (
 	"fmt"
 	"io"
 	"log/slog"
+	"maps"
 	"os"
 	"regexp"
 	"strconv"
@@ -73,12 +74,8 @@ func (c *netStatCollector) Update(ch chan<- prometheus.Metric) error {
 	}
 	// Merge the results of snmpStats into netStats (collisions are possible, but
 	// we know that the keys are always unique for the given use case).
-	for k, v := range snmpStats {
-		netStats[k] = v
-	}
-	for k, v := range snmp6Stats {
-		netStats[k] = v
-	}
+	maps.Copy(netStats, snmpStats)
+	maps.Copy(netStats, snmp6Stats)
 	for protocol, protocolStats := range netStats {
 		for name, value := range protocolStats {
 			key := protocol + "_" + name

collector/perf_linux.go

@@ -118,7 +118,7 @@ func perfTracepointFlagToTracepoints(tracepointsFlag []string) ([]*perfTracepoin
 func perfCPUFlagToCPUs(cpuFlag string) ([]int, error) {
 	var err error
 	cpus := []int{}
-	for _, subset := range strings.Split(cpuFlag, ",") {
+	for subset := range strings.SplitSeq(cpuFlag, ",") {
 		// First parse a single CPU.
 		if !strings.Contains(subset, "-") {
 			cpu, err := strconv.Atoi(subset)

collector/sysctl_linux.go

@@ -86,7 +86,7 @@ func (c *sysctlCollector) Update(ch chan<- prometheus.Metric) error {
 
 func (c *sysctlCollector) newMetrics(s *sysctl) ([]prometheus.Metric, error) {
 	var (
-		values interface{}
+		values any
 		length int
 		err    error
 	)
@@ -151,7 +151,7 @@ func (s *sysctl) metricName() string {
 	return SanitizeMetricName(s.name)
 }
 
-func (s *sysctl) newConstMetric(v interface{}) prometheus.Metric {
+func (s *sysctl) newConstMetric(v any) prometheus.Metric {
 	if s.numeric {
 		return prometheus.MustNewConstMetric(
 			prometheus.NewDesc(
@@ -171,7 +171,7 @@ func (s *sysctl) newConstMetric(v interface{}) prometheus.Metric {
 	)
 }
 
-func (s *sysctl) newIndexedMetrics(v interface{}) []prometheus.Metric {
+func (s *sysctl) newIndexedMetrics(v any) []prometheus.Metric {
 	desc := prometheus.NewDesc(
 		prometheus.BuildFQName(namespace, "sysctl", s.metricName()),
 		fmt.Sprintf("sysctl %s", s.name),
@@ -195,7 +195,7 @@ func (s *sysctl) newIndexedMetrics(v interface{}) []prometheus.Metric {
 	}
 }
 
-func (s *sysctl) newMappedMetrics(v interface{}) ([]prometheus.Metric, error) {
+func (s *sysctl) newMappedMetrics(v any) ([]prometheus.Metric, error) {
 	switch values := v.(type) {
 	case []int:
 		metrics := make([]prometheus.Metric, len(values))