*: cleanup collector API 1 (#1547)

pkg/collector/mscluster_node/mscluster_node.go

@@ -1,11 +1,10 @@
 package mscluster_node
 
 import (
-	"github.com/prometheus-community/windows_exporter/pkg/types"
-	"github.com/prometheus-community/windows_exporter/pkg/wmi"
-
 	"github.com/alecthomas/kingpin/v2"
 	"github.com/go-kit/log"
+	"github.com/prometheus-community/windows_exporter/pkg/types"
+	"github.com/prometheus-community/windows_exporter/pkg/wmi"
 	"github.com/prometheus/client_golang/prometheus"
 )
 
@@ -18,8 +17,8 @@ var ConfigDefaults = Config{}
 // Variable used by mscluster_resource and mscluster_resourcegroup
 var NodeName []string
 
-// A collector is a Prometheus collector for WMI MSCluster_Node metrics
-type collector struct {
+// A Collector is a Prometheus Collector for WMI MSCluster_Node metrics
+type Collector struct {
 	logger log.Logger
 
 	BuildNumber           *prometheus.Desc
@@ -38,29 +37,34 @@ type collector struct {
 	StatusInformation     *prometheus.Desc
 }
 
-func New(logger log.Logger, _ *Config) types.Collector {
-	c := &collector{}
+func New(logger log.Logger, _ *Config) *Collector {
+	c := &Collector{}
 	c.SetLogger(logger)
+
 	return c
 }
 
-func NewWithFlags(_ *kingpin.Application) types.Collector {
-	return &collector{}
+func NewWithFlags(_ *kingpin.Application) *Collector {
+	return &Collector{}
 }
 
-func (c *collector) GetName() string {
+func (c *Collector) GetName() string {
 	return Name
 }
 
-func (c *collector) SetLogger(logger log.Logger) {
+func (c *Collector) SetLogger(logger log.Logger) {
 	c.logger = log.With(logger, "collector", Name)
 }
 
-func (c *collector) GetPerfCounter() ([]string, error) {
+func (c *Collector) GetPerfCounter() ([]string, error) {
 	return []string{"Memory"}, nil
 }
 
-func (c *collector) Build() error {
+func (c *Collector) Close() error {
+	return nil
+}
+
+func (c *Collector) Build() error {
 	c.BuildNumber = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "build_number"),
 		"Provides access to the node's BuildNumber property.",
@@ -171,7 +175,7 @@ type MSCluster_Node struct {
 
 // Collect sends the metric values for each metric
 // to the provided prometheus Metric channel.
-func (c *collector) Collect(_ *types.ScrapeContext, ch chan<- prometheus.Metric) error {
+func (c *Collector) Collect(_ *types.ScrapeContext, ch chan<- prometheus.Metric) error {
 	var dst []MSCluster_Node
 	q := wmi.QueryAll(&dst, c.logger)
 	if err := wmi.QueryNamespace(q, &dst, "root/MSCluster"); err != nil {
@@ -181,7 +185,6 @@ func (c *collector) Collect(_ *types.ScrapeContext, ch chan<- prometheus.Metric)
 	NodeName = []string{}
 
 	for _, v := range dst {
-
 		ch <- prometheus.MustNewConstMetric(
 			c.BuildNumber,
 			prometheus.GaugeValue,