Use client generator to generate all k8s clients and add respective client-go metrics (#2668)

* Define client generator to generate all k8s clients
* Increase QPS and burst values
* Capture client-go metrics
* Support for controller runtime metrics

Signed-off-by: Sanket Sudake <sanketsudake@gmail.com>

pkg/storagesvc/archivePruner.go

@@ -26,6 +26,7 @@ import (
 	"github.com/fission/fission/pkg/crd"
 	"github.com/fission/fission/pkg/generated/clientset/versioned"
 	"github.com/fission/fission/pkg/utils"
+	"github.com/pkg/errors"
 )
 
 type ArchivePruner struct {
@@ -39,14 +40,15 @@ type ArchivePruner struct {
 const defaultPruneInterval int = 60 // in minutes
 
 func MakeArchivePruner(logger *zap.Logger, stowClient *StowClient, pruneInterval time.Duration) (*ArchivePruner, error) {
-	crdClient, _, _, _, err := crd.MakeFissionClient()
+	clientGen := crd.NewClientGenerator()
+	fissionClient, err := clientGen.GetFissionClient()
 	if err != nil {
-		return nil, err
+		return nil, errors.Wrap(err, "failed to get fission client")
 	}
 
 	return &ArchivePruner{
 		logger:        logger.Named("archive_pruner"),
-		crdClient:     crdClient,
+		crdClient:     fissionClient,
 		archiveChan:   make(chan string),
 		stowClient:    stowClient,
 		pruneInterval: pruneInterval,

pkg/storagesvc/metrics.go

@@ -2,19 +2,20 @@ package storagesvc
 
 import (
 	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/promauto"
+
+	"github.com/fission/fission/pkg/utils/metrics"
 )
 
 var (
 	functionLabels = []string{}
-	totalArchives  = promauto.NewGaugeVec(
+	totalArchives  = prometheus.NewGaugeVec(
 		prometheus.GaugeOpts{
 			Name: "fission_archives",
 			Help: "Number of archives stored",
 		},
 		functionLabels,
 	)
-	totalMemoryUsage = promauto.NewGaugeVec(
+	totalMemoryUsage = prometheus.NewGaugeVec(
 		prometheus.GaugeOpts{
 			Name: "fission_archive_memory_bytes",
 			Help: "Amount of memory consumed by archives",
@@ -22,3 +23,9 @@ var (
 		functionLabels,
 	)
 )
+
+func init() {
+	registry := metrics.Registry
+	registry.MustRegister(totalArchives)
+	registry.MustRegister(totalMemoryUsage)
+}