internal: Making poolcache typed and merged into fscache (#2693)

Merged pool cache package into fscache to avoid import cycle.
Also changed all types in pool cache from interface to specific
types.

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

pkg/executor/fscache/poolcache_test.go

@@ -0,0 +1,72 @@
+package fscache
+
+import (
+	"context"
+	"log"
+	"testing"
+
+	"k8s.io/apimachinery/pkg/api/resource"
+
+	"github.com/fission/fission/pkg/utils/loggerfactory"
+)
+
+func checkErr(err error) {
+	if err != nil {
+		log.Panicf("err: %v", err)
+	}
+}
+
+func TestPoolCache(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	logger := loggerfactory.GetLogger()
+	c := NewPoolCache(logger)
+
+	c.SetSvcValue(ctx, "func", "ip", &FuncSvc{
+		Name: "value",
+	}, resource.MustParse("45m"))
+
+	c.SetSvcValue(ctx, "func2", "ip2", &FuncSvc{
+		Name: "value2",
+	}, resource.MustParse("50m"))
+
+	c.SetSvcValue(ctx, "func2", "ip22", &FuncSvc{
+		Name: "value22",
+	}, resource.MustParse("33m"))
+
+	checkErr(c.DeleteValue(ctx, "func2", "ip2"))
+
+	cc := c.ListAvailableValue()
+	if len(cc) != 0 {
+		log.Panicf("expected 0 available items")
+	}
+
+	c.MarkAvailable("func", "ip")
+
+	_, active, err := c.GetSvcValue(ctx, "func", 5)
+	if active != 1 {
+		log.Panicln("Expected 1 active, found", active)
+	}
+	checkErr(err)
+
+	checkErr(c.DeleteValue(ctx, "func", "ip"))
+
+	_, _, err = c.GetSvcValue(ctx, "func", 5)
+	if err == nil {
+		log.Panicf("found deleted element")
+	}
+
+	c.SetSvcValue(ctx, "cpulimit", "100", &FuncSvc{
+		Name: "value",
+	}, resource.MustParse("3m"))
+	c.SetCPUUtilization("cpulimit", "100", resource.MustParse("4m"))
+
+	_, _, err = c.GetSvcValue(ctx, "cpulimit", 5)
+
+	if err == nil {
+		log.Panicf("received pod address with higher CPU usage than limit")
+	}
+	c.SetCPUUtilization("cpulimit", "100", resource.MustParse("2m"))
+	_, _, err = c.GetSvcValue(ctx, "cpulimit", 5)
+	checkErr(err)
+}