Executor: Dump function service cache for pool manager functions (#2789)

* dump function service cache for executor
* fix lint issue
* code refactor and lint fixes

---------

Signed-off-by: Shubham Bansal <shubhambansaliimtgn@gmail.com>
Signed-off-by: Sanket Sudake <sanketsudake@gmail.com>
Co-authored-by: Sanket Sudake <sanketsudake@gmail.com>

pkg/executor/fscache/functionServiceCache.go

@@ -35,6 +35,7 @@ import (
 	"github.com/fission/fission/pkg/crd"
 	ferror "github.com/fission/fission/pkg/error"
 	"github.com/fission/fission/pkg/executor/metrics"
+	"github.com/fission/fission/pkg/executor/util"
 )
 
 type fscRequestType int
@@ -170,6 +171,27 @@ func (fsc *FunctionServiceCache) service() {
 	}
 }
 
+// DumpDebugInfo => dump function service cache data to temporary directory of executor pod.
+func (fsc *FunctionServiceCache) DumpDebugInfo(ctx context.Context) error {
+	fsc.logger.Info("dumping function service")
+
+	file, err := util.CreateDumpFile(fsc.logger)
+	if err != nil {
+		fsc.logger.Error("error while creating file/dir", zap.String("error", err.Error()))
+		return err
+	}
+	defer file.Close()
+
+	err = fsc.connFunctionCache.LogFnSvcGroup(ctx, file)
+	if err != nil {
+		fsc.logger.Error("error while logging function service group", zap.String("error", err.Error()))
+		return err
+	}
+
+	fsc.logger.Info("dumped function service")
+	return nil
+}
+
 // GetByFunction gets a function service from cache using function key.
 func (fsc *FunctionServiceCache) GetByFunction(m *metav1.ObjectMeta) (*FuncSvc, error) {
 	key := crd.CacheKey(m)