reconciler: only read from flatfile if config is not present

This change will allow us to unit test the configuration updates without
having to create the CNI configuration files (they're unrelated to this
unit).

Signed-off-by: Miguel Duarte Barroso <[email protected]>

cmd/controlloop/controlloop.go

@@ -193,15 +193,14 @@ func newEventRecorder(broadcaster record.EventBroadcaster) record.EventRecorder
 }
 
 func determineCronExpression() string {
-	flatipam, _, err := config.GetFlatIPAM(true, &types.IPAMConfig{}, "")
-	if err != nil {
-		_ = logging.Errorf("could not get flatipam config: %v", err)
-		os.Exit(couldNotGetFlatIPAM)
-	}
-
 	// We read the expression from a file if present, otherwise we use ReconcilerCronExpression
 	fileContents, err := os.ReadFile(reconcilerCronConfiguration)
 	if err != nil {
+		flatipam, _, err := config.GetFlatIPAM(true, &types.IPAMConfig{}, "")
+		if err != nil {
+			_ = logging.Errorf("could not get flatipam config: %v", err)
+			os.Exit(couldNotGetFlatIPAM)
+		}
 		_ = logging.Errorf("could not read file: %v, using expression from flatfile: %v", err, flatipam.IPAM.ReconcilerCronExpression)
 		return flatipam.IPAM.ReconcilerCronExpression
 	}