98 grouping with self loops (#152)

added an optimization to grouping in which self loops are treated as don't cares

pkg/ibmvpc/examples/acl_testing3_with_grouping.txt

@@ -5,9 +5,7 @@ vsi1-ky[10.240.10.4] => Public Internet 161.26.0.0/16 : protocol: UDP *
 vsi1-ky[10.240.10.4] => vsi2-ky[10.240.20.4] : protocol: TCP,UDP
 vsi2-ky[10.240.20.4] => Public Internet (all ranges) : All Connections
 vsi2-ky[10.240.20.4] => vsi1-ky[10.240.10.4] : All Connections *
-vsi3a-ky[10.240.30.5],vsi3b-ky[10.240.30.6] => vsi3c-ky[10.240.30.4] : All Connections
 vsi3a-ky[10.240.30.5],vsi3b-ky[10.240.30.6],vsi3c-ky[10.240.30.4] => vsi1-ky[10.240.10.4] : All Connections *
-vsi3a-ky[10.240.30.5],vsi3c-ky[10.240.30.4] => vsi3b-ky[10.240.30.6] : All Connections
-vsi3b-ky[10.240.30.6],vsi3c-ky[10.240.30.4] => vsi3a-ky[10.240.30.5] : All Connections
+vsi3a-ky[10.240.30.5],vsi3b-ky[10.240.30.6],vsi3c-ky[10.240.30.4] => vsi3a-ky[10.240.30.5],vsi3b-ky[10.240.30.6],vsi3c-ky[10.240.30.4] : All Connections
 
 connections are stateful unless marked with *

pkg/ibmvpc/examples/sg_testing1_new_groupingsubnetsBased_withPGW.txt

@@ -1,7 +1,5 @@
 combined connections between subnets:
 subnet1-ky => Public Internet (all ranges) : All Connections
-subnet1-ky => subnet2-ky,subnet3-ky : All Connections
-subnet2-ky => subnet1-ky,subnet3-ky : All Connections
-subnet3-ky => subnet1-ky,subnet2-ky : All Connections
+subnet1-ky,subnet2-ky,subnet3-ky => subnet1-ky,subnet2-ky,subnet3-ky : All Connections
 
 connections are stateful unless marked with *

pkg/vpcmodel/grouping.go

@@ -145,8 +145,8 @@ func (g *groupingConnections) addPublicConnectivity(ep EndpointElem, conn string
 	(*g)[ep][conn] = append((*g)[ep][conn], targetNode)
 }
 
-// vsiGroupingBySubnets returns a slice of EndpointElem objects produced from an input slice, by grouping
-// set of elements that represent network interface nodes from the same subnet into a single groupedNetworkInterfaces object
+// vsiGroupingBySubnets returns a slice of EndpointElem objects, by grouping set of elements that
+// represent network interface nodes from the same subnet into a single groupedNetworkInterfaces object
 func vsiGroupingBySubnets(groupedConnLines *GroupConnLines,
 	elemsList []EndpointElem, c *CloudConfig) []EndpointElem {
 	res := []EndpointElem{}
@@ -174,7 +174,8 @@ func vsiGroupingBySubnets(groupedConnLines *GroupConnLines,
 	return res
 }
 
-// subnetGrouping returns a slice of EndpointElem objects produced from an input slice, by grouping EndpointElem that represents a subnet
+// subnetGrouping returns a slice of EndpointElem objects produced from an input slice, by grouping
+// set of elements that represent subnets into a single groupedNetworkInterfaces object
 func subnetGrouping(groupedConnLines *GroupConnLines,
 	elemsList []EndpointElem) []EndpointElem {
 	res := []EndpointElem{}
@@ -244,6 +245,20 @@ func (g *GroupConnLines) groupExternalAddressesForSubnets() {
 	g.GroupedLines = res
 }
 
+// aux func, returns true iff the EndpointElem is Node if grouping vsis or NodeSet if grouping subnets
+func isInternalOfRequiredType(ep EndpointElem, groupVsi bool) bool {
+	if groupVsi { // groups vsis Nodes
+		if _, ok := ep.(Node); !ok {
+			return false
+		}
+	} else { // groups subnets NodeSets
+		if _, ok := ep.(NodeSet); !ok {
+			return false
+		}
+	}
+	return true
+}
+
 // groups src/targets for either Vsis or Subnets
 func (g *GroupConnLines) groupLinesByKey(srcGrouping, groupVsi bool) (res []*GroupedConnLine,
 	groupingSrcOrDst map[string][]*GroupedConnLine) {
@@ -253,24 +268,22 @@ func (g *GroupConnLines) groupLinesByKey(srcGrouping, groupVsi bool) (res []*Gro
 	// populate map groupingSrcOrDst
 	for _, line := range g.GroupedLines {
 		srcOrDst, dstOrSrc := line.getSrcOrDst(srcGrouping), line.getSrcOrDst(!srcGrouping)
-		if groupVsi { // groups vsis Nodes
-			if _, ok := srcOrDst.(Node); !ok {
-				res = append(res, line)
-				continue
-			}
-		} else { // groups subnets NodeSets
-			if _, ok := srcOrDst.(NodeSet); !ok {
-				res = append(res, line)
-				continue
-			}
+		if !isInternalOfRequiredType(srcOrDst, groupVsi) {
+			res = append(res, line)
+			continue
 		}
-		key := dstOrSrc.Name() + ";" + line.Conn
+		key := getKeyOfGroupConnLines(dstOrSrc, line.Conn)
 		if _, ok := groupingSrcOrDst[key]; !ok {
 			groupingSrcOrDst[key] = []*GroupedConnLine{}
 		}
 		groupingSrcOrDst[key] = append(groupingSrcOrDst[key], line)
 	}
-	return res, groupingSrcOrDst
+	newGroupingSrcOrDst := g.extendGroupingSelfLoops(groupingSrcOrDst, srcGrouping)
+	return res, newGroupingSrcOrDst
+}
+
+func getKeyOfGroupConnLines(ep EndpointElem, connection string) string {
+	return ep.Name() + commaSeparator + connection
 }
 
 // assuming the  g.groupedLines was already initialized by previous step groupExternalAddresses()