OCPBUGS-64793: Infrastructure Topology calculation is wrong

If masters are schedulable then all nodes, not just non-controlplane nodes, should
be taken into account when deciding what we tell OLM operators about the topology.

Example:
1.Deploy a cluster with 3 CP nodes (schedulable) and 1 Worker Node
2.Inspect infrastructureTopology attribute of the cluster

Expect: infrastructureTopology= HighlyAvailableTopologyMode

Author: barbacbd

pkg/asset/manifests/ingress_test.go

@@ -135,15 +135,15 @@ func TestGenerateIngerssDefaultPlacement(t *testing.T) {
 			name:                      "aws single node with 0 or 1 day-1 workers",
 			installConfigBuildOptions: []icOption{icBuild.forAWS()},
 			controlPlaneTopology:      configv1.SingleReplicaTopologyMode,
-			infrastructureTopology:    configv1.SingleReplicaTopologyMode,
+			infrastructureTopology:    configv1.HighlyAvailableTopologyMode,
 			expectedIngressAWSLBType:  configv1.Classic,
 			expectedIngressPlacement:  configv1.DefaultPlacementWorkers,
 		},
 		{
 			name:                      "aws multi-node with 1 day-1 worker",
 			installConfigBuildOptions: []icOption{icBuild.forAWS()},
 			controlPlaneTopology:      configv1.HighlyAvailableTopologyMode,
-			infrastructureTopology:    configv1.SingleReplicaTopologyMode,
+			infrastructureTopology:    configv1.HighlyAvailableTopologyMode,
 			expectedIngressAWSLBType:  configv1.Classic,
 			expectedIngressPlacement:  configv1.DefaultPlacementWorkers,
 		},
@@ -187,14 +187,14 @@ func TestGenerateIngerssDefaultPlacement(t *testing.T) {
 			name:                      "none-platform single node with 0 or 1 day-1 workers",
 			installConfigBuildOptions: []icOption{icBuild.forNone()},
 			controlPlaneTopology:      configv1.SingleReplicaTopologyMode,
-			infrastructureTopology:    configv1.SingleReplicaTopologyMode,
+			infrastructureTopology:    configv1.HighlyAvailableTopologyMode,
 			expectedIngressPlacement:  configv1.DefaultPlacementControlPlane,
 		},
 		{
 			name:                      "none-platform multi-node with 1 day-1 worker",
 			installConfigBuildOptions: []icOption{icBuild.forNone()},
 			controlPlaneTopology:      configv1.HighlyAvailableTopologyMode,
-			infrastructureTopology:    configv1.SingleReplicaTopologyMode,
+			infrastructureTopology:    configv1.HighlyAvailableTopologyMode,
 			expectedIngressPlacement:  configv1.DefaultPlacementWorkers,
 		},
 		{

pkg/asset/manifests/scheduler.go

@@ -63,14 +63,9 @@ func (s *Scheduler) Generate(_ context.Context, dependencies asset.Parents) erro
 			computeReplicas += *pool.Replicas
 		}
 	}
-	if computeReplicas == 0 {
+	if computeReplicas < 2 {
 		// A schedulable host is required for a successful install to complete.
-		// If the install config has 0 replicas for compute hosts, it's one of two cases:
-		//   1. An IPI deployment with no compute hosts.  The deployment can not succeed
-		//      without MastersSchedulable = true.
-		//   2. A UPI deployment.  The deployment may add compute hosts, but to ensure the
-		//      the highest probability of a successful deployment, we default to
-		//      schedulable masters.
+		// Set the control planes to schedulable if the install config has < 2 replicas for compute hosts.
 		logrus.Warningf("Making control-plane schedulable by setting MastersSchedulable to true for Scheduler cluster settings")
 		config.Spec.MastersSchedulable = true
 	}

pkg/asset/manifests/topologies.go

@@ -28,6 +28,11 @@ func determineTopologies(installConfig *types.InstallConfig) (controlPlaneTopolo
 	for _, mp := range installConfig.Compute {
 		numOfWorkers += ptr.Deref(mp.Replicas, 0)
 	}
+	if numOfWorkers < 2 {
+		// Control planes are schedulable when there are < 2 workers.
+		// Adjust the number of schedulable nodes here to reflect.
+		numOfWorkers += controlPlaneReplicas
+	}
 
 	switch numOfWorkers {
 	case 0:

pkg/asset/manifests/topologies_test.go

@@ -66,7 +66,7 @@ func Test_DetermineTopologies(t *testing.T) {
 				},
 			},
 			expectedControlPlane: configv1.SingleReplicaTopologyMode,
-			expectedInfra:        configv1.SingleReplicaTopologyMode,
+			expectedInfra:        configv1.HighlyAvailableTopologyMode,
 		},
 		{
 			desc: "should default infra to HA and controlPlane to DualReplica for 2 control replicas",
@@ -125,6 +125,21 @@ func Test_DetermineTopologies(t *testing.T) {
 			expectedControlPlane: configv1.HighlyAvailableTopologyMode,
 			expectedInfra:        configv1.HighlyAvailableTopologyMode,
 		},
+		{
+			desc: "should set infra to HA controlPlane and compute from controlPlane value",
+			installConfig: &types.InstallConfig{
+				ControlPlane: &types.MachinePool{
+					Replicas: ptr.To[int64](3),
+				},
+				Compute: []types.MachinePool{
+					{
+						Replicas: ptr.To[int64](1),
+					},
+				},
+			},
+			expectedControlPlane: configv1.HighlyAvailableTopologyMode,
+			expectedInfra:        configv1.HighlyAvailableTopologyMode,
+		},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.desc, func(t *testing.T) {