assume no overhead if it cannot be calculated (#1935)

* assume no overhead if it cannot be calculated

Signed-off-by: Alex Meijer <ameijer@kubecost.com>

* rm dead comment, add additional nil check

Signed-off-by: Alex Meijer <ameijer@kubecost.com>

* warnf fix

Signed-off-by: Alex Meijer <ameijer@kubecost.com>

* fix tests

Signed-off-by: Alex Meijer <ameijer@kubecost.com>

---------

Signed-off-by: Alex Meijer <ameijer@kubecost.com>

pkg/costmodel/assets.go

@@ -134,11 +134,15 @@ func (cm *CostModel) ComputeAssets(start, end time.Time) (*kubecost.AssetSet, er
 		node.GPUCount = n.GPUCount
 		node.RAMCost = n.RAMCost
 
-		node.Overhead = &kubecost.NodeOverhead{
-			RamOverheadFraction: n.Overhead.RamOverheadFraction,
-			CpuOverheadFraction: n.Overhead.CpuOverheadFraction,
-			OverheadCostFraction: ((n.Overhead.CpuOverheadFraction * n.CPUCost) +
-				(n.Overhead.RamOverheadFraction * n.RAMCost)) / node.TotalCost(),
+		if n.Overhead != nil {
+			node.Overhead = &kubecost.NodeOverhead{
+				RamOverheadFraction: n.Overhead.RamOverheadFraction,
+				CpuOverheadFraction: n.Overhead.CpuOverheadFraction,
+				OverheadCostFraction: ((n.Overhead.CpuOverheadFraction * n.CPUCost) +
+					(n.Overhead.RamOverheadFraction * n.RAMCost)) / node.TotalCost(),
+			}
+		} else {
+			node.Overhead = &kubecost.NodeOverhead{}
 		}
 		node.Discount = n.Discount
 		if n.Preemptible {

pkg/costmodel/cluster_helpers.go

@@ -825,6 +825,11 @@ func buildNodeMap(
 
 		if overhead, ok := overheadMap[clusterAndNameID]; ok {
 			nodePtr.Overhead = overhead
+		} else {
+			// we were unable to compute overhead for this node
+			// assume default case of no overhead
+			nodePtr.Overhead = &NodeOverhead{}
+			log.Warnf("unable to compute overhead for node %s - defaulting to no overhead", clusterAndNameID.Name)
 		}
 
 	}

pkg/costmodel/cluster_helpers_test.go

@@ -184,6 +184,7 @@ func TestBuildNodeMap(t *testing.T) {
 					CPUCost:      0.048,
 					CPUBreakdown: &ClusterCostsBreakdown{},
 					RAMBreakdown: &ClusterCostsBreakdown{},
+					Overhead:     &NodeOverhead{},
 				},
 			},
 		},
@@ -212,6 +213,7 @@ func TestBuildNodeMap(t *testing.T) {
 					CPUCost:      0.048,
 					CPUBreakdown: &ClusterCostsBreakdown{},
 					RAMBreakdown: &ClusterCostsBreakdown{},
+					Overhead:     &NodeOverhead{},
 				},
 			},
 		},
@@ -248,6 +250,7 @@ func TestBuildNodeMap(t *testing.T) {
 					CPUCost:      0.048,
 					CPUBreakdown: &ClusterCostsBreakdown{},
 					RAMBreakdown: &ClusterCostsBreakdown{},
+					Overhead:     &NodeOverhead{},
 				},
 				{
 					Cluster:    "cluster1",
@@ -261,6 +264,7 @@ func TestBuildNodeMap(t *testing.T) {
 					CPUCost:      0.087,
 					CPUBreakdown: &ClusterCostsBreakdown{},
 					RAMBreakdown: &ClusterCostsBreakdown{},
+					Overhead:     &NodeOverhead{},
 				},
 			},
 		},
@@ -490,6 +494,7 @@ func TestBuildNodeMap(t *testing.T) {
 					End:         time.Date(2020, 6, 16, 9, 20, 39, 0, time.UTC),
 					Minutes:     5*60 + 35 + (11.0 / 60.0),
 					Preemptible: true,
+					Overhead:    &NodeOverhead{},
 					Labels: map[string]string{
 						"labelname1_A": "labelvalue1_A",
 						"labelname1_B": "labelvalue1_B",
@@ -526,6 +531,7 @@ func TestBuildNodeMap(t *testing.T) {
 						"labelname1_A": "labelvalue1_A",
 						"labelname1_B": "labelvalue1_B",
 					},
+					Overhead: &NodeOverhead{},
 				},
 				{
 					Cluster:    "cluster1",
@@ -558,6 +564,7 @@ func TestBuildNodeMap(t *testing.T) {
 						"labelname2_A": "labelvalue2_A",
 						"labelname2_B": "labelvalue2_B",
 					},
+					Overhead: &NodeOverhead{},
 				},
 			},
 		},
@@ -596,6 +603,7 @@ func TestBuildNodeMap(t *testing.T) {
 					CPUCores:     partialCPUMap["e2-micro"],
 					CPUBreakdown: &ClusterCostsBreakdown{},
 					RAMBreakdown: &ClusterCostsBreakdown{},
+					Overhead:     &NodeOverhead{},
 				},
 			},
 		},
@@ -634,6 +642,7 @@ func TestBuildNodeMap(t *testing.T) {
 					CPUCores:     partialCPUMap["e2-small"],
 					CPUBreakdown: &ClusterCostsBreakdown{},
 					RAMBreakdown: &ClusterCostsBreakdown{},
+					Overhead:     &NodeOverhead{},
 				},
 			},
 		},