render sensible labels for parent nodes with little/no metadata

We eliminate the custom parent renderer, which was a very partial
implementation MakeBasicNodeSummary.

We also ensure that parents are always rendered in the same, sensible
order. Previously the order was an alphabetic sort of the parent
topology IDs. Now lower level topologies come before higher level
topologies.

render/detailed/node_test.go

@@ -229,16 +229,16 @@ func TestMakeDetailedContainerNode(t *testing.T) {
 					Label:      fixture.ServerContainerImageName,
 					TopologyID: "containers-by-image",
 				},
-				{
-					ID:         fixture.ServerHostNodeID,
-					Label:      fixture.ServerHostName,
-					TopologyID: "hosts",
-				},
 				{
 					ID:         fixture.ServerPodNodeID,
 					Label:      "pong-b",
 					TopologyID: "pods",
 				},
+				{
+					ID:         fixture.ServerHostNodeID,
+					Label:      "server",
+					TopologyID: "hosts",
+				},
 			},
 		},
 		Controls: []detailed.ControlInstance{},
@@ -339,16 +339,16 @@ func TestMakeDetailedPodNode(t *testing.T) {
 				{ID: "kubernetes_namespace", Label: "Namespace", Value: "ping", Priority: 5},
 			},
 			Parents: []detailed.Parent{
-				{
-					ID:         fixture.ServerHostNodeID,
-					Label:      fixture.ServerHostName,
-					TopologyID: "hosts",
-				},
 				{
 					ID:         fixture.ServiceNodeID,
 					Label:      fixture.ServiceName,
 					TopologyID: "services",
 				},
+				{
+					ID:         fixture.ServerHostNodeID,
+					Label:      "server",
+					TopologyID: "hosts",
+				},
 			},
 		},
 		Controls: []detailed.ControlInstance{},

render/detailed/parents.go

@@ -1,12 +1,6 @@
 package detailed
 
 import (
-	"sort"
-
-	"github.com/weaveworks/scope/probe/awsecs"
-	"github.com/weaveworks/scope/probe/docker"
-	"github.com/weaveworks/scope/probe/host"
-	"github.com/weaveworks/scope/probe/kubernetes"
 	"github.com/weaveworks/scope/report"
 )
 
@@ -17,24 +11,21 @@ type Parent struct {
 	TopologyID string `json:"topologyId"`
 }
 
-var (
-	kubernetesParentLabel = latestLookup(kubernetes.Name)
-
-	getLabelForTopology = map[string]func(report.Node) string{
-		report.Container:      getRenderableContainerName,
-		report.Pod:            kubernetesParentLabel,
-		report.Deployment:     kubernetesParentLabel,
-		report.DaemonSet:      kubernetesParentLabel,
-		report.StatefulSet:    kubernetesParentLabel,
-		report.CronJob:        kubernetesParentLabel,
-		report.Service:        kubernetesParentLabel,
-		report.ECSTask:        latestLookup(awsecs.TaskFamily),
-		report.ECSService:     ecsServiceParentLabel,
-		report.SwarmService:   latestLookup(docker.ServiceName),
-		report.ContainerImage: containerImageParentLabel,
-		report.Host:           latestLookup(host.HostName),
-	}
-)
+// parent topologies, in the order we want to show them
+var parentTopologies = []string{
+	report.Container,
+	report.ContainerImage,
+	report.Pod,
+	report.Deployment,
+	report.DaemonSet,
+	report.StatefulSet,
+	report.CronJob,
+	report.Service,
+	report.ECSTask,
+	report.ECSService,
+	report.SwarmService,
+	report.Host,
+}
 
 // Parents renders the parents of this report.Node, which have been aggregated
 // from the probe reports.
@@ -43,13 +34,7 @@ func Parents(r report.Report, n report.Node) []Parent {
 		return nil
 	}
 	result := make([]Parent, 0, n.Parents.Size())
-	topologyIDs := []string{}
-	for topologyID := range getLabelForTopology {
-		topologyIDs = append(topologyIDs, topologyID)
-	}
-	sort.Strings(topologyIDs)
-	for _, topologyID := range topologyIDs {
-		getLabel := getLabelForTopology[topologyID]
+	for _, topologyID := range parentTopologies {
 		topology, ok := r.Topology(topologyID)
 		if !ok {
 			continue
@@ -63,7 +48,7 @@ func Parents(r report.Report, n report.Node) []Parent {
 			var parentNode report.Node
 			// Special case: container image parents should be empty nodes for some reason
 			if topologyID == report.ContainerImage {
-				parentNode = report.MakeNode(id)
+				parentNode = report.MakeNode(id).WithTopology(topologyID)
 			} else {
 				if parent, ok := topology.Nodes[id]; ok {
 					parentNode = parent
@@ -76,33 +61,17 @@ func Parents(r report.Report, n report.Node) []Parent {
 			if !ok {
 				continue
 			}
-
-			result = append(result, Parent{
-				ID:         id,
-				Label:      getLabel(parentNode),
-				TopologyID: apiTopologyID,
-			})
+			if summary, ok := MakeBasicNodeSummary(r, parentNode); ok {
+				result = append(result, Parent{
+					ID:         summary.ID,
+					Label:      summary.Label,
+					TopologyID: apiTopologyID,
+				})
+			}
 		}
 	}
 	if len(result) == 0 {
 		return nil
 	}
 	return result
 }
-
-func latestLookup(key string) func(report.Node) string {
-	return func(n report.Node) string {
-		value, _ := n.Latest.Lookup(key)
-		return value
-	}
-}
-
-func ecsServiceParentLabel(n report.Node) string {
-	_, name, _ := report.ParseECSServiceNodeID(n.ID)
-	return name
-}
-
-func containerImageParentLabel(n report.Node) string {
-	name, _ := report.ParseContainerImageNodeID(n.ID)
-	return name
-}

render/detailed/parents_test.go

@@ -34,23 +34,23 @@ func TestParents(t *testing.T) {
 			name: "Container image",
 			node: render.ContainerImageRenderer.Render(fixture.Report).Nodes[expected.ClientContainerImageNodeID],
 			want: []detailed.Parent{
-				{ID: fixture.ClientHostNodeID, Label: fixture.ClientHostName, TopologyID: "hosts"},
+				{ID: fixture.ClientHostNodeID, Label: "client", TopologyID: "hosts"},
 			},
 		},
 		{
 			name: "Container",
 			node: render.ContainerWithImageNameRenderer.Render(fixture.Report).Nodes[fixture.ClientContainerNodeID],
 			want: []detailed.Parent{
 				{ID: expected.ClientContainerImageNodeID, Label: fixture.ClientContainerImageName, TopologyID: "containers-by-image"},
-				{ID: fixture.ClientHostNodeID, Label: fixture.ClientHostName, TopologyID: "hosts"},
 				{ID: fixture.ClientPodNodeID, Label: "pong-a", TopologyID: "pods"},
+				{ID: fixture.ClientHostNodeID, Label: "client", TopologyID: "hosts"},
 			},
 		},
 		{
 			node: render.ProcessRenderer.Render(fixture.Report).Nodes[fixture.ClientProcess1NodeID],
 			want: []detailed.Parent{
 				{ID: fixture.ClientContainerNodeID, Label: fixture.ClientContainerName, TopologyID: "containers"},
-				{ID: fixture.ClientHostNodeID, Label: fixture.ClientHostName, TopologyID: "hosts"},
+				{ID: fixture.ClientHostNodeID, Label: "client", TopologyID: "hosts"},
 			},
 		},
 	} {