Add ContainerImage topology and use it to build the Container By Imag…

…e graph.

This makes container image details show the containers (and processes) correctly.

Also:
- introduces a 'test' package, moved Diff function there.
- adds some tests for this new rendered view.

app/router.go

@@ -65,7 +65,7 @@ var topologyRegistry = map[string]topologyView{
 	"containers-by-image": {
 		human:    "by image",
 		parent:   "containers",
-		renderer: render.LeafMap{Selector: report.SelectEndpoint, Mapper: render.ProcessContainerImage, Pseudo: render.InternetOnlyPseudoNode},
+		renderer: render.ContainerImageRenderer,
 	},
 	"hosts": {
 		human:    "Hosts",

probe/main.go

@@ -130,6 +130,7 @@ func main() {
 
 				if dockerTagger != nil {
 					r.Container.Merge(dockerTagger.ContainerTopology(hostID))
+					r.ContainerImage.Merge(dockerTagger.ContainerImageTopology(hostID))
 				}
 
 				if weaveTagger != nil {

probe/tag/docker_tagger.go

@@ -272,7 +272,6 @@ func (t *DockerTagger) Containers() []*docker.Container {
 // Tag implements Tagger.
 func (t *DockerTagger) Tag(r report.Report) report.Report {
 	t.tag(&r.Process)
-	t.tag(&r.Endpoint)
 	return r
 }
 
@@ -313,15 +312,6 @@ func (t *DockerTagger) tag(topology *report.Topology) {
 
 		md := report.NodeMetadata{
 			ContainerID: container.ID,
-			ImageID:     container.Image,
-		}
-
-		t.RLock()
-		image, ok := t.images[container.Image]
-		t.RUnlock()
-
-		if ok && len(image.RepoTags) > 0 {
-			md[ImageName] = image.RepoTags[0]
 		}
 
 		topology.NodeMetadatas[nodeID].Merge(md)
@@ -341,14 +331,33 @@ func (t *DockerTagger) ContainerTopology(scope string) report.Topology {
 			ImageID:       container.Image,
 		}
 
+		nmd.Merge(container.getStats())
+
+		nodeID := report.MakeContainerNodeID(scope, container.ID)
+		result.NodeMetadatas[nodeID] = nmd
+	}
+	return result
+}
+
+// ContainerImageTopology produces a Toplogy of Container Images
+func (t *DockerTagger) ContainerImageTopology(scope string) report.Topology {
+	t.RLock()
+	defer t.RUnlock()
+
+	result := report.NewTopology()
+
+	// Loop over containers so we only emit images for running containers.
+	for _, container := range t.containers {
+		nmd := report.NodeMetadata{
+			ImageID: container.Image,
+		}
+
 		image, ok := t.images[container.Image]
 		if ok && len(image.RepoTags) > 0 {
 			nmd[ImageName] = image.RepoTags[0]
 		}
 
-		nmd.Merge(container.getStats())
-
-		nodeID := report.MakeContainerNodeID(scope, container.ID)
+		nodeID := report.MakeContainerNodeID(scope, container.Image)
 		result.NodeMetadatas[nodeID] = nmd
 	}
 	return result

probe/tag/docker_tagger_test.go

@@ -8,6 +8,7 @@ import (
 
 	docker "github.com/fsouza/go-dockerclient"
 	"github.com/weaveworks/scope/report"
+	"github.com/weaveworks/scope/test"
 )
 
 type mockDockerClient struct {
@@ -69,16 +70,29 @@ func TestDockerTagger(t *testing.T) {
 	var (
 		pid1NodeID           = report.MakeProcessNodeID("somehost.com", "1")
 		pid2NodeID           = report.MakeProcessNodeID("somehost.com", "2")
-		endpointNodeMetadata = report.NodeMetadata{
+		processNodeMetadata = report.NodeMetadata{
 			ContainerID: "foo",
-			ImageID:     "baz",
-			ImageName:   "bang",
 		}
-		processNodeMetadata = report.NodeMetadata{
-			ContainerID:   "foo",
-			ContainerName: "bar",
-			ImageID:       "baz",
-			ImageName:     "bang",
+		wantContainerTopology = report.Topology{
+			Adjacency:     report.Adjacency{},
+			EdgeMetadatas: report.EdgeMetadatas{},
+			NodeMetadatas: report.NodeMetadatas{
+				report.MakeContainerNodeID("", "foo"): report.NodeMetadata{
+					ContainerID:   "foo",
+					ContainerName: "bar",
+					ImageID:       "baz",
+				},
+			},
+		}
+		wantContainerImageTopology = report.Topology{
+			Adjacency:     report.Adjacency{},
+			EdgeMetadatas: report.EdgeMetadatas{},
+			NodeMetadatas: report.NodeMetadatas{
+				report.MakeContainerNodeID("", "baz"): report.NodeMetadata{
+					ImageID:   "baz",
+					ImageName: "bang",
+				},
+			},
 		}
 	)
 
@@ -89,18 +103,21 @@ func TestDockerTagger(t *testing.T) {
 	dockerTagger, _ := NewDockerTagger("/irrelevant", 10*time.Second)
 	runtime.Gosched()
 	for _, nodeID := range []string{pid1NodeID, pid2NodeID} {
-		want := endpointNodeMetadata.Copy()
+		want := processNodeMetadata.Copy()
 		have := dockerTagger.Tag(r).Process.NodeMetadatas[nodeID].Copy()
 		delete(have, "pid")
 		if !reflect.DeepEqual(want, have) {
 			t.Errorf("%q: want %+v, have %+v", nodeID, want, have)
 		}
 	}
 
-	wantTopology := report.NewTopology()
-	wantTopology.NodeMetadatas[report.MakeContainerNodeID("", "foo")] = processNodeMetadata
-	haveTopology := dockerTagger.ContainerTopology("")
-	if !reflect.DeepEqual(wantTopology, haveTopology) {
-		t.Errorf("toplog want %+v, have %+v", wantTopology, haveTopology)
+	haveContainerTopology := dockerTagger.ContainerTopology("")
+	if !reflect.DeepEqual(wantContainerTopology, haveContainerTopology) {
+		t.Errorf("%s", test.Diff(wantContainerTopology, haveContainerTopology))
+	}
+
+	haveContainerImageTopology := dockerTagger.ContainerImageTopology("")
+	if !reflect.DeepEqual(wantContainerImageTopology, haveContainerImageTopology) {
+		t.Errorf("%s", test.Diff(wantContainerImageTopology, haveContainerImageTopology))
 	}
 }

render/detailed_node.go

@@ -93,6 +93,9 @@ func OriginTable(r report.Report, originID string) (Table, bool) {
 	if nmd, ok := r.Container.NodeMetadatas[originID]; ok {
 		return containerOriginTable(nmd)
 	}
+	if nmd, ok := r.ContainerImage.NodeMetadatas[originID]; ok {
+		return containerImageOriginTable(nmd)
+	}
 	if nmd, ok := r.Host.NodeMetadatas[originID]; ok {
 		return hostOriginTable(nmd)
 	}
@@ -155,7 +158,6 @@ func containerOriginTable(nmd report.NodeMetadata) (Table, bool) {
 		{"docker_container_id", "Container ID"},
 		{"docker_container_name", "Container name"},
 		{"docker_image_id", "Container image ID"},
-		{"docker_image_name", "Container image name"},
 	} {
 		if val, ok := nmd[tuple.key]; ok {
 			rows = append(rows, Row{Key: tuple.human, ValueMajor: val, ValueMinor: ""})
@@ -168,6 +170,23 @@ func containerOriginTable(nmd report.NodeMetadata) (Table, bool) {
 	}, len(rows) > 0
 }
 
+func containerImageOriginTable(nmd report.NodeMetadata) (Table, bool) {
+	rows := []Row{}
+	for _, tuple := range []struct{ key, human string }{
+		{"docker_image_id", "Container image ID"},
+		{"docker_image_name", "Container image name"},
+	} {
+		if val, ok := nmd[tuple.key]; ok {
+			rows = append(rows, Row{Key: tuple.human, ValueMajor: val, ValueMinor: ""})
+		}
+	}
+	return Table{
+		Title:   "Origin Container Image",
+		Numeric: false,
+		Rows:    rows,
+	}, len(rows) > 0
+}
+
 func hostOriginTable(nmd report.NodeMetadata) (Table, bool) {
 	rows := []Row{}
 	if val, ok := nmd["host_name"]; ok {

render/detailed_node_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/weaveworks/scope/render"
+	"github.com/weaveworks/scope/test"
 )
 
 func TestOriginTable(t *testing.T) {
@@ -51,7 +52,7 @@ func TestOriginTable(t *testing.T) {
 			continue
 		}
 		if !reflect.DeepEqual(want, have) {
-			t.Errorf("%q: %s", originID, diff(want, have))
+			t.Errorf("%q: %s", originID, test.Diff(want, have))
 		}
 	}
 }
@@ -95,6 +96,7 @@ func TestMakeDetailedNode(t *testing.T) {
 				Rows: []render.Row{
 					{"Container ID", "5e4d3c2b1a", ""},
 					{"Container name", "server", ""},
+					{"Container image ID", "imageid456", ""},
 				},
 			},
 			{
@@ -109,6 +111,6 @@ func TestMakeDetailedNode(t *testing.T) {
 		},
 	}
 	if !reflect.DeepEqual(want, have) {
-		t.Errorf("%s", diff(want, have))
+		t.Errorf("%s", test.Diff(want, have))
 	}
 }

render/mapping.go

@@ -87,6 +87,19 @@ func MapContainerIdentity(m report.NodeMetadata) (RenderableNode, bool) {
 	return NewRenderableNode(id, major, minor, rank, m), true
 }
 
+// MapContainerImageIdentity maps a container image topology node to container
+// image RenderableNode node. As it is only ever run on container image
+// topology nodes, we can safely assume the presences of certain keys.
+func MapContainerImageIdentity(m report.NodeMetadata) (RenderableNode, bool) {
+	var (
+		id    = m["docker_image_id"]
+		major = m["docker_image_name"]
+		rank  = m["docker_image_id"]
+	)
+
+	return NewRenderableNode(id, major, "", rank, m), true
+}
+
 // MapEndpoint2Process maps endpoint RenderableNodes to process
 // RenderableNodes.
 //
@@ -156,18 +169,24 @@ func MapProcess2Name(n RenderableNode) (RenderableNode, bool) {
 	return node, true
 }
 
-// ProcessContainerImage maps topology nodes to the container images they run
-// on. If no container metadata is found, nodes are grouped into the
-// Uncontained node.
-func ProcessContainerImage(m report.NodeMetadata) (RenderableNode, bool) {
-	var id, major, minor, rank string
-	if m["docker_image_id"] == "" {
-		id, major, minor, rank = UncontainedID, UncontainedMajor, "", UncontainedID
-	} else {
-		id, major, minor, rank = m["docker_image_id"], m["docker_image_name"], "", m["docker_image_id"]
+// MapContainer2ContainerImage maps container RenderableNodes to container
+// image RenderableNodes.
+//
+// If this function is given a node without a docker_image_id
+// (including other pseudo nodes), it will produce an "Uncontained"
+// pseudo node.
+//
+// Otherwise, this function will produce a node with the correct ID
+// format for a container, but without any Major or Minor labels.
+// It does not have enough info to do that, and the resulting graph
+// must be merged with a container graph to get that info.
+func MapContainer2ContainerImage(n RenderableNode) (RenderableNode, bool) {
+	id, ok := n.NodeMetadata["docker_image_id"]
+	if !ok || n.Pseudo {
+		return newDerivedPseudoNode(UncontainedID, UncontainedMajor, n), true
 	}
 
-	return NewRenderableNode(id, major, minor, rank, m), true
+	return newDerivedNode(id, n), true
 }
 
 // NetworkHostname takes a node NodeMetadata and returns a representation

render/topologies.go

@@ -45,3 +45,17 @@ var ContainerRenderer = MakeReduce(
 		Pseudo:   GenericPseudoNode,
 	},
 )
+
+// ContainerImageRenderer is a Renderer which produces a renderable container
+// image graph by merging the container graph and the container image topology.
+var ContainerImageRenderer = MakeReduce(
+	Map{
+		MapFunc:  MapContainer2ContainerImage,
+		Renderer: ContainerRenderer,
+	},
+	LeafMap{
+		Selector: report.SelectContainerImage,
+		Mapper:   MapContainerImageIdentity,
+		Pseudo:   GenericPseudoNode,
+	},
+)