Report/render both image and container labels

Daemon labels will have to wait since the go client (Docker API v1.14) doesn't support
them yet (daemon labels were exposed in Docker API v1.16)

See https://godoc.org/github.com/fsouza/go-dockerclient#Client.Info for details.

probe/docker/container.go

@@ -10,7 +10,6 @@ import (
 	"net/http"
 	"net/http/httputil"
 	"net/url"
-	"sort"
 	"strconv"
 	"strings"
 	"sync"
@@ -23,12 +22,11 @@ import (
 
 // These constants are keys used in node metadata
 const (
-	ContainerName        = "docker_container_name"
-	ContainerCommand     = "docker_container_command"
-	ContainerPorts       = "docker_container_ports"
-	ContainerCreated     = "docker_container_created"
-	ContainerIPs         = "docker_container_ips"
-	ContainerLabelPrefix = "docker_container_label_"
+	ContainerName    = "docker_container_name"
+	ContainerCommand = "docker_container_command"
+	ContainerPorts   = "docker_container_ports"
+	ContainerCreated = "docker_container_created"
+	ContainerIPs     = "docker_container_ips"
 
 	NetworkRxDropped = "network_rx_dropped"
 	NetworkRxBytes   = "network_rx_bytes"
@@ -218,17 +216,7 @@ func (c *container) GetNodeMetadata() report.NodeMetadata {
 		ContainerIPs: strings.Join(append(c.container.NetworkSettings.SecondaryIPAddresses,
 			c.container.NetworkSettings.IPAddress), " "),
 	})
-
-	// Add labels in alphabetical order
-	labels := c.container.Config.Labels
-	labelKeys := make([]string, 0, len(labels))
-	for k := range labels {
-		labelKeys = append(labelKeys, k)
-	}
-	sort.Strings(labelKeys)
-	for _, labelKey := range labelKeys {
-		result.Metadata[ContainerLabelPrefix+labelKey] = labels[labelKey]
-	}
+	AddLabels(result, c.container.Config.Labels)
 
 	if c.latestStats == nil {
 		return result
@@ -262,15 +250,3 @@ func (c *container) GetNodeMetadata() report.NodeMetadata {
 func ExtractContainerIPs(nmd report.NodeMetadata) []string {
 	return strings.Fields(nmd.Metadata[ContainerIPs])
 }
-
-// ExtractContainerLabels returns the list of Docker container labels given a NodeMetadata from the Container topology.
-func ExtractContainerLabels(nmd report.NodeMetadata) map[string]string {
-	result := map[string]string{}
-	for key, value := range nmd.Metadata {
-		if strings.HasPrefix(key, ContainerLabelPrefix) {
-			label := key[len(ContainerLabelPrefix):]
-			result[label] = value
-		}
-	}
-	return result
-}

probe/docker/labels.go

@@ -0,0 +1,31 @@
+package docker
+
+import (
+	"strings"
+
+	"github.com/weaveworks/scope/report"
+)
+
+// LabelPrefix is the key prefix used for Docker labels in NodeMetadata (e.g. a
+// Docker label "labelKey"="labelValue" will get encoded as
+// "docker_label_labelKey"="dockerValue" in the metadata)
+const LabelPrefix = "docker_label_"
+
+// AddLabels appends Docker labels to the NodeMetadata from a topology.
+func AddLabels(nmd report.NodeMetadata, labels map[string]string) {
+	for key, value := range labels {
+		nmd.Metadata[LabelPrefix+key] = value
+	}
+}
+
+// ExtractLabels returns the list of Docker labels given a NodeMetadata from a topology.
+func ExtractLabels(nmd report.NodeMetadata) map[string]string {
+	result := map[string]string{}
+	for key, value := range nmd.Metadata {
+		if strings.HasPrefix(key, LabelPrefix) {
+			label := key[len(LabelPrefix):]
+			result[label] = value
+		}
+	}
+	return result
+}

probe/docker/labels_test.go

@@ -0,0 +1,25 @@
+package docker_test
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/weaveworks/scope/probe/docker"
+	"github.com/weaveworks/scope/report"
+	"github.com/weaveworks/scope/test"
+)
+
+func TestLabels(t *testing.T) {
+	want := map[string]string{
+		"foo1": "bar1",
+		"foo2": "bar2",
+	}
+	nmd := report.MakeNodeMetadata()
+
+	docker.AddLabels(nmd, want)
+	have := docker.ExtractLabels(nmd)
+
+	if !reflect.DeepEqual(want, have) {
+		t.Error(test.Diff(want, have))
+	}
+}

probe/docker/reporter.go

@@ -52,6 +52,7 @@ func (r *Reporter) containerImageTopology() report.Topology {
 		nmd := report.MakeNodeMetadataWith(map[string]string{
 			ImageID: image.ID,
 		})
+		AddLabels(nmd, image.Labels)
 
 		if len(image.RepoTags) > 0 {
 			nmd.Metadata[ImageName] = image.RepoTags[0]

render/detailed_node.go

@@ -312,11 +312,7 @@ func containerOriginTable(nmd report.NodeMetadata, addHostTag bool) (Table, bool
 	for _, ip := range docker.ExtractContainerIPs(nmd) {
 		rows = append(rows, Row{Key: "IP Address", ValueMajor: ip, ValueMinor: ""})
 	}
-
-	for labelKey, labelValue := range docker.ExtractContainerLabels(nmd) {
-		rows = append(rows, Row{Key: fmt.Sprintf("Label %q", labelKey), ValueMajor: labelValue})
-
-	}
+	rows = append(rows, getDockerLabelRows(nmd)...)
 
 	if val, ok := nmd.Metadata[docker.MemoryUsage]; ok {
 		memory, err := strconv.ParseFloat(val, 64)
@@ -354,6 +350,7 @@ func containerImageOriginTable(nmd report.NodeMetadata) (Table, bool) {
 			rows = append(rows, Row{Key: tuple.human, ValueMajor: val, ValueMinor: ""})
 		}
 	}
+	rows = append(rows, getDockerLabelRows(nmd)...)
 	title := "Container Image"
 	var (
 		nameFound bool
@@ -370,6 +367,21 @@ func containerImageOriginTable(nmd report.NodeMetadata) (Table, bool) {
 	}, len(rows) > 0 || nameFound
 }
 
+func getDockerLabelRows(nmd report.NodeMetadata) []Row {
+	rows := []Row{}
+	// Add labels in alphabetical order
+	labels := docker.ExtractLabels(nmd)
+	labelKeys := make([]string, 0, len(labels))
+	for k := range labels {
+		labelKeys = append(labelKeys, k)
+	}
+	sort.Strings(labelKeys)
+	for _, labelKey := range labelKeys {
+		rows = append(rows, Row{Key: fmt.Sprintf("Label %q", labelKey), ValueMajor: labels[labelKey]})
+	}
+	return rows
+}
+
 func hostOriginTable(nmd report.NodeMetadata) (Table, bool) {
 	rows := []Row{}
 	for _, tuple := range []struct{ key, human string }{

test/report_fixture.go

@@ -174,12 +174,12 @@ var (
 					report.HostNodeID:    ClientHostNodeID,
 				}),
 				ServerContainerNodeID: report.MakeNodeMetadataWith(map[string]string{
-					docker.ContainerID:                   ServerContainerID,
-					docker.ContainerName:                 "server",
-					docker.ImageID:                       ServerContainerImageID,
-					report.HostNodeID:                    ServerHostNodeID,
-					docker.ContainerLabelPrefix + "foo1": "bar1",
-					docker.ContainerLabelPrefix + "foo2": "bar2",
+					docker.ContainerID:          ServerContainerID,
+					docker.ContainerName:        "server",
+					docker.ImageID:              ServerContainerImageID,
+					report.HostNodeID:           ServerHostNodeID,
+					docker.LabelPrefix + "foo1": "bar1",
+					docker.LabelPrefix + "foo2": "bar2",
 				}),
 			},
 		},
@@ -191,9 +191,11 @@ var (
 					report.HostNodeID: ClientHostNodeID,
 				}),
 				ServerContainerImageNodeID: report.MakeNodeMetadataWith(map[string]string{
-					docker.ImageID:    ServerContainerImageID,
-					docker.ImageName:  ServerContainerImageName,
-					report.HostNodeID: ServerHostNodeID,
+					docker.ImageID:              ServerContainerImageID,
+					docker.ImageName:            ServerContainerImageName,
+					report.HostNodeID:           ServerHostNodeID,
+					docker.LabelPrefix + "foo1": "bar1",
+					docker.LabelPrefix + "foo2": "bar2",
 				}),
 			},
 		},