Merge pull request #400 from weaveworks/docker-labels

Report docker container labels and render them in the details pane

probe/docker/container.go

@@ -216,6 +216,7 @@ func (c *container) GetNodeMetadata() report.NodeMetadata {
 		ContainerIPs: strings.Join(append(c.container.NetworkSettings.SecondaryIPAddresses,
 			c.container.NetworkSettings.IPAddress), " "),
 	})
+	AddLabels(result, c.container.Config.Labels)
 
 	if c.latestStats == nil {
 		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/registry_test.go

@@ -106,12 +106,24 @@ var (
 		NetworkSettings: &client.NetworkSettings{
 			IPAddress: "1.2.3.4",
 		},
+		Config: &client.Config{
+			Labels: map[string]string{
+				"foo1": "bar1",
+				"foo2": "bar2",
+			},
+		},
 	}
 	container2 = &client.Container{
 		ID:    "wiff",
 		Name:  "waff",
 		Image: "baz",
 		State: client.State{Pid: 1, Running: true},
+		Config: &client.Config{
+			Labels: map[string]string{
+				"foo1": "bar1",
+				"foo2": "bar2",
+			},
+		},
 	}
 	apiContainer1 = client.APIContainers{ID: "ping"}
 	apiImage1     = client.APIImages{ID: "baz", RepoTags: []string{"bang", "not-chosen"}}

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]