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probe/docker/container.go

@@ -71,6 +71,7 @@ type Container interface {
 	ID() string
 	Image() string
 	PID() int
+	Hostname() string
 	GetNode([]net.IP) report.Node
 
 	StartGatheringStats() error
@@ -101,6 +102,15 @@ func (c *container) PID() int {
 	return c.container.State.Pid
 }
 
+func (c *container) Hostname() string {
+	if c.container.Config.Domainname == "" {
+		return c.container.Config.Hostname
+	}
+
+	return fmt.Sprintf("%s.%s", c.container.Config.Hostname,
+		c.container.Config.Domainname)
+}
+
 func (c *container) StartGatheringStats() error {
 	c.Lock()
 	defer c.Unlock()
@@ -222,7 +232,7 @@ func (c *container) GetNode(localAddrs []net.IP) report.Node {
 		ImageID:          c.container.Image,
 		ContainerIPs: strings.Join(append(c.container.NetworkSettings.SecondaryIPAddresses,
 			c.container.NetworkSettings.IPAddress), " "),
-		ContainerHostname: c.container.Config.Hostname,
+		ContainerHostname: c.Hostname(),
 	})
 	AddLabels(result, c.container.Config.Labels)
 

probe/docker/registry_test.go

@@ -31,6 +31,10 @@ func (c *mockContainer) Image() string {
 	return c.c.Image
 }
 
+func (c *mockContainer) Hostname() string {
+	return ""
+}
+
 func (c *mockContainer) StartGatheringStats() error {
 	return nil
 }

render/mapping.go

@@ -484,7 +484,7 @@ func MapContainer2ContainerImage(n RenderableNode, _ report.Networks) Renderable
 		return RenderableNodes{}
 	}
 
-	// Add container-<id> key to NMD, which will later be counted to produce the minor label
+	// Add container id key to the counters, which will later be counted to produce the minor label
 	result := NewDerivedNode(id, n)
 	result.Node.Counters[containersKey] = 1
 	return RenderableNodes{id: result}
@@ -608,10 +608,11 @@ func MapContainer2Hostname(n RenderableNode, _ report.Networks) RenderableNodes
 		return RenderableNodes{}
 	}
 
-	// Add container-<id> key to NMD, which will later be counted to produce the minor label
 	result := NewDerivedNode(id, n)
 	result.LabelMajor = id
 	result.Rank = id
+
+	// Add container id key to the counters, which will later be counted to produce the minor label
 	result.Node.Counters[containersKey] = 1
 	return RenderableNodes{id: result}
 }

render/topologies.go

@@ -176,17 +176,8 @@ var ContainerImageRenderer = Map{
 var ContainerHostnameRenderer = Map{
 	MapFunc: MapCountContainers,
 	Renderer: Map{
-		MapFunc: MapContainer2Hostname,
-		Renderer: MakeReduce(
-			Map{
-				MapFunc:  MapContainer2ContainerImage,
-				Renderer: ContainerRenderer,
-			},
-			Map{
-				MapFunc:  MapContainerImageIdentity,
-				Renderer: SelectContainerImage,
-			},
-		),
+		MapFunc:  MapContainer2Hostname,
+		Renderer: ContainerRenderer,
 	},
 }