Expose multiple network interfaces in API.

Part of google#686

api/versions.go

@@ -426,8 +426,7 @@ func convertStats(cont *info.ContainerInfo) []v2.ContainerStats {
 			stat.Memory = val.Memory
 		}
 		if stat.HasNetwork {
-			// TODO(rjnagal): Return stats about all network interfaces.
-			stat.Network = append(stat.Network, val.Network)
+			stat.Network.Interfaces = val.Network.Interfaces
 		}
 		if stat.HasFilesystem {
 			stat.Filesystem = val.Filesystem

container/docker/handler.go

@@ -261,17 +261,10 @@ func (self *dockerContainerHandler) GetStats() (*info.ContainerStats, error) {
 	}
 
 	// TODO(rjnagal): Remove the conversion when network stats are read from libcontainer.
-	net := stats.Network
-	// Ingress for host veth is from the container.
-	// Hence tx_bytes stat on the host veth is actually number of bytes received by the container.
-	stats.Network.RxBytes = net.TxBytes
-	stats.Network.RxPackets = net.TxPackets
-	stats.Network.RxErrors = net.TxErrors
-	stats.Network.RxDropped = net.TxDropped
-	stats.Network.TxBytes = net.RxBytes
-	stats.Network.TxPackets = net.RxPackets
-	stats.Network.TxErrors = net.RxErrors
-	stats.Network.TxDropped = net.RxDropped
+	convertInterfaceStats(&stats.Network.InterfaceStats)
+	for i := range stats.Network.Interfaces {
+		convertInterfaceStats(&stats.Network.Interfaces[i])
+	}
 
 	// Get filesystem stats.
 	err = self.getFsStats(stats)
@@ -282,6 +275,21 @@ func (self *dockerContainerHandler) GetStats() (*info.ContainerStats, error) {
 	return stats, nil
 }
 
+func convertInterfaceStats(stats *info.InterfaceStats) {
+	net := stats
+
+	// Ingress for host veth is from the container.
+	// Hence tx_bytes stat on the host veth is actually number of bytes received by the container.
+	stats.RxBytes = net.TxBytes
+	stats.RxPackets = net.TxPackets
+	stats.RxErrors = net.TxErrors
+	stats.RxDropped = net.TxDropped
+	stats.TxBytes = net.RxBytes
+	stats.TxPackets = net.RxPackets
+	stats.TxErrors = net.RxErrors
+	stats.TxDropped = net.RxDropped
+}
+
 func (self *dockerContainerHandler) ListContainers(listType container.ListType) ([]info.ContainerReference, error) {
 	if self.name != "/docker" {
 		return []info.ContainerReference{}, nil

container/libcontainer/helpers.go

@@ -84,15 +84,20 @@ func GetStats(cgroupManager cgroups.Manager, networkInterfaces []string) (*info.
 	}
 	stats := toContainerStats(libcontainerStats)
 
-	if len(networkInterfaces) != 0 {
-		// ContainerStats only reports stat for one network device.
-		// TODO(rjnagal): Handle multiple physical network devices.
-		// TODO(rjnagal): Use networking stats directly from libcontainer.
-		stats.Network, err = sysinfo.GetNetworkStats(networkInterfaces[0])
+	// TODO(rjnagal): Use networking stats directly from libcontainer.
+	stats.Network.Interfaces = make([]info.InterfaceStats, len(networkInterfaces))
+	for i := range networkInterfaces {
+		interfaceStats, err := sysinfo.GetNetworkStats(networkInterfaces[i])
 		if err != nil {
 			return stats, err
 		}
+		stats.Network.Interfaces[i] = interfaceStats
 	}
+	// For backwards compatability.
+	if len(networkInterfaces) > 0 {
+		stats.Network.InterfaceStats = stats.Network.Interfaces[0]
+	}
+
 	return stats, nil
 }
 
@@ -213,15 +218,25 @@ func toContainerStats2(s *cgroups.Stats, ret *info.ContainerStats) {
 }
 
 func toContainerStats3(libcontainerStats *libcontainer.Stats, ret *info.ContainerStats) {
-	// TODO(vmarmol): Handle multiple interfaces.
-	ret.Network.RxBytes = libcontainerStats.Interfaces[0].RxBytes
-	ret.Network.RxPackets = libcontainerStats.Interfaces[0].RxPackets
-	ret.Network.RxErrors = libcontainerStats.Interfaces[0].RxErrors
-	ret.Network.RxDropped = libcontainerStats.Interfaces[0].RxDropped
-	ret.Network.TxBytes = libcontainerStats.Interfaces[0].TxBytes
-	ret.Network.TxPackets = libcontainerStats.Interfaces[0].TxPackets
-	ret.Network.TxErrors = libcontainerStats.Interfaces[0].TxErrors
-	ret.Network.TxDropped = libcontainerStats.Interfaces[0].TxDropped
+	ret.Network.Interfaces = make([]info.InterfaceStats, len(libcontainerStats.Interfaces))
+	for i := range libcontainerStats.Interfaces {
+		ret.Network.Interfaces[i] = info.InterfaceStats{
+			Name:      libcontainerStats.Interfaces[i].Name,
+			RxBytes:   libcontainerStats.Interfaces[i].RxBytes,
+			RxPackets: libcontainerStats.Interfaces[i].RxPackets,
+			RxErrors:  libcontainerStats.Interfaces[i].RxErrors,
+			RxDropped: libcontainerStats.Interfaces[i].RxDropped,
+			TxBytes:   libcontainerStats.Interfaces[i].TxBytes,
+			TxPackets: libcontainerStats.Interfaces[i].TxPackets,
+			TxErrors:  libcontainerStats.Interfaces[i].TxErrors,
+			TxDropped: libcontainerStats.Interfaces[i].TxDropped,
+		}
+	}
+
+	// Add to base struct for backwards compatability.
+	if len(ret.Network.Interfaces) > 0 {
+		ret.Network.InterfaceStats = ret.Network.Interfaces[0]
+	}
 }
 
 func toContainerStats(libcontainerStats *libcontainer.Stats) *info.ContainerStats {

info/v1/container.go

@@ -312,7 +312,9 @@ type MemoryStatsMemoryData struct {
 	Pgmajfault uint64 `json:"pgmajfault"`
 }
 
-type NetworkStats struct {
+type InterfaceStats struct {
+	// The name of the interface.
+	Name string `json:"name"`
 	// Cumulative count of bytes received.
 	RxBytes uint64 `json:"rx_bytes"`
 	// Cumulative count of packets received.
@@ -331,6 +333,11 @@ type NetworkStats struct {
 	TxDropped uint64 `json:"tx_dropped"`
 }
 
+type NetworkStats struct {
+	InterfaceStats `json:",inline"`
+	Interfaces     []InterfaceStats `json:"interfaces,omitempty"`
+}
+
 type FsStats struct {
 	// The block device name associated with the filesystem.
 	Device string `json:"device,omitempty"`

info/v2/container.go

@@ -92,8 +92,8 @@ type ContainerStats struct {
 	HasMemory bool           `json:"has_memory"`
 	Memory    v1.MemoryStats `json:"memory,omitempty"`
 	// Network statistics
-	HasNetwork bool              `json:"has_network"`
-	Network    []v1.NetworkStats `json:"network,omitempty"`
+	HasNetwork bool         `json:"has_network"`
+	Network    NetworkStats `json:"network,omitempty"`
 	// Filesystem statistics
 	HasFilesystem bool         `json:"has_filesystem"`
 	Filesystem    []v1.FsStats `json:"filesystem,omitempty"`
@@ -189,3 +189,8 @@ type ProcessInfo struct {
 	CgroupPath    string  `json:"cgroup_path"`
 	Cmd           string  `json:"cmd"`
 }
+
+type NetworkStats struct {
+	// Network stats by interface.
+	Interfaces []v1.InterfaceStats `json:"interfaces,omitempty"`
+}

metrics/prometheus_test.go

@@ -57,14 +57,17 @@ func (p testSubcontainersInfoProvider) SubcontainersInfo(string, *info.Container
 						},
 					},
 					Network: info.NetworkStats{
-						RxBytes:   14,
-						RxPackets: 15,
-						RxErrors:  16,
-						RxDropped: 17,
-						TxBytes:   18,
-						TxPackets: 19,
-						TxErrors:  20,
-						TxDropped: 21,
+						InterfaceStats: info.InterfaceStats{
+							Name:      "eth0",
+							RxBytes:   14,
+							RxPackets: 15,
+							RxErrors:  16,
+							RxDropped: 17,
+							TxBytes:   18,
+							TxPackets: 19,
+							TxErrors:  20,
+							TxDropped: 21,
+						},
 					},
 					Filesystem: []info.FsStats{
 						{

utils/sysinfo/sysinfo.go

@@ -157,19 +157,19 @@ func GetCacheInfo(sysFs sysfs.SysFs, id int) ([]sysfs.CacheInfo, error) {
 	return info, nil
 }
 
-func GetNetworkStats(name string) (info.NetworkStats, error) {
-	stats := info.NetworkStats{}
+func GetNetworkStats(name string) (info.InterfaceStats, error) {
 	// TODO(rjnagal): Take syfs as an argument.
 	sysFs, err := sysfs.NewRealSysFs()
 	if err != nil {
-		return stats, err
+		return info.InterfaceStats{}, err
 	}
 	return getNetworkStats(name, sysFs)
 }
 
-func getNetworkStats(name string, sysFs sysfs.SysFs) (info.NetworkStats, error) {
-	stats := info.NetworkStats{}
+func getNetworkStats(name string, sysFs sysfs.SysFs) (info.InterfaceStats, error) {
+	var stats info.InterfaceStats
 	var err error
+	stats.Name = name
 	stats.RxBytes, err = sysFs.GetNetworkStatValue(name, "rx_bytes")
 	if err != nil {
 		return stats, err

utils/sysinfo/sysinfo_test.go

@@ -110,7 +110,8 @@ func TestGetCacheInfo(t *testing.T) {
 }
 
 func TestGetNetworkStats(t *testing.T) {
-	expected_stats := info.NetworkStats{
+	expected_stats := info.InterfaceStats{
+		Name:      "eth0",
 		RxBytes:   1024,
 		RxPackets: 1024,
 		RxErrors:  1024,