Add ethernet devices information to machine endpoint.

info/machine.go

@@ -95,6 +95,20 @@ type DiskInfo struct {
 	Size uint64 `json:"size"`
 }
 
+type NetInfo struct {
+	// Device name
+	Name string `json:"name"`
+
+	// Mac Address
+	MacAddress string `json:"mac_address"`
+
+	// Speed in MBits/s
+	Speed uint64 `json:"speed"`
+
+	// Maximum Transmission Unit
+	Mtu uint64 `json:"mtu"`
+}
+
 type MachineInfo struct {
 	// The number of cores in this machine.
 	NumCores int `json:"num_cores"`
@@ -111,6 +125,9 @@ type MachineInfo struct {
 	// Disk map
 	DiskMap map[string]DiskInfo `json:"disk_map"`
 
+	// Network devices
+	NetworkDevices []NetInfo `json:"network_devices"`
+
 	// Machine Topology
 	// Describes cpu layout and hierarchy. TODO(rjnagal): Add Memory hierarchy.
 	Topology []Node `json:"topology"`

manager/machine.go

@@ -235,6 +235,11 @@ func getMachineInfo(sysFs sysfs.SysFs) (*info.MachineInfo, error) {
 		return nil, err
 	}
 
+	netDevices, err := sysfs.GetNetworkDevices(sysFs)
+	if err != nil {
+		return nil, err
+	}
+
 	topology, numCores, err := getTopology(sysFs, string(cpuinfo))
 	if err != nil {
 		return nil, err
@@ -245,6 +250,7 @@ func getMachineInfo(sysFs sysfs.SysFs) (*info.MachineInfo, error) {
 		CpuFrequency:   clockSpeed,
 		MemoryCapacity: memoryCapacity,
 		DiskMap:        diskMap,
+		NetworkDevices: netDevices,
 		Topology:       topology,
 	}
 

utils/sysfs/fakesysfs/fake.go

@@ -68,6 +68,23 @@ func (self *FakeSysFs) GetBlockDeviceNumbers(name string) (string, error) {
 	return "8:0\n", nil
 }
 
+func (self *FakeSysFs) GetNetworkDevices() ([]os.FileInfo, error) {
+	self.info.EntryName = "eth0"
+	return []os.FileInfo{&self.info}, nil
+}
+
+func (self *FakeSysFs) GetNetworkAddress(name string) (string, error) {
+	return "42:01:02:03:04:f4\n", nil
+}
+
+func (self *FakeSysFs) GetNetworkMtu(name string) (string, error) {
+	return "1024\n", nil
+}
+
+func (self *FakeSysFs) GetNetworkSpeed(name string) (string, error) {
+	return "1000\n", nil
+}
+
 func (self *FakeSysFs) GetCaches(id int) ([]os.FileInfo, error) {
 	self.info.EntryName = "index0"
 	return []os.FileInfo{&self.info}, nil

utils/sysfs/sysfs.go

@@ -28,6 +28,7 @@ import (
 const (
 	blockDir = "/sys/block"
 	cacheDir = "/sys/devices/system/cpu/cpu"
+	netDir   = "/sys/class/net"
 )
 
 // Abstracts the lowest level calls to sysfs.
@@ -39,6 +40,11 @@ type SysFs interface {
 	// Get device major:minor number string.
 	GetBlockDeviceNumbers(string) (string, error)
 
+	GetNetworkDevices() ([]os.FileInfo, error)
+	GetNetworkAddress(string) (string, error)
+	GetNetworkMtu(string) (string, error)
+	GetNetworkSpeed(string) (string, error)
+
 	// Get directory information for available caches accessible to given cpu.
 	GetCaches(id int) ([]os.FileInfo, error)
 	// Get information for a cache accessible from the given cpu.
@@ -71,6 +77,34 @@ func (self *realSysFs) GetBlockDeviceSize(name string) (string, error) {
 	return string(size), nil
 }
 
+func (self *realSysFs) GetNetworkDevices() ([]os.FileInfo, error) {
+	return ioutil.ReadDir(netDir)
+}
+
+func (self *realSysFs) GetNetworkAddress(name string) (string, error) {
+	address, err := ioutil.ReadFile(path.Join(netDir, name, "/address"))
+	if err != nil {
+		return "", err
+	}
+	return string(address), nil
+}
+
+func (self *realSysFs) GetNetworkMtu(name string) (string, error) {
+	mtu, err := ioutil.ReadFile(path.Join(netDir, name, "/mtu"))
+	if err != nil {
+		return "", err
+	}
+	return string(mtu), nil
+}
+
+func (self *realSysFs) GetNetworkSpeed(name string) (string, error) {
+	speed, err := ioutil.ReadFile(path.Join(netDir, name, "/speed"))
+	if err != nil {
+		return "", err
+	}
+	return string(speed), nil
+}
+
 func (self *realSysFs) GetCaches(id int) ([]os.FileInfo, error) {
 	cpuPath := fmt.Sprintf("%s%d/cache", cacheDir, id)
 	return ioutil.ReadDir(cpuPath)
@@ -161,6 +195,52 @@ func GetBlockDeviceInfo(sysfs SysFs) (map[string]info.DiskInfo, error) {
 	return diskMap, nil
 }
 
+// Get information about network devices present on the system.
+func GetNetworkDevices(sysfs SysFs) ([]info.NetInfo, error) {
+	devs, err := sysfs.GetNetworkDevices()
+	if err != nil {
+		return nil, err
+	}
+	netDevices := []info.NetInfo{}
+	for _, dev := range devs {
+		name := dev.Name()
+		// Only consider ethernet devices for now.
+		if !strings.HasPrefix(name, "eth") {
+			continue
+		}
+		address, err := sysfs.GetNetworkAddress(name)
+		if err != nil {
+			return nil, err
+		}
+		mtuStr, err := sysfs.GetNetworkMtu(name)
+		if err != nil {
+			return nil, err
+		}
+		var mtu uint64
+		n, err := fmt.Sscanf(mtuStr, "%d", &mtu)
+		if err != nil || n != 1 {
+			return nil, fmt.Errorf("could not parse mtu from %s for device %s", mtuStr, name)
+		}
+		netInfo := info.NetInfo{
+			Name:       name,
+			MacAddress: strings.TrimSpace(address),
+			Mtu:        mtu,
+		}
+		speed, err := sysfs.GetNetworkSpeed(name)
+		// Some devices don't set speed.
+		if err == nil {
+			var s uint64
+			n, err := fmt.Sscanf(speed, "%d", &s)
+			if err != nil || n != 1 {
+				return nil, fmt.Errorf("could not parse speed from %s for device %s", speed, name)
+			}
+			netInfo.Speed = s
+		}
+		netDevices = append(netDevices, netInfo)
+	}
+	return netDevices, nil
+}
+
 type CacheInfo struct {
 	// size in bytes
 	Size uint64