only run ifconfig/netstat if necessary, add some tests

pull/254/head
Bruno Clermont 9 years ago
parent 145e48efdb
commit 3f96312057

@ -4,108 +4,248 @@ package net
import (
"errors"
"fmt"
"os/exec"
"regexp"
"strconv"
"strings"
)
// example of `netstat -ibdnWI lo0` output on yosemite
var (
errNetstatHeader = errors.New("Can't parse header of netstat output")
netstatLinkRegexp = regexp.MustCompile(`^<Link#(\d+)>$`)
)
const endOfLine = "\n"
func parseNetstatLine(line string) (stat *IOCountersStat, linkId *uint, err error) {
var (
numericValue uint64
columns = strings.Fields(line)
)
if columns[0] == "Name" {
err = errNetstatHeader
return
}
// try to extract the numeric value from <Link#123>
if subMatch := netstatLinkRegexp.FindStringSubmatch(columns[2]); len(subMatch) == 2 {
numericValue, err = strconv.ParseUint(subMatch[1], 10, 64)
if err != nil {
return
}
linkIdUint := uint(numericValue)
linkId = &linkIdUint
}
base := 1
numberColumns := len(columns)
// sometimes Address is ommitted
if numberColumns < 12 {
base = 0
}
if numberColumns < 11 || numberColumns > 13 {
err = fmt.Errorf("Line %q do have an invalid number of columns %d", line, numberColumns)
return
}
parsed := make([]uint64, 0, 7)
vv := []string{
columns[base+3], // Ipkts == PacketsRecv
columns[base+4], // Ierrs == Errin
columns[base+5], // Ibytes == BytesRecv
columns[base+6], // Opkts == PacketsSent
columns[base+7], // Oerrs == Errout
columns[base+8], // Obytes == BytesSent
}
if len(columns) == 12 {
vv = append(vv, columns[base+10])
}
for _, target := range vv {
if target == "-" {
parsed = append(parsed, 0)
continue
}
if numericValue, err = strconv.ParseUint(target, 10, 64); err != nil {
return
}
parsed = append(parsed, numericValue)
}
stat = &IOCountersStat{
Name: strings.Trim(columns[0], "*"), // remove the * that sometimes is on right on interface
PacketsRecv: parsed[0],
Errin: parsed[1],
BytesRecv: parsed[2],
PacketsSent: parsed[3],
Errout: parsed[4],
BytesSent: parsed[5],
}
if len(parsed) == 7 {
stat.Dropout = parsed[6]
}
return
}
type netstatInterface struct {
linkId *uint
stat *IOCountersStat
}
func parseNetstatOutput(output string) ([]netstatInterface, error) {
var (
err error
lines = strings.Split(strings.Trim(output, endOfLine), endOfLine)
)
// number of interfaces is number of lines less one for the header
numberInterfaces := len(lines) - 1
interfaces := make([]netstatInterface, numberInterfaces)
// no output beside header
if numberInterfaces == 0 {
return interfaces, nil
}
for index := 0; index < numberInterfaces; index++ {
nsIface := netstatInterface{}
if nsIface.stat, nsIface.linkId, err = parseNetstatLine(lines[index+1]); err != nil {
return nil, err
}
interfaces[index] = nsIface
}
return interfaces, nil
}
// map that hold the name of a network interface and the number of usage
type mapInterfaceNameUsage map[string]uint
func newMapInterfaceNameUsage(ifaces []netstatInterface) mapInterfaceNameUsage {
output := make(mapInterfaceNameUsage)
for index := range ifaces {
if ifaces[index].linkId != nil {
ifaceName := ifaces[index].stat.Name
usage, ok := output[ifaceName]
if ok {
output[ifaceName] = usage + 1
} else {
output[ifaceName] = 1
}
}
}
return output
}
func (min mapInterfaceNameUsage) isTruncated() bool {
for _, usage := range min {
if usage > 1 {
return true
}
}
return false
}
func (min mapInterfaceNameUsage) notTruncated() []string {
output := make([]string, 0)
for ifaceName, usage := range min {
if usage == 1 {
output = append(output, ifaceName)
}
}
return output
}
// example of `netstat -ibdnW` output on yosemite
// Name Mtu Network Address Ipkts Ierrs Ibytes Opkts Oerrs Obytes Coll Drop
// lo0 16384 <Link#1> 869107 0 169411755 869107 0 169411755 0 0
// lo0 16384 ::1/128 ::1 869107 - 169411755 869107 - 169411755 - -
// lo0 16384 127 127.0.0.1 869107 - 169411755 869107 - 169411755 - -
func IOCounters(pernic bool) ([]IOCountersStat, error) {
const endOfLine = "\n"
// example of `ifconfig -l` output on yosemite:
// lo0 gif0 stf0 en0 p2p0 awdl0
ifconfig, err := exec.LookPath("/sbin/ifconfig")
var (
ret []IOCountersStat
retIndex int
)
netstat, err := exec.LookPath("/usr/sbin/netstat")
if err != nil {
return nil, err
}
netstat, err := exec.LookPath("/usr/sbin/netstat")
// try to get all interface metrics, and hope there won't be any truncated
out, err := invoke.Command(netstat, "-ibdnW")
if err != nil {
return nil, err
}
// list all interfaces
out, err := invoke.Command(ifconfig, "-l")
nsInterfaces, err := parseNetstatOutput(string(out))
if err != nil {
return nil, err
}
interfaces := strings.Fields(strings.TrimRight(string(out), endOfLine))
ret := make([]IOCountersStat, 0)
// extract metrics for all interfaces
for _, interfaceName := range interfaces {
if out, err = invoke.Command(netstat, "-ibdnWI" + interfaceName); err != nil {
return nil, err
}
lines := strings.Split(string(out), endOfLine)
if len(lines) <= 1 {
// invalid output
continue
}
ifaceUsage := newMapInterfaceNameUsage(nsInterfaces)
notTruncated := ifaceUsage.notTruncated()
ret = make([]IOCountersStat, len(notTruncated))
if len(lines[1]) == 0 {
// interface had been removed since `ifconfig -l` had been executed
continue
}
// only the first output is fine
values := strings.Fields(lines[1])
base := 1
// sometimes Address is ommitted
if len(values) < 12 {
base = 0
if !ifaceUsage.isTruncated() {
// no truncated interface name, return stats of all interface with <Link#...>
for index := range nsInterfaces {
if nsInterfaces[index].linkId != nil {
ret[retIndex] = *nsInterfaces[index].stat
retIndex++
}
}
parsed := make([]uint64, 0, 7)
vv := []string{
values[base+3], // Ipkts == PacketsRecv
values[base+4], // Ierrs == Errin
values[base+5], // Ibytes == BytesRecv
values[base+6], // Opkts == PacketsSent
values[base+7], // Oerrs == Errout
values[base+8], // Obytes == BytesSent
} else {
// duplicated interface, list all interfaces
ifconfig, err := exec.LookPath("/sbin/ifconfig")
if err != nil {
return nil, err
}
if len(values) == 12 {
vv = append(vv, values[base+10])
if out, err = invoke.Command(ifconfig, "-l"); err != nil {
return nil, err
}
interfaceNames := strings.Fields(strings.TrimRight(string(out), endOfLine))
for _, target := range vv {
if target == "-" {
parsed = append(parsed, 0)
continue
// for each of the interface name, run netstat if we don't have any stats yet
for _, interfaceName := range interfaceNames {
truncated := true
for index := range nsInterfaces {
if nsInterfaces[index].linkId != nil && nsInterfaces[index].stat.Name == interfaceName {
// handle the non truncated name to avoid execute netstat for them again
ret[retIndex] = *nsInterfaces[index].stat
retIndex++
truncated = false
break
}
}
t, err := strconv.ParseUint(target, 10, 64)
if err != nil {
return nil, err
if truncated {
// run netstat with -I$ifacename
if out, err = invoke.Command(netstat, "-ibdnWI" + interfaceName);err != nil {
return nil, err
}
parsedIfaces, err := parseNetstatOutput(string(out))
if err != nil {
return nil, err
}
if len(parsedIfaces) == 0 {
// interface had been removed since `ifconfig -l` had been executed
continue
}
for index := range parsedIfaces {
if parsedIfaces[index].linkId != nil {
ret = append(ret, *parsedIfaces[index].stat)
break
}
}
}
parsed = append(parsed, t)
}
n := IOCountersStat{
Name: interfaceName,
PacketsRecv: parsed[0],
Errin: parsed[1],
BytesRecv: parsed[2],
PacketsSent: parsed[3],
Errout: parsed[4],
BytesSent: parsed[5],
}
if len(parsed) == 7 {
n.Dropout = parsed[6]
}
ret = append(ret, n)
}
if pernic == false {
return getIOCountersAll(ret)
}
return ret, nil
}

@ -0,0 +1,140 @@
package net
import (
"testing"
assert "github.com/stretchr/testify/require"
)
const (
netstatTruncated = `Name Mtu Network Address Ipkts Ierrs Ibytes Opkts Oerrs Obytes Coll Drop
lo0 16384 <Link#1> 31241 0 3769823 31241 0 3769823 0 0
lo0 16384 ::1/128 ::1 31241 - 3769823 31241 - 3769823 - -
lo0 16384 127 127.0.0.1 31241 - 3769823 31241 - 3769823 - -
lo0 16384 fe80::1%lo0 fe80:1::1 31241 - 3769823 31241 - 3769823 - -
gif0* 1280 <Link#2> 0 0 0 0 0 0 0 0
stf0* 1280 <Link#3> 0 0 0 0 0 0 0 0
utun8 1500 <Link#88> 286 0 27175 0 0 0 0 0
utun8 1500 <Link#90> 286 0 29554 0 0 0 0 0
utun8 1500 <Link#92> 286 0 29244 0 0 0 0 0
utun8 1500 <Link#93> 286 0 28267 0 0 0 0 0
utun8 1500 <Link#95> 286 0 28593 0 0 0 0 0`
netstatNotTruncated = `Name Mtu Network Address Ipkts Ierrs Ibytes Opkts Oerrs Obytes Coll Drop
lo0 16384 <Link#1> 27190978 0 12824763793 27190978 0 12824763793 0 0
lo0 16384 ::1/128 ::1 27190978 - 12824763793 27190978 - 12824763793 - -
lo0 16384 127 127.0.0.1 27190978 - 12824763793 27190978 - 12824763793 - -
lo0 16384 fe80::1%lo0 fe80:1::1 27190978 - 12824763793 27190978 - 12824763793 - -
gif0* 1280 <Link#2> 0 0 0 0 0 0 0 0
stf0* 1280 <Link#3> 0 0 0 0 0 0 0 0
en0 1500 <Link#4> a8:66:7f:dd:ee:ff 5708989 0 7295722068 3494252 0 379533492 0 230
en0 1500 fe80::aa66: fe80:4::aa66:7fff 5708989 - 7295722068 3494252 - 379533492 - -`
)
func TestparseNetstatLineHeader(t *testing.T) {
stat, linkIkd, err := parseNetstatLine(`Name Mtu Network Address Ipkts Ierrs Ibytes Opkts Oerrs Obytes Coll Drop`)
assert.Nil(t, linkIkd)
assert.Nil(t, stat)
assert.Error(t, err)
assert.Equal(t, errNetstatHeader, err)
}
func assertLoopbackStat(t *testing.T, err error, stat *IOCountersStat) {
assert.NoError(t, err)
assert.Equal(t, 869107, stat.PacketsRecv)
assert.Equal(t, 0, stat.Errin)
assert.Equal(t, 169411755, stat.BytesRecv)
assert.Equal(t,869108, stat.PacketsSent)
assert.Equal(t, 1, stat.Errout)
assert.Equal(t, 169411756, stat.BytesSent)
}
func TestparseNetstatLineLink(t *testing.T) {
stat, linkId, err := parseNetstatLine(
`lo0 16384 <Link#1> 869107 0 169411755 869108 1 169411756 0 0`,
)
assertLoopbackStat(t, err, stat)
assert.NotNil(t, linkId)
assert.Equal(t, uint(1), *linkId)
}
func TestparseNetstatLineIPv6(t *testing.T) {
stat, linkId, err := parseNetstatLine(
`lo0 16384 ::1/128 ::1 869107 - 169411755 869108 1 169411756 - -`,
)
assertLoopbackStat(t, err, stat)
assert.Nil(t, linkId)
}
func TestparseNetstatLineIPv4(t *testing.T) {
stat, linkId, err := parseNetstatLine(
`lo0 16384 127 127.0.0.1 869107 - 169411755 869108 1 169411756 - -`,
)
assertLoopbackStat(t, err, stat)
assert.Nil(t, linkId)
}
func TestParseNetstatOutput(t *testing.T) {
nsInterfaces, err := parseNetstatOutput(netstatNotTruncated)
assert.NoError(t, err)
assert.Len(t, nsInterfaces, 8)
for index := range nsInterfaces {
assert.NotNil(t, nsInterfaces[index].stat, "Index %d", index)
}
assert.NotNil(t, nsInterfaces[0].linkId)
assert.Equal(t, uint(1), *nsInterfaces[0].linkId)
assert.Nil(t, nsInterfaces[1].linkId)
assert.Nil(t, nsInterfaces[2].linkId)
assert.Nil(t, nsInterfaces[3].linkId)
assert.NotNil(t, nsInterfaces[4].linkId)
assert.Equal(t, uint(2), *nsInterfaces[4].linkId)
assert.NotNil(t, nsInterfaces[5].linkId)
assert.Equal(t, uint(3), *nsInterfaces[5].linkId)
assert.NotNil(t, nsInterfaces[6].linkId)
assert.Equal(t, uint(4), *nsInterfaces[6].linkId)
assert.Nil(t, nsInterfaces[7].linkId)
mapUsage := newMapInterfaceNameUsage(nsInterfaces)
assert.False(t, mapUsage.isTruncated())
assert.Len(t, mapUsage.notTruncated(), 4)
}
func TestParseNetstatTruncated(t *testing.T) {
nsInterfaces, err := parseNetstatOutput(netstatTruncated)
assert.NoError(t, err)
assert.Len(t, nsInterfaces, 11)
for index := range nsInterfaces {
assert.NotNil(t, nsInterfaces[index].stat, "Index %d", index)
}
const truncatedIface = "utun8"
assert.NotNil(t, nsInterfaces[6].linkId)
assert.Equal(t, uint(88), *nsInterfaces[6].linkId)
assert.Equal(t, truncatedIface, nsInterfaces[6].stat.Name)
assert.NotNil(t, nsInterfaces[7].linkId)
assert.Equal(t,uint(90), *nsInterfaces[7].linkId)
assert.Equal(t, truncatedIface, nsInterfaces[7].stat.Name)
assert.NotNil(t, nsInterfaces[8].linkId)
assert.Equal(t, uint(92), *nsInterfaces[8].linkId )
assert.Equal(t, truncatedIface, nsInterfaces[8].stat.Name)
assert.NotNil(t, nsInterfaces[9].linkId)
assert.Equal(t, uint(93), *nsInterfaces[9].linkId )
assert.Equal(t, truncatedIface, nsInterfaces[9].stat.Name)
assert.NotNil(t, nsInterfaces[10].linkId)
assert.Equal(t, uint(95), *nsInterfaces[10].linkId )
assert.Equal(t, truncatedIface, nsInterfaces[10].stat.Name)
mapUsage := newMapInterfaceNameUsage(nsInterfaces)
assert.True(t, mapUsage.isTruncated())
assert.Equal(t, 3, len(mapUsage.notTruncated()), "en0, gif0 and stf0")
}
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