7 files changed, 72 insertions, 16 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f5ab4fe..eca02bd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,9 +2,12 @@
 
 ### **Breaking changes**
 
+* The netdev collector CLI argument `--collector.netdev.ignored-devices` was renamed to `--collector.netdev.device-blacklist` in order to conform with the systemd collector. #1279
+
+
 ### Changes
 
-* [CHANGE]
+* [CHANGE] Add `--collector.netdev.device-whitelist`. #1279
 * [FEATURE]
 * [ENHANCEMENT]
 * [BUGFIX] Fix incorrect sysctl call in BSD meminfo collector, resulting in broken swap metrics on FreeBSD #1345
diff --git a/collector/netdev_bsd.go b/collector/netdev_bsd.go
index d846daf..18eca22 100644
--- a/collector/netdev_bsd.go
+++ b/collector/netdev_bsd.go
@@ -34,7 +34,7 @@ import (
 */
 import "C"
 
-func getNetDevStats(ignore *regexp.Regexp) (map[string]map[string]string, error) {
+func getNetDevStats(ignore *regexp.Regexp, accept *regexp.Regexp) (map[string]map[string]string, error) {
         netDev := map[string]map[string]string{}
 
         var ifap, ifa *C.struct_ifaddrs
@@ -46,7 +46,11 @@ func getNetDevStats(ignore *regexp.Regexp) (map[string]map[string]string, error)
         for ifa = ifap; ifa != nil; ifa = ifa.ifa_next {
                 if ifa.ifa_addr.sa_family == C.AF_LINK {
                         dev := C.GoString(ifa.ifa_name)
-                        if ignore.MatchString(dev) {
+                        if ignore != nil && ignore.MatchString(dev) {
+                                log.Debugf("Ignoring device: %s", dev)
+                                continue
+                        }
+                        if accept != nil && !accept.MatchString(dev) {
                                 log.Debugf("Ignoring device: %s", dev)
                                 continue
                         }
diff --git a/collector/netdev_common.go b/collector/netdev_common.go
index 9fa3cd2..0c11023 100644
--- a/collector/netdev_common.go
+++ b/collector/netdev_common.go
@@ -17,6 +17,7 @@
 package collector
 
 import (
+        "errors"
         "fmt"
         "regexp"
         "strconv"
@@ -26,12 +27,14 @@ import (
 )
 
 var (
-        netdevIgnoredDevices = kingpin.Flag("collector.netdev.ignored-devices", "Regexp of net devices to ignore for netdev collector.").Default("^$").String()
+        netdevIgnoredDevices = kingpin.Flag("collector.netdev.device-blacklist", "Regexp of net devices to blacklist (mutually exclusive to device-whitelist).").String()
+        netdevAcceptDevices  = kingpin.Flag("collector.netdev.device-whitelist", "Regexp of net devices to whitelist (mutually exclusive to device-blacklist).").String()
 )
 
 type netDevCollector struct {
         subsystem             string
         ignoredDevicesPattern *regexp.Regexp
+        acceptDevicesPattern  *regexp.Regexp
         metricDescs           map[string]*prometheus.Desc
 }
 
@@ -41,16 +44,30 @@ func init() {
 
 // NewNetDevCollector returns a new Collector exposing network device stats.
 func NewNetDevCollector() (Collector, error) {
-        pattern := regexp.MustCompile(*netdevIgnoredDevices)
+        if *netdevIgnoredDevices != "" && *netdevAcceptDevices != "" {
+                return nil, errors.New("device-blacklist & accept-devices are mutually exclusive")
+        }
+
+        var ignorePattern *regexp.Regexp = nil
+        if *netdevIgnoredDevices != "" {
+                ignorePattern = regexp.MustCompile(*netdevIgnoredDevices)
+        }
+
+        var acceptPattern *regexp.Regexp = nil
+        if *netdevAcceptDevices != "" {
+                acceptPattern = regexp.MustCompile(*netdevAcceptDevices)
+        }
+
         return &netDevCollector{
                 subsystem:             "network",
-                ignoredDevicesPattern: pattern,
+                ignoredDevicesPattern: ignorePattern,
+                acceptDevicesPattern:  acceptPattern,
                 metricDescs:           map[string]*prometheus.Desc{},
         }, nil
 }
 
 func (c *netDevCollector) Update(ch chan<- prometheus.Metric) error {
-        netDev, err := getNetDevStats(c.ignoredDevicesPattern)
+        netDev, err := getNetDevStats(c.ignoredDevicesPattern, c.acceptDevicesPattern)
         if err != nil {
                 return fmt.Errorf("couldn't get netstats: %s", err)
         }
diff --git a/collector/netdev_darwin.go b/collector/netdev_darwin.go
index b02ed40..c07e7fa 100644
--- a/collector/netdev_darwin.go
+++ b/collector/netdev_darwin.go
@@ -27,7 +27,7 @@ import (
         "golang.org/x/sys/unix"
 )
 
-func getNetDevStats(ignore *regexp.Regexp) (map[string]map[string]string, error) {
+func getNetDevStats(ignore *regexp.Regexp, accept *regexp.Regexp) (map[string]map[string]string, error) {
         netDev := map[string]map[string]string{}
 
         ifs, err := net.Interfaces()
@@ -46,6 +46,10 @@ func getNetDevStats(ignore *regexp.Regexp) (map[string]map[string]string, error)
                         log.Debugf("Ignoring device: %s", iface.Name)
                         continue
                 }
+                if accept != nil && !accept.MatchString(iface.Name) {
+                        log.Debugf("Ignoring device: %s", iface.Name)
+                        continue
+                }
 
                 devStats := map[string]string{}
                 devStats["receive_packets"] = strconv.FormatUint(ifaceData.Data.Ipackets, 10)
diff --git a/collector/netdev_linux.go b/collector/netdev_linux.go
index 4ea09a3..a5c6163 100644
--- a/collector/netdev_linux.go
+++ b/collector/netdev_linux.go
@@ -31,17 +31,17 @@ var (
         procNetDevFieldSep    = regexp.MustCompile(` +`)
 )
 
-func getNetDevStats(ignore *regexp.Regexp) (map[string]map[string]string, error) {
+func getNetDevStats(ignore *regexp.Regexp, accept *regexp.Regexp) (map[string]map[string]string, error) {
         file, err := os.Open(procFilePath("net/dev"))
         if err != nil {
                 return nil, err
         }
         defer file.Close()
 
-        return parseNetDevStats(file, ignore)
+        return parseNetDevStats(file, ignore, accept)
 }
 
-func parseNetDevStats(r io.Reader, ignore *regexp.Regexp) (map[string]map[string]string, error) {
+func parseNetDevStats(r io.Reader, ignore *regexp.Regexp, accept *regexp.Regexp) (map[string]map[string]string, error) {
         scanner := bufio.NewScanner(r)
         scanner.Scan() // skip first header
         scanner.Scan()
@@ -64,7 +64,11 @@ func parseNetDevStats(r io.Reader, ignore *regexp.Regexp) (map[string]map[string
                 }
 
                 dev := parts[1]
-                if ignore.MatchString(dev) {
+                if ignore != nil && ignore.MatchString(dev) {
+                        log.Debugf("Ignoring device: %s", dev)
+                        continue
+                }
+                if accept != nil && !accept.MatchString(dev) {
                         log.Debugf("Ignoring device: %s", dev)
                         continue
                 }
diff --git a/collector/netdev_linux_test.go b/collector/netdev_linux_test.go
index 7228ae2..163c87f 100644
--- a/collector/netdev_linux_test.go
+++ b/collector/netdev_linux_test.go
@@ -19,14 +19,14 @@ import (
         "testing"
 )
 
-func TestNetDevStats(t *testing.T) {
+func TestNetDevStatsIgnore(t *testing.T) {
         file, err := os.Open("fixtures/proc/net/dev")
         if err != nil {
                 t.Fatal(err)
         }
         defer file.Close()
 
-        netStats, err := parseNetDevStats(file, regexp.MustCompile("^veth"))
+        netStats, err := parseNetDevStats(file, regexp.MustCompile("^veth"), nil)
         if err != nil {
                 t.Fatal(err)
         }
@@ -59,3 +59,23 @@ func TestNetDevStats(t *testing.T) {
                 t.Error("want fixture interface 💩0 to exist, but it does not")
         }
 }
+
+func TestNetDevStatsAccept(t *testing.T) {
+        file, err := os.Open("fixtures/proc/net/dev")
+        if err != nil {
+                t.Fatal(err)
+        }
+        defer file.Close()
+
+        netStats, err := parseNetDevStats(file, nil, regexp.MustCompile("^💩0$"))
+        if err != nil {
+                t.Fatal(err)
+        }
+
+        if want, got := 1, len(netStats); want != got {
+                t.Errorf("want count of devices to be %d, got %d", want, got)
+        }
+        if want, got := "72", netStats["💩0"]["receive_multicast"]; want != got {
+                t.Error("want fixture interface 💩0 to exist, but it does not")
+        }
+}
diff --git a/collector/netdev_openbsd.go b/collector/netdev_openbsd.go
index 0e9c900..b080cbc 100644
--- a/collector/netdev_openbsd.go
+++ b/collector/netdev_openbsd.go
@@ -31,7 +31,7 @@ import (
 */
 import "C"
 
-func getNetDevStats(ignore *regexp.Regexp) (map[string]map[string]string, error) {
+func getNetDevStats(ignore *regexp.Regexp, accept *regexp.Regexp) (map[string]map[string]string, error) {
         netDev := map[string]map[string]string{}
 
         var ifap, ifa *C.struct_ifaddrs
@@ -43,7 +43,11 @@ func getNetDevStats(ignore *regexp.Regexp) (map[string]map[string]string, error)
         for ifa = ifap; ifa != nil; ifa = ifa.ifa_next {
                 if ifa.ifa_addr.sa_family == C.AF_LINK {
                         dev := C.GoString(ifa.ifa_name)
-                        if ignore.MatchString(dev) {
+                        if ignore != nil && ignore.MatchString(dev) {
+                                log.Debugf("Ignoring device: %s", dev)
+                                continue
+                        }
+                        if accept != nil && !accept.MatchString(dev) {
                                 log.Debugf("Ignoring device: %s", dev)
                                 continue
                         }