Breakup the system plugin

plugins/system/net.go

@@ -0,0 +1,88 @@
+package system
+
+import (
+	"fmt"
+	"net"
+
+	"github.com/influxdb/tivan/plugins"
+)
+
+type NetIOStats struct {
+	ps PS
+
+	Interfaces []string
+}
+
+func (_ *NetIOStats) Description() string {
+	return "Read metrics about network interface usage"
+}
+
+var netSampleConfig = `
+# By default, tivan gathers stats from any up interface (excluding loopback)
+# Setting interfaces will tell it to gather these explicit interfaces,
+# regardless of status.
+#
+# interfaces = ["eth0", ... ]
+`
+
+func (_ *NetIOStats) SampleConfig() string {
+	return netSampleConfig
+}
+
+func (s *NetIOStats) Gather(acc plugins.Accumulator) error {
+	netio, err := s.ps.NetIO()
+	if err != nil {
+		return fmt.Errorf("error getting net io info: %s", err)
+	}
+
+	for _, io := range netio {
+		if len(s.Interfaces) != 0 {
+			var found bool
+
+			for _, name := range s.Interfaces {
+				if name == io.Name {
+					found = true
+					break
+				}
+			}
+
+			if !found {
+				continue
+			}
+		} else {
+			iface, err := net.InterfaceByName(io.Name)
+			if err != nil {
+				continue
+			}
+
+			if iface.Flags&net.FlagLoopback == net.FlagLoopback {
+				continue
+			}
+
+			if iface.Flags&net.FlagUp == 0 {
+				continue
+			}
+		}
+
+		tags := map[string]string{
+			"interface": io.Name,
+		}
+
+		acc.Add("bytes_sent", io.BytesSent, tags)
+		acc.Add("bytes_recv", io.BytesRecv, tags)
+		acc.Add("packets_sent", io.PacketsSent, tags)
+		acc.Add("packets_recv", io.PacketsRecv, tags)
+		acc.Add("err_in", io.Errin, tags)
+		acc.Add("err_out", io.Errout, tags)
+		acc.Add("drop_in", io.Dropin, tags)
+		acc.Add("drop_out", io.Dropout, tags)
+	}
+
+	return nil
+}
+
+func init() {
+	plugins.Add("net", func() plugins.Plugin {
+		return &NetIOStats{ps: &systemPS{}}
+	})
+}