golib/network

Network package

This package is useful to retrieve network interface information and counter.

The information available are :

• name of the interface (cannot be empty)
• physical address (or hardware address) (can be empty for example virtual ip or bridge)
• MTU (Maximu Transmission Unit) is the maximum size of packets could be transmit
• Addr is the list of all network address (can be empty)
• Index is the index for the current interface into the list all interface for current os
• Flags are capabilities supported by the interface. You can find const for all flags available in golang/x/net package :
  • FlagUp: interface is up
  • FlagBroadcast: interface supports broadcast access capability
  • FlagLoopback: interface is a loopback interface
  • FlagPointToPoint: interface belongs to a point-to-point link
  • FlagMulticast: interface supports multicast access capability

Example of implement

You can get all interface with filter.

In this example we will search all interface who's have physical address and having at least on address =and match the list of flags composed here with only FlagUp :

// GetAllInterfaces(context.Context, onlyPhysical, hasAddr bool, atLeastMTU int, withFlags ...net.Flags)
list, err := network.GetAllInterfaces(context.Background(), true, true, 0, net.FlagUp)

You can also retrieve on interface based on his name or his phyisical address :

//NewInterface(context.Context, name, physical string)
i, e := NewInterface(context.Context, "eth0", "") 

When you have you interface variable, you can use it to print for example the counter of received data.

The available statistics are grouped by way : In or Out In each group, the stats are :

• StatBytes : Traffic in Bytes
• StatPackets : Number of Packets
• StatFifo : Number of packet in FIFO
• StatDrop : Number of packet dropped
• StatErr : Number of packet in Error

Stats are given as map[Stats]Number :

• Stats is a self defined to map constant with a statement.
• Number are still self defined type to allow formatting.
• Bytes is closed similar to Number but with different unit

This translation between bytes and number included into each type :

• Number.AsBytes
• Bytes.AsNumber

You can also convert this type as uint64 or as float64.

Now, we have all information to understand this example who's print all stat of sending traffic with unit :

		fmt.Print("\tOut: \n")
 		l = i.GetStatOut()
 		for _, k := range network.ListStatsSort() {
 			s := network.Stats(k)
 			if v, ok := l[s]; ok {
 				fmt.Printf("\t\t%s\n", s.FormatLabelUnitPadded(v))
 			} else {
 				fmt.Printf("\t\t%s\n", s.FormatLabelUnitPadded(0))
 			}
 		}

Example

You can find an example in test/test-network

There result of this example is like this :

iface 'eth0' [00:15:5d:66:60:dd] :
        Flags: up broadcast multicast
        Addrs: {"addr":"172.25.59.95/20"} {"addr":"fe80::215:5dff:fe66:60dd/64"}
        In:
                Traffic:   27.33 GB
                Packets:   20 M
                Fifo:       0
                Drop:       0
                Error:      0
        Out:
                Traffic:   28.03 GB
                Packets: 1118 K
                Fifo:       0
                Drop:       0
                Error:      0