#!/usr/bin/python

"""
Build a simple network from scratch, using mininet primitives.
This is more complicated than using the higher-level classes,
but it exposes the configuration details and allows customization.

For most tasks, the higher-level API will be preferable.
"""

from mininet.net import init
from mininet.node import Node, KernelSwitch
from mininet.util import createLink
from mininet.log import setLogLevel, info

def scratchNet( cname='controller', cargs='ptcp:' ):
    "Create network from scratch using kernel switch."

    info( "*** Creating nodes\n" )
    controller = Node( 'c0', inNamespace=False )
    switch = Node( 's0', inNamespace=False )
    h0 = Node( 'h0' )
    h1 = Node( 'h1' )

    info( "*** Creating links\n" )
    createLink( node1=h0, node2=switch, port1=0, port2=0 )
    createLink( node1=h1, node2=switch, port1=0, port2=1 )

    info( "*** Configuring hosts\n" )
    h0.setIP( h0.intfs[ 0 ], '192.168.123.1', 24 )
    h1.setIP( h1.intfs[ 0 ], '192.168.123.2', 24 )
    info( str( h0 ) + '\n' )
    info( str( h1 ) + '\n' )

    info( "*** Starting network using kernel datapath\n" )
    controller.cmd( cname + ' ' + cargs + '&' )
    switch.cmd( 'dpctl deldp nl:0' )
    switch.cmd( 'dpctl adddp nl:0' )
    for intf in switch.intfs.values():
        switch.cmd( 'dpctl addif nl:0 ' + intf )
    switch.cmd( 'ofprotocol nl:0 tcp:localhost &' )

    info( "*** Running test\n" )
    h0.cmdPrint( 'ping -c1 ' + h1.IP() )

    info( "*** Stopping network\n" )
    controller.cmd( 'kill %' + cname )
    switch.cmd( 'dpctl deldp nl:0' )
    switch.cmd( 'kill %ofprotocol' )
    switch.deleteIntfs()
    info( '\n' )

if __name__ == '__main__':
    setLogLevel( 'info' )
    info( '*** Scratch network demo (kernel datapath)\n' )
    KernelSwitch.setup()
    init()
    scratchNet()