#!/usr/bin/python
"""
consoles.py: bring up a bunch of miniature consoles on a virtual network
This demo shows how to monitor a set of nodes by using
Node's monitor() and Tkinter's createfilehandler().
We monitor nodes in a couple of ways:
- First, each individual node is monitored, and its output is added
to its console window
- Second, each time a console window gets iperf output, it is parsed
and accumulated. Once we have output for all consoles, a bar is
added to the bandwidth graph.
The consoles also support limited interaction:
- Pressing "return" in a console will send a command to it
- Pressing the console's title button will open up an xterm
Bob Lantz, April 2010
"""
import re
from Tkinter import Frame, Button, Label, Text, Scrollbar, Canvas, Wm, READABLE
from mininet.log import setLogLevel
from mininet.topolib import TreeNet
from mininet.term import makeTerms, cleanUpScreens
from mininet.util import quietRun
class Console( Frame ):
"A simple console on a host."
def __init__( self, parent, net, node, height=10, width=32, title='Node' ):
Frame.__init__( self, parent )
self.net = net
self.node = node
self.prompt = node.name + '# '
self.height, self.width, self.title = height, width, title
# Initialize widget styles
self.buttonStyle = { 'font': 'Monaco 7' }
self.textStyle = {
'font': 'Monaco 7',
'bg': 'black',
'fg': 'green',
'width': self.width,
'height': self.height,
'relief': 'sunken',
'insertbackground': 'green',
'highlightcolor': 'green',
'selectforeground': 'black',
'selectbackground': 'green'
}
# Set up widgets
self.text = self.makeWidgets( )
self.bindEvents()
self.sendCmd( 'export TERM=dumb' )
self.outputHook = None
def makeWidgets( self ):
"Make a label, a text area, and a scroll bar."
def newTerm( net=self.net, node=self.node, title=self.title ):
"Pop up a new terminal window for a node."
net.terms += makeTerms( [ node ], title )
label = Button( self, text=self.node.name, command=newTerm,
**self.buttonStyle )
label.pack( side='top', fill='x' )
text = Text( self, wrap='word', **self.textStyle )
ybar = Scrollbar( self, orient='vertical', width=7,
command=text.yview )
text.configure( yscrollcommand=ybar.set )
text.pack( side='left', expand=True, fill='both' )
ybar.pack( side='right', fill='y' )
return text
def bindEvents( self ):
"Bind keyboard and file events."
# The text widget handles regular key presses, but we
# use special handlers for the following:
self.text.bind( '<Return>', self.handleReturn )
self.text.bind( '<Control-c>', self.handleInt )
self.text.bind( '<KeyPress>', self.handleKey )
# This is not well-documented, but it is the correct
# way to trigger a file event handler from Tk's
# event loop!
self.tk.createfilehandler( self.node.stdout, READABLE,
self.handleReadable )
# We're not a terminal (yet?), so we ignore the following
# control characters other than [\b\n\r]
ignoreChars = re.compile( r'[\x00-\x07\x09\x0b\x0c\x0e-\x1f]+' )
def append( self, text ):
"Append something to our text frame."
text = self.ignoreChars.sub( '', text )
self.text.insert( 'end', text )
self.text.mark_set( 'insert', 'end' )
self.text.see( 'insert' )
outputHook = lambda x, y: True # make pylint happier
if self.outputHook:
outputHook = self.outputHook
outputHook( self, text )
def handleKey( self, event ):
"If it's an interactive command, send it to the node."
char = event.char
if self.node.waiting:
self.node.write( char )
def handleReturn( self, event ):
"Handle a carriage return."
cmd = self.text.get( 'insert linestart', 'insert lineend' )
# Send it immediately, if "interactive" command
if self.node.waiting:
self.node.write( event.char )
return
# Otherwise send the whole line to the shell
pos = cmd.find( self.prompt )
if pos >= 0:
cmd = cmd[ pos + len( self.prompt ): ]
self.sendCmd( cmd )
# Callback ignores event
def handleInt( self, _event=None ):
"Handle control-c."
self.node.sendInt()
def sendCmd( self, cmd ):
"Send a command to our node."
if not self.node.waiting:
self.node.sendCmd( cmd )
def handleReadable( self, _fds, timeoutms=None ):
"Handle file readable event."
data = self.node.monitor( timeoutms )
self.append( data )
if not self.node.waiting:
# Print prompt
self.append( self.prompt )
def waiting( self ):
"Are we waiting for output?"
return self.node.waiting
def waitOutput( self ):
"Wait for any remaining output."
while self.node.waiting:
# A bit of a trade-off here...
self.handleReadable( self, timeoutms=1000)
self.update()
def clear( self ):
"Clear all of our text."
self.text.delete( '1.0', 'end' )
class Graph( Frame ):
"Graph that we can add bars to over time."
def __init__( self, parent=None, bg = 'white', gheight=200, gwidth=500,
barwidth=10, ymax=3.5,):
Frame.__init__( self, parent )
self.bg = bg
self.gheight = gheight
self.gwidth = gwidth
self.barwidth = barwidth
self.ymax = float( ymax )
self.xpos = 0
# Create everything
self.title, self.scale, self.graph = self.createWidgets()
self.updateScrollRegions()
self.yview( 'moveto', '1.0' )
def createScale( self ):
"Create a and return a new canvas with scale markers."
height = float( self.gheight )
width = 25
ymax = self.ymax
scale = Canvas( self, width=width, height=height,
background=self.bg )
opts = { 'fill': 'red' }
# Draw scale line
scale.create_line( width - 1, height, width - 1, 0, **opts )
# Draw ticks and numbers
for y in range( 0, int( ymax + 1 ) ):
ypos = height * (1 - float( y ) / ymax )
scale.create_line( width, ypos, width - 10, ypos, **opts )
scale.create_text( 10, ypos, text=str( y ), **opts )
return scale
def updateScrollRegions( self ):
"Update graph and scale scroll regions."
ofs = 20
height = self.gheight + ofs
self.graph.configure( scrollregion=( 0, -ofs,
self.xpos * self.barwidth, height ) )
self.scale.configure( scrollregion=( 0, -ofs, 0, height ) )
def yview( self, *args ):
"Scroll both scale and graph."
self.graph.yview( *args )
self.scale.yview( *args )
def createWidgets( self ):
"Create initial widget set."
# Objects
title = Label( self, text='Bandwidth (Gb/s)', bg=self.bg )
width = self.gwidth
height = self.gheight
scale = self.createScale()
graph = Canvas( self, width=width, height=height, background=self.bg)
xbar = Scrollbar( self, orient='horizontal', command=graph.xview )
ybar = Scrollbar( self, orient='vertical', command=self.yview )
graph.configure( xscrollcommand=xbar.set, yscrollcommand=ybar.set,
scrollregion=(0, 0, width, height ) )
scale.configure( yscrollcommand=ybar.set )
# Layout
title.grid( row=0, columnspan=3, sticky='new')
scale.grid( row=1, column=0, sticky='nsew' )
graph.grid( row=1, column=1, sticky='nsew' )
ybar.grid( row=1, column=2, sticky='ns' )
xbar.grid( row=2, column=0, columnspan=2, sticky='ew' )
self.rowconfigure( 1, weight=1 )
self.columnconfigure( 1, weight=1 )
return title, scale, graph
def addBar( self, yval ):
"Add a new bar to our graph."
percent = yval / self.ymax
c = self.graph
x0 = self.xpos * self.barwidth
x1 = x0 + self.barwidth
y0 = self.gheight
y1 = ( 1 - percent ) * self.gheight
c.create_rectangle( x0, y0, x1, y1, fill='green' )
self.xpos += 1
self.updateScrollRegions()
self.graph.xview( 'moveto', '1.0' )
def clear( self ):
"Clear graph contents."
self.graph.delete( 'all' )
self.xpos = 0
def test( self ):
"Add a bar for testing purposes."
ms = 1000
if self.xpos < 10:
self.addBar( self.xpos / 10 * self.ymax )
self.after( ms, self.test )
def setTitle( self, text ):
"Set graph title"
self.title.configure( text=text, font='Helvetica 9 bold' )
class ConsoleApp( Frame ):
"Simple Tk consoles for Mininet."
menuStyle = { 'font': 'Geneva 7 bold' }
def __init__( self, net, parent=None, width=4 ):
Frame.__init__( self, parent )
self.top = self.winfo_toplevel()
self.top.title( 'Mininet' )
self.net = net
self.menubar = self.createMenuBar()
cframe = self.cframe = Frame( self )
self.consoles = {} # consoles themselves
titles = {
'hosts': 'Host',
'switches': 'Switch',
'controllers': 'Controller'
}
for name in titles:
nodes = getattr( net, name )
frame, consoles = self.createConsoles(
cframe, nodes, width, titles[ name ] )
self.consoles[ name ] = Object( frame=frame, consoles=consoles )
self.selected = None
self.select( 'hosts' )
self.cframe.pack( expand=True, fill='both' )
cleanUpScreens()
# Close window gracefully
Wm.wm_protocol( self.top, name='WM_DELETE_WINDOW', func=self.quit )
# Initialize graph
graph = Graph( cframe )
self.consoles[ 'graph' ] = Object( frame=graph, consoles=[ graph ] )
self.graph = graph
self.graphVisible = False
self.updates = 0
self.hostCount = len( self.consoles[ 'hosts' ].consoles )
self.bw = 0
self.pack( expand=True, fill='both' )
def updateGraph( self, _console, output ):
"Update our graph."
vals = output.split(',')
if not len(vals) == 9:
return
self.updates += 1
#convert to Gbps
self.bw += int( vals[-1] ) * ( 10 ** -9 )
if self.updates >= self.hostCount:
self.graph.addBar( self.bw )
self.bw = 0
self.updates = 0
def setOutputHook( self, fn=None, consoles=None ):
"Register fn as output hook [on specific consoles.]"
if consoles is None:
consoles = self.consoles[ 'hosts' ].consoles
for console in consoles:
console.outputHook = fn
def createConsoles( self, parent, nodes, width, title ):
"Create a grid of consoles in a frame."
f = Frame( parent )
# Create consoles
consoles = []
index = 0
for node in nodes:
console = Console( f, self.net, node, title=title )
consoles.append( console )
row = index / width
column = index % width
console.grid( row=row, column=column, sticky='nsew' )
index += 1
f.rowconfigure( row, weight=1 )
f.columnconfigure( column, weight=1 )
return f, consoles
def select( self, groupName ):
"Select a group of consoles to display."
if self.selected is not None:
self.selected.frame.pack_forget()
self.selected = self.consoles[ groupName ]
self.selected.frame.pack( expand=True, fill='both' )
def createMenuBar( self ):
"Create and return a menu (really button) bar."
f = Frame( self )
buttons = [
( 'Hosts', lambda: self.select( 'hosts' ) ),
( 'Switches', lambda: self.select( 'switches' ) ),
( 'Controllers', lambda: self.select( 'controllers' ) ),
( 'Graph', lambda: self.select( 'graph' ) ),
( 'Ping', self.ping ),
( 'Iperf', self.iperf ),
( 'Interrupt', self.stop ),
( 'Clear', self.clear ),
( 'Quit', self.quit )
]
for name, cmd in buttons:
b = Button( f, text=name, command=cmd, **self.menuStyle )
b.pack( side='left' )
f.pack( padx=4, pady=4, fill='x' )
return f
def clear( self ):
"Clear selection."
for console in self.selected.consoles:
console.clear()
def waiting( self, consoles=None ):
"Are any of our hosts waiting for output?"
if consoles is None:
consoles = self.consoles[ 'hosts' ].consoles
for console in consoles:
if console.waiting():
return True
return False
def ping( self ):
"Tell each host to ping the next one."
consoles = self.consoles[ 'hosts' ].consoles
if self.waiting( consoles ):
return
count = len( consoles )
i = 0
for console in consoles:
i = ( i + 1 ) % count
ip = consoles[ i ].node.IP()
console.sendCmd( 'ping ' + ip )
def iperf( self ):
"Tell each host to iperf to the next one."
consoles = self.consoles[ 'hosts' ].consoles
if self.waiting( consoles ):
return
count = len( consoles )
self.setOutputHook( self.updateGraph )
for console in consoles:
#sometimes iperf -sD doesn't return, so we run it in the background instead
console.node.cmd( 'iperf -s &' )
i = 0
for console in consoles:
i = ( i + 1 ) % count
ip = consoles[ i ].node.IP()
console.sendCmd( 'iperf -t 99999 -i 1 -y c -c ' + ip )
def stop( self, wait=True ):
"Interrupt all hosts."
consoles = self.consoles[ 'hosts' ].consoles
for console in consoles:
console.handleInt()
if wait:
for console in consoles:
console.waitOutput()
self.setOutputHook( None )
# Shut down any iperfs that might still be running
quietRun( 'killall -9 iperf' )
def quit( self ):
"Stop everything and quit."
self.stop( wait=False)
Frame.quit( self )
# Make it easier to construct and assign objects
def assign( obj, **kwargs ):
"Set a bunch of fields in an object."
obj.__dict__.update( kwargs )
class Object( object ):
"Generic object you can stuff junk into."
def __init__( self, **kwargs ):
assign( self, **kwargs )
if __name__ == '__main__':
setLogLevel( 'info' )
network = TreeNet( depth=2, fanout=4 )
network.start()
app = ConsoleApp( network, width=4 )
app.mainloop()
network.stop()