#!/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 *
from mininet.log import setLogLevel,info
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' )
if self.outputHook:
self.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 )
def handleInt( self, event=None ):
"Handle control-c."
self.node.sendInt()
def sendCmd( self, cmd ):
"Send a command to our node."
text, node = self.text, self.node
if not node.waiting:
node.sendCmd( cmd )
def handleReadable( self, file=None, mask=None, 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.graph = None
self.createWidgets()
self.updateScrollRegions()
self.yview( 'moveto', '1.0' )
def scale( 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 )
fill = 'red'
# Draw scale line
scale.create_line( width - 1, height, width - 1, 0, fill=fill )
# 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, fill=fill )
scale.create_text( 10, ypos, text=str( y ), fill=fill )
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.scale()
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=N+E+W)
scale.grid( row=1, column=0, sticky=N+S+E+W )
graph.grid( row=1, column=1, sticky=N+S+E+W )
ybar.grid( row=1, column=2, sticky=N+S )
xbar.grid( row=2, column=0, columnspan=2, sticky=E+W )
self.rowconfigure( 1, weight=1 )
self.columnconfigure( 1, weight=1 )
# Save for future reference
self.title = title
self.scale = scale
self.graph = graph
return graph
def addBar( self, yval ):
"Add a new bar to our graph."
percent = yval / self.ymax
height = percent * self.gheight
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 ):
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."
m = re.search( r'(\d+) Mbits/sec', output )
if not m:
return
self.updates += 1
self.bw += .001 * float( m.group( 1 ) )
if self.updates >= self.hostCount:
self.graph.addBar( self.bw )
self.bw = 0
self.updates = 0
def setOutputHook( self, fn=None, consoles=None ):
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, 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, set ):
"Select a set of consoles to display."
if self.selected is not None:
self.selected.frame.pack_forget()
self.selected = self.consoles[ set ]
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:
console.node.cmd( 'iperf -sD' )
i = 0
for console in consoles:
i = ( i + 1 ) % count
ip = consoles[ i ].node.IP()
console.sendCmd( 'iperf -t 99999 -i 1 -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 ):
"Stope 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."
for name, value in kwargs.items():
setattr( obj, name, value )
class Object( object ):
"Generic object you can stuff junk into."
def __init__( self, **kwargs ):
assign( self, **kwargs )
if __name__ == '__main__':
setLogLevel( 'info' )
net = TreeNet( depth=2, fanout=4 )
net.start()
app = ConsoleApp( net, width=4 )
app.mainloop()
net.stop()