Main Program¶
This is an example simulator that is written using the python wx bindings. Although it currently does not have a frontend for modifying the context values, it does allow one to expose N virtual modbus devices to a network which is useful for testing data center monitoring tools.
Note
The virtual networking code will only work on linux
#!/usr/bin/env python
'''
Note that this is not finished
'''
#---------------------------------------------------------------------------#
# System
#---------------------------------------------------------------------------#
import os
import getpass
import pickle
from threading import Thread
#---------------------------------------------------------------------------#
# For Gui
#---------------------------------------------------------------------------#
import wx
from twisted.internet import wxreactor
wxreactor.install()
#---------------------------------------------------------------------------#
# SNMP Simulator
#---------------------------------------------------------------------------#
from twisted.internet import reactor
from twisted.internet import error as twisted_error
from pymodbus.server.async import ModbusServerFactory
from pymodbus.datastore import ModbusServerContext,ModbusSlaveContext
#--------------------------------------------------------------------------#
# Logging
#--------------------------------------------------------------------------#
import logging
log = logging.getLogger("pymodbus")
#---------------------------------------------------------------------------#
# Application Error
#---------------------------------------------------------------------------#
class ConfigurationException(Exception):
''' Exception for configuration error '''
pass
#---------------------------------------------------------------------------#
# Extra Global Functions
#---------------------------------------------------------------------------#
# These are extra helper functions that don't belong in a class
#---------------------------------------------------------------------------#
def root_test():
''' Simple test to see if we are running as root '''
return getpass.getuser() == "root"
#---------------------------------------------------------------------------#
# Simulator Class
#---------------------------------------------------------------------------#
class Simulator(object):
'''
Class used to parse configuration file and create and modbus
datastore.
The format of the configuration file is actually just a
python pickle, which is a compressed memory dump from
the scraper.
'''
def __init__(self, config):
'''
Trys to load a configuration file, lets the file not
found exception fall through
@param config The pickled datastore
'''
try:
self.file = open(config, "r")
except Exception:
raise ConfigurationException("File not found %s" % config)
def _parse(self):
''' Parses the config file and creates a server context '''
try:
handle = pickle.load(self.file)
dsd = handle['di']
csd = handle['ci']
hsd = handle['hr']
isd = handle['ir']
except KeyError:
raise ConfigurationException("Invalid Configuration")
slave = ModbusSlaveContext(d=dsd, c=csd, h=hsd, i=isd)
return ModbusServerContext(slaves=slave)
def _simulator(self):
''' Starts the snmp simulator '''
ports = [502]+range(20000,25000)
for port in ports:
try:
reactor.listenTCP(port, ModbusServerFactory(self._parse()))
print 'listening on port', port
return port
except twisted_error.CannotListenError:
pass
def run(self):
''' Used to run the simulator '''
reactor.callWhenRunning(self._simulator)
#---------------------------------------------------------------------------#
# Network reset thread
#---------------------------------------------------------------------------#
# This is linux only, maybe I should make a base class that can be filled
# in for linux(debian/redhat)/windows/nix
#---------------------------------------------------------------------------#
class NetworkReset(Thread):
'''
This class is simply a daemon that is spun off at the end of the
program to call the network restart function (an easy way to
remove all the virtual interfaces)
'''
def __init__(self):
''' Initializes a new instance of the network reset thread '''
Thread.__init__(self)
self.setDaemon(True)
def run(self):
''' Run the network reset '''
os.system("/etc/init.d/networking restart")
#---------------------------------------------------------------------------#
# Main Gui Class
#---------------------------------------------------------------------------#
class SimulatorFrame(wx.Frame):
'''
This class implements the GUI for the flasher application
'''
subnet = 205
number = 1
restart = 0
def __init__(self, parent, id, title):
'''
Sets up the gui, callback, and widget handles
'''
wx.Frame.__init__(self, parent, id, title)
wx.EVT_CLOSE(self, self.close_clicked)
#---------------------------------------------------------------------------#
# Add button row
#---------------------------------------------------------------------------#
panel = wx.Panel(self, -1)
box = wx.BoxSizer(wx.HORIZONTAL)
box.Add(wx.Button(panel, 1, 'Apply'), 1)
box.Add(wx.Button(panel, 2, 'Help'), 1)
box.Add(wx.Button(panel, 3, 'Close'), 1)
panel.SetSizer(box)
#---------------------------------------------------------------------------#
# Add input boxes
#---------------------------------------------------------------------------#
#self.tdevice = self.tree.get_widget("fileTxt")
#self.tsubnet = self.tree.get_widget("addressTxt")
#self.tnumber = self.tree.get_widget("deviceTxt")
#---------------------------------------------------------------------------#
# Tie callbacks
#---------------------------------------------------------------------------#
self.Bind(wx.EVT_BUTTON, self.start_clicked, id=1)
self.Bind(wx.EVT_BUTTON, self.help_clicked, id=2)
self.Bind(wx.EVT_BUTTON, self.close_clicked, id=3)
#if not root_test():
# self.error_dialog("This program must be run with root permissions!", True)
#---------------------------------------------------------------------------#
# Gui helpers
#---------------------------------------------------------------------------#
# Not callbacks, but used by them
#---------------------------------------------------------------------------#
def show_buttons(self, state=False, all=0):
''' Greys out the buttons '''
if all:
self.window.set_sensitive(state)
self.bstart.set_sensitive(state)
self.tdevice.set_sensitive(state)
self.tsubnet.set_sensitive(state)
self.tnumber.set_sensitive(state)
def destroy_interfaces(self):
''' This is used to reset the virtual interfaces '''
if self.restart:
n = NetworkReset()
n.start()
def error_dialog(self, message, quit=False):
''' Quick pop-up for error messages '''
log.debug("error event called")
dialog = wx.MessageDialog(self, message, 'Error',
wx.OK | wx.ICON_ERROR)
dialog.ShowModel()
if quit: self.Destroy()
dialog.Destroy()
#---------------------------------------------------------------------------#
# Button Actions
#---------------------------------------------------------------------------#
# These are all callbacks for the various buttons
#---------------------------------------------------------------------------#
def start_clicked(self, widget):
''' Starts the simulator '''
start = 1
base = "172.16"
# check starting network
net = self.tsubnet.get_text()
octets = net.split('.')
if len(octets) == 4:
base = "%s.%s" % (octets[0], octets[1])
net = int(octets[2]) % 255
start = int(octets[3]) % 255
else:
self.error_dialog("Invalid starting address!");
return False
# check interface size
size = int(self.tnumber.get_text())
if (size >= 1):
for i in range(start, (size + start)):
j = i % 255
cmd = "/sbin/ifconfig eth0:%d %s.%d.%d" % (i, base, net, j)
os.system(cmd)
if j == 254: net = net + 1
self.restart = 1
else:
self.error_dialog("Invalid number of devices!");
return False
# check input file
if os.path.exists(self.file):
self.show_buttons(state=False)
try:
handle = Simulator(config=self.file)
handle.run()
except ConfigurationException, ex:
self.error_dialog("Error %s" % ex)
self.show_buttons(state=True)
else:
self.error_dialog("Device to emulate does not exist!");
return False
def help_clicked(self, widget):
''' Quick pop-up for about page '''
data = gtk.AboutDialog()
data.set_version("0.1")
data.set_name(('Modbus Simulator'))
data.set_authors(["Galen Collins"])
data.set_comments(('First Select a device to simulate,\n'
+ 'then select the starting subnet of the new devices\n'
+ 'then select the number of device to simulate and click start'))
data.set_website("http://code.google.com/p/pymodbus/")
data.connect("response", lambda w,r: w.hide())
data.run()
def close_clicked(self, event):
''' Callback for close button '''
log.debug("close event called")
reactor.stop()
def file_changed(self, event):
''' Callback for the filename change '''
self.file = widget.get_filename()
class SimulatorApp(wx.App):
''' The main wx application handle for our simulator
'''
def OnInit(self):
''' Called by wxWindows to initialize our application
:returns: Always True
'''
log.debug("application initialize event called")
reactor.registerWxApp(self)
frame = SimulatorFrame(None, -1, "Pymodbus Simulator")
frame.CenterOnScreen()
frame.Show(True)
self.SetTopWindow(frame)
return True
#---------------------------------------------------------------------------#
# Main handle function
#---------------------------------------------------------------------------#
# This is called when the application is run from a console
# We simply start the gui and start the twisted event loop
#---------------------------------------------------------------------------#
def main():
'''
Main control function
This either launches the gui or runs the command line application
'''
debug = True
if debug:
try:
log.setLevel(logging.DEBUG)
logging.basicConfig()
except Exception, e:
print "Logging is not supported on this system"
simulator = SimulatorApp(0)
reactor.run()
#---------------------------------------------------------------------------#
# Library/Console Test
#---------------------------------------------------------------------------#
# If this is called from console, we start main
#---------------------------------------------------------------------------#
if __name__ == "__main__":
main()