wc_monitor.py

# -*- coding: utf-8 -*-

import suds
import sys
import xml
import argparse
import getpass
import time
import datetime
from Environment import readSettings


def main(args):

    ####################################################################################################################
    ### Check all arguments
    ####################################################################################################################

    errorMessage =  "No path to SETTINGS file specified. Provide one via '-f my_settingsFile' or {..., 'settingsFile':'my_settingsFile', ...}"
    try:
        if args['settingsFile'] is None or not args['settingsFile']:
            print(errorMessage)
            sys.exit(1)
        else:
            settingsFile = args['settingsFile']
    except KeyError:
        print(errorMessage)
        sys.exit(1)
    settings = readSettings(settingsFile)

    errorMessage = "No username specified. Provide one via '-u my_username' or {..., 'username':'my_username', ...} or WC_USERNAME=my_username"
    try:
        if args['username'] is None or not args['username']:
            if not settings['WC_USERNAME']:
                print(errorMessage)
                sys.exit(1)
            else:
                username = settings['WC_USERNAME']
        else:
            username = str(args['username'])
    except KeyError:
        print(errorMessage)
        sys.exit(1)

    # The password cannot be given via environment variable
    errorMessage = "No password specified. Provide one via {..., 'password':'my_password', ...}"
    try:
        if args['password'] is None or not args['password']:
            print(errorMessage)
            sys.exit(1)
        else:
            password = args['password']
    except KeyError:
        print(errorMessage)
        sys.exit(1)

    nodeDefault = '/trees/geographic'
    errorMessage = "No node specified. Provide one via '-n my_node' or {..., 'node':'my_node', ...} or WC_NODE=my_node. " \
        "Using a default now: '" + nodeDefault + "'"
    try:
        if args['node'] is None or not args['node']:
            if not settings['WC_NODE']:
                print(errorMessage)
                node = nodeDefault
            else:
                node = settings['WC_NODE']
        else:
            node = str(args['node'])
    except KeyError:
        print(errorMessage)
        node = nodeDefault

    urlDefault = 'https://webctrl.rz-berlin.mpg.de'
    errorMessage = "No URL specified. Provide one via '-url my_url' or {..., 'url':'my_url', ...} or WC_URL=my_url. " \
        "Using a default now: '" + urlDefault + "'"
    try:
        if args['url'] is None or not args['url']:
            if not settings['WC_URL']:
                print(errorMessage)
                url = urlDefault
            else:
                url = settings['WC_URL']
        else:
            url = str(args['url'])
    except KeyError:
        print(errorMessage)
        url = urlDefault
    wsdlFile = url + '/_common/webservices/Eval?wsdl'

    ####################################################################################################################
    ### Connect to the webCTRL server
    ####################################################################################################################

    try:
        client = suds.client.Client(wsdlFile, username=username, password=password)
    except AttributeError:
        print 'Error: Incorrect username and/or password'
    except xml.sax._exceptions.SAXParseException:
        print 'Error: Incorrect/Misspelled WSDL file. It should be: http(s)://URL?wsdl'
        sys.exit(1)
    except:
        print("Unexpected error:", sys.exc_info()[0])
        print('Perhaps your URL to the WSDL file is not correct.')
        sys.exit(1)

    ####################################################################################################################
    ### Go into an infinite loop and retrieve a value every second but only print it to the screen if the current value
    ### is different from the last one; the loop is exited once CTRL+C is pressed
    ####################################################################################################################

    currentValue = 0
    try:
        while True:
            oldValue = currentValue
            try:
                currentValue = client.service.getValue(node)
            except suds.WebFault as fault:
                print fault
                sys.exit(1)

            if currentValue is None:
                print "You haven't specified a particular controller. The command could look like this:"
                print '$ wc_monitor "#controller/m001"'
                sys.exit(1)
            elif currentValue != oldValue:
                print datetime.datetime.now().time().strftime("%H:%M:%S") + "    " + currentValue
                time.sleep(1)
            else:
                time.sleep(1)
    except KeyboardInterrupt:
        print('Exiting due to keyboard interupt...')


# The argument parser is only called if this script is called as a script/executable (via command line) but not when
# imported by another script
if __name__ == '__main__':
    if len(sys.argv) < 2:
        print "You haven't specified any arguments. Use -h to get more details on how to use this command."
        sys.exit(1)

    parser = argparse.ArgumentParser()
    parser._action_groups.pop()
    required = parser.add_argument_group('required arguments')
    optional = parser.add_argument_group('optional arguments (can also be specified via SETTINGS file)')
    required.add_argument('--password', '-p', type=str, default=None, help='Password for the login to the WebCTRL server')
    required.add_argument('--settingsFile', '-f', type=str, default=None, help='File name of settings containing WC_* variables')
    required.add_argument('--username', '-u', type=str, default=None, help='Username for the login to the WebCTRL server')
    optional.add_argument('--url', '-url', type=str, default=None, help="URL of the webctrl server like 'http(s)://webctrl.de'")
    optional.add_argument('--node', '-n', type=str, default=None, help='Path to the point or node that you want to monitor')
    args = parser.parse_args()

    # Get the password if it hasn't been passed as argument
    if args.password is None or not args.password:
        args.password = getpass.getpass('No password specified via -p. Please enter your WebCTRL login password: ')

    # Convert the argparse.Namespace to a dictionary via vars(args)
    main(vars(args))
    sys.exit(0)