rpc3Control.py

#!/usr/bin/python

# Control Class for the Baytech RPC3
# J. Adams <jna@retina.net>

from pexpect import *
import sys
import re
import syslog
import time
import os
import errno
import datetime
import fcntl

class rpc3ControlError(Exception):
    def __init__(self, value):
        self.value = value
    def __str__(self):
        return repr(self.value)

class rpc3Control:
    # Class to control a Baytech RPC-3
    child = None
    status = {}
    name = {}
    statuscached = False
    unitid = ""

    def __init__(self, hostname, user, password=None, debug=False):
        self.hostname = hostname
        self.user = user
        self.password = password
        self.debug = debug
        self.connect()
        self.unitid = ""
        self.child.delaybeforesend = .05

      #  the RPC supports username, or password, or both
      #  so we support both of those cases in this code.

        # get unit id
        check = self.child.expect([".*Unit ID: (.*)", EOF, TIMEOUT], timeout=3)
        if check == 0:
                self.unitid = self.child.match.group(1)
        if check > 0:
                if check == 1:
                        raise rpc3ControlError("EOF during read")
                else:
                        raise rpc3ControlError("Timeout during read in init function")

#       print(str(self.unitid))
        if user != None:
            self.es("Enter username>", user)

        if password != None:
            self.es("Enter password>", password)

    def file_exists(self, path, filename):
        for file_or_folder in os.listdir(path):
                if file_or_folder == filename:
                        return True
        return False

    def es(self,str_expect,str_send):

       # a pexpect helper method; expect and send with error monitoring

        result = self.child.expect([str_expect, EOF, TIMEOUT], timeout=3)
#        print(str(self.child))

        if result == 0:
            self.child.send("%s\r" % str_send)
            return

        if result > 0:
            if result == 1:
                raise rpc3ControlError("EOF during read")
            else:
                raise rpc3ControlError("Timeout during read in ES function")

    def connect(self):
        if self.child == None:
            self.child = spawn("telnet " + self.hostname)
            result = self.child.expect(["Connected to", EOF, TIMEOUT], timeout=3)
            #print (self.child)
            #self.child.send("\r")

        if self.debug == True:
            self.child.logfile = sys.stdout

    def outlet(self,outlet_number,state):

      #  control an outlet
      #  state is one of on, off,or reboot
      #  outlet_number is an integer.

        if state not in ("on", "off", "reboot"):
            self.child.send("6\r")
            self.child.terminate()
            raise rpc3ControlError('Invalid outlet state')

        if int(outlet_number) > 8 or int(outlet_number) < 1:
            self.child.send("6\r")
            self.child.terminate()
            return None

        self.es("Enter Selection>", "1")
        self.es("RPC-3>", "%s %d\rY"  % (state, outlet_number) )
        self.es("RPC-3>", "MENU")

        self.statuscached = False
        self.child.send("6\r")
        self.child.terminate()

        return True

    def outlet_status(self, outlet_number, ignore_cache = True):
        # Get the status of an outlet

        if self.statuscached == True and ignore_cache != True:
            if self.user == "admin" or self.user == None:
                self.child.send("6\r")
            else:
                self.child.send("LOGOUT\r")
            return (self.status[outlet_number],self.name[outlet_number])

        if int(outlet_number) > 8 or int(outlet_number) < 1:
            if self.user == "admin" or self.user == None:
                self.child.send("6\r")
            else:
                self.child.send("LOGOUT\r")
            return None

        if self.user == "admin" or self.user == None:
                self.es("Enter Selection>", "1")
                self.es("RPC-3>", "MENU")

        # parse the output
        inlist = False

        for line in self.child.before.split('\n'):
            if line.rstrip() == "" and inlist:
                inlist = False

        #without the below check i would get parse errors randomly when checking state
            if line.rstrip() == "    5)...Reset Unit" and inlist:
                inlist = False

            if inlist:

                m = re.match('^ .....([0-9]) ..... (...........) ([0-9]) ..... (On|Off)',line)

                self.name[int(m.group(1))] = m.group(2).rstrip()

                if m.group(4) == "On":
                    self.status[int(m.group(1))] = True
                else:
                    self.status[int(m.group(1))] = False

            if line.find("Status") != -1:
                inlist = True

        self.statuscached = True

        if self.user == "admin" or self.user == None:
                self.child.send("6\r")
                self.child.terminate()
        else:
                self.child.send("LOGOUT\r")
                self.child.terminate()

        #Write all outlet status to file and lock the file. Doing this because i use this script with homebridge and siri executes the script to get status for each outloet. The RPC unit allows only 4 telnet sesions for user admin at a time. I have homebridge use the this status file instead of logging in if the status file is recent.
        lock_filename = 'telnetrunning.txt'
        frunning = open(lock_filename,'w+')
        while True:
                try:
                        fcntl.flock(frunning, fcntl.LOCK_EX | fcntl.LOCK_NB)
                        break
                except IOError as e:
                        # raise on unrelated IOErrors
                        if e.errno != errno.EAGAIN:
                                raise
                        else:
                                time.sleep(0.05)

        i=1
        sttime = str(int(round(time.time() * 1000)))
        frunning.write(sttime + "," + str(outlet_number) + ",\r\n")
        while  (i <= 8):
                writeText = "%d," % (i)
                stringOutletStatus = "%s," % self.status[i]
                stringOutletName = "%s" % self.name[i]
                frunning.write(writeText + stringOutletStatus + stringOutletName  + "\r\n")
                i=i+1
        fcntl.flock(frunning, fcntl.LOCK_UN)
        frunning.close()
        return (self.status[outlet_number],self.name[outlet_number])

# fetch credentials
# the credentials should be in a file called ".credentials" and in the form "hostname:user:pass" on one line.
def load_credentials(credentials):
    user = None
    pw = None
    rpc = None
    err = None
    whitelist = None

    try:
        f = open(credentials, 'r')
        (rpc, user, pw, w) = f.readline().rstrip().split(":",3)
        whitelist = w.split(",")
        f.close()
    except IOError:
        err = "FATAL: Couldn't open credentials file"
    except ValueError:
        err = "FATAL: Malformed %s file. Credentails should be in the form \"host:user:pw\"" % credentials

    if err != None:
        syslog.syslog(syslog.LOG_ERR, err)
        print >> sys.stderr, err
        sys.exit(1)

    return (rpc,user,pw,whitelist)