wk8_ex1.py

# IP address validator with Try-Exception as Function

def IPvalidator(ip_address):
    ipList = ip_address.split('.')
    validIP = True
# Does input have four sections?
    if len(ipList) != 4:
        #print("Invalid input. Incorrect number of octets. Err 1")
        validIP = False

# Are the four sections integers?
#    print list(enumerate(ipList))
#    octets = []
    for i, octet in enumerate(ipList):
        try:
            ipList[i] = int(octet)
            #print(ipList[i])
        except TypeError:
            #print("Invalid input. %d is not an integer. Err 2" % ipList[i])
            validIP = False
        except ValueError:
            #print("Invalid input. %s is not an integer. Err 2" % octet)
            validIP = False

# First octet must be 223 or less
    try:
        if int(ipList[0]) <= 0 or int(ipList[0]) > 223:
            #print("Invalid input. %d is not a valid octet. Err 3" % ipList[0])
            validIP = False
    except ValueError:
        #print("Invalid input. %s is not a valid octet. Err 3" % ipList[0])
        validIP = False

# First octet cannot be 127
    try:
        if int(ipList[0]) == 127:
            #print("Invalid input. IP address can not be in 127.0.0.0 subnet. Err 4")
            validIP = False
    except ValueError:
        #print("Invalid input. %s is not an integer. Err 4" % ipList[0])
        validIP = False

# IP cannot be on the 169.254.0.0 network
    try:
        if int(ipList[0]) == 169 and int(ipList[1]) == 254:
            #print("Invalid input. IP address can not be in 169.254.0.0 subnet. Err 5")
            validIP = False
    except ValueError:
        #print("Invalid input. %s is not an integer. Err 5" % ipList[1])
        validIP = False

# Are the octets integers between 0 and 255?
    for i in ipList:
        try:
            #if int(i) >= 1:
            if int(i) < 0 or int(i) > 255:
                #print("Invalid input. %d is not a valid octet. Err 6" % int(i))
                validIP = False
        except ValueError:
            validIP = False

    return validIP

# Separate executable code from importable code
if __name__ == '__main__':
    print
        # Create a bunch of test cases
    test_ip_addresses = {
        '192.168.1'     :   False,
        '10.1.1.'       :   False,
        '10.1.1.x'      :   False,
        '0.77.22.19'    :   False,
        '-1.88.99.17'   :   False,
        '241.17.17.9'   :   False,
        '127.0.0.1'     :   False,
        '169.254.1.9'   :   False,
        '192.256.7.7'   :   False,
        '192.168.-1.7'  :   False,
        '10.1.1.256'    :   False,
        '1.1.1.1'       :   True,
        '223.255.255.255':  True,
        '223.0.0.0'     :   True,
        '10.200.255.1'  :   True,
        '192.168.17.1'  :   True,
    }

    for ip_addr,expected_result in test_ip_addresses.items():
        if IPvalidator(ip_addr):
            print("%s is valid." % ip_addr)
        else:
            print("%s is NOT valid." % ip_addr)