Value for the second or third octet that is equivalent to the octet value entered by the user

Python Help
1

I’m trying to figure out how to take a octet input value and print IP addresses in a file that have a value for the second or third octet that matches the input value. I set up a code already that prompts the user to enter a value and compares the value to the entirety of the file, printing out each line the input value is included in. The problem is that I need to print the ones where the input value is only a second or third octet. Here is my code at the moment.

# opening and reading the file 
file_read = open('Applog.txt', "r")

#Prompt the user for an IP address octet value
text = input("Enter the IP address octet value: ")

# read the file line by line.
lines = file_read.readlines()

new_list = []
idx = 0

# loop through each line in the file
for line in lines:
    # If the line has a input string, take the index of that line and place it into a new list
    if text in line:
        new_list.insert(idx, line)
        idx += 1
file_read.close()

# If the length of new list is 0, the input string isn't found in the text file
if len(new_list)==0:
    print("\n\"" +text+ "\" is not found in \"" +'Applog.txt'+ "\"!")
else:
    # displays the lines containing given octet value
    lineLength = len(new_list)
    print("\n**** Lines containing \"" +text+ "\" ****\n")
    for i in range(lineLength):
        print(end=new_list[i])
    print()

The text file is filled with lines like

[node1] - 190.223.252.106 - User Successful Login
[node2] - 239.84.157.20 - User Successful Profile Picture Upload
[node2] - 87.130.185.37 - User Successful Login
[node6] - 210.155.211.219 - User Successful Payment
[node5] - 64.103.198.103 - User Successful Login
[node2] - 136.4.60.67 - User Successful Login
[node7] - 191.161.59.79 - User Failed Login
[node1] - 128.215.207.129 - User Failed Payment
[node6] - 203.141.97.180 - User Successful Profile Picture Upload
[node6] - 172.218.65.224 - User Successful Profile Picture Upload

I hope someone can find out what I’m missing!

2

In order to do that you need to parse the lines to extract the IP
addresses, and then parse those to extract the octets. As it is, your
test reads:

 if text in line:

which just looks for a substring anywhere in the line. Suppose the
user entered 6. That would match, 190.223.252.106 but also,
excitingly, [node6].

It looks like your fields are separated by the string " - ". You could
go:

 fields = line.split(' - ')

and look at fields[1]. You can use an unpacking assignmenthere:

 node_part, ip_part, comment = line.split(' - ', 2)

Then you want to break the ip_part apart on dots:

 ip_parts = ip_part.split('.')

and then test ip_parts[1] and ip_parts[2] against the value in
text.

Cheers,
Cameron Simpson cs@cskk.id.au

3

I tried your solution but it didn’t seem to change anything. The code didn’t break or anything, it just stayed the same as the previous take. Did I do this right?

for line in lines:
    # If the line has a input string, take the index of that line and place it into a new list
    if text in line:
        new_list.insert(idx, line)
        idx += 1
        fields = line.split('-')
        node_part, ip_part, comment = line.split(' - ', 2)
        ip_parts = ip_part.split('.')
file_read.close()
4

Not really. Let’s look at the if-statement:

 if text in line:
     new_list.insert(idx, line)
     idx += 1
     fields = line.split('-')
     node_part, ip_part, comment = line.split(' - ', 2)
     ip_parts = ip_part.split('.')

Your test for the octet is unchanged. It still tests text in line.
You seem to have missing the part in my message which said:

and then test ip_parts[1] and ip_parts[2] against the value in
text.

All your stuff with fields and ip_parts etc happens after you’ve
decided if the line matches. You want to make that decision after
you’ve got ip_parts, and base that decision on the apprpriate test of
those parts instead of using the overly broad text in line test.

So all the parsing to get ip_parts needs to be before the
if-statement, and the if-statement needs to test the desired bits of
ip_parts, not the whole line.

Cheers,
Cameron Simpson cs@cskk.id.au

5

Thank you for your help, but this is giving one more issue. I figured out where to put the code but now the input is giving me second/third octets with the numbers 0 and 1 instead of just 100. Here is the full code to recap.

# opening and reading the file 
file_read = open('Applog.txt', "r")

#Prompt the user for an IP address octet value
text = input("Enter the IP address octet value: ")

# read the file line by line.
lines = file_read.readlines()

new_list = []
idx = 0

# loop through each line in the file
for line in lines:
    fields = line.split('-')
    node_part, ip_part, comment = line.split(' - ', 2)
    ip_parts = ip_part.split('.')
    # If the line has a input string, take the index of that line and place it into a new list
    if ip_parts[1] in text:
        new_list.insert(idx, line)
        idx += 1
    if ip_parts[2] in text:
        new_list.insert(idx, line)
        idx += 1
file_read.close()

# If the length of new list is 0, the input string isn't found in the text file
if len(new_list)==0:
    print("\n\"" +text+ "\" is not found in \"" +'Applog.txt'+ "\"!")
else:
    # displays the lines containing given octet value
    lineLength = len(new_list)
    print("\n**** Lines containing \"" +text+ "\" ****\n")
    for i in range(lineLength):
        print(end=new_list[i])
    print()
6

Now that you have parsed the IP address you use == not in.

Becomes

    If ip_parts[1] == text:
7

fields = line.split(‘-’)

You’re not using this line, it can be discarded.

node_part, ip_part, comment = line.split(’ - ‘, 2)
ip_parts = ip_part.split(’.')

If the line has a input string, take the index of that line and place it into a new list

if ip_parts[1] in text:

Barry has pointed out that because the text should be an exact match for
the particular ip_part you’re testing, you want == and not in. The
in operator with strings is a substring test.

   new_list.insert(idx, line)
   idx += 1

if ip_parts[2] in text:
new_list.insert(idx, line)
idx += 1

The other problem is that if the text matches both the second and
third octets you’re adding the line twice, once for each match. You want
an or test:

 if ip_parts[1] == text or ip_parts[2] == text:

This tests both octets, and is true if one or the other or both match.
Then you’d have just one if-statement and add the line just once.

Cheers,
Cameron Simpson cs@cskk.id.au

8

Thank you everyone, you have fixed my problem