Python - Print line based on partial string-CodePudding

I have 2 files that I am wanting to check against each other and pull out the line that they are contained in.

I was trying to do it with regex but I keep getting this error, presuming it's because I'm reaching into a file rather than just presenting a string directly

File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.9_3.9.2544.0_x64__qbz5n2kfra8p0\lib\re.py", line 248, in finditer
    return _compile(pattern, flags).finditer(string)
TypeError: expected string or bytes-like object

This is what I'm using for the regex search

regex = r"\d(.*(10.0.0.0).*)"

with open('test1.txt', 'r') as file1:
    test = file1.read().splitlines()
    matches = re.finditer(regex, test)

    for matchNum, match in enumerate(matches, start=1):
        print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group()))

I have also tried this, but still comes up with an error

with open("test1.txt") as file1, open("test2") as file2:
    st = set(map(str.rstrip,file1))
    for line in file2:
        spl = line.split(None, 1)[0]
        if spl in st:
            print(line.rstrip())

The error is

IndexError: list index out of range

I am trying to match a list of IPs to the output from a router, so the test2 file will look like this

10.0.0.0/8
11.0.0.0/8
12.0.0.0/8
13.0.0.0/8

With the router output looking like

1 X test         10.0.0.0/8                          nov/19/2021 13:03:08
2 X test         11.0.0.0/8                          nov/19/2021 13:03:08
3 X test         12.0.0.0/8                          nov/19/2021 13:03:08
4 X test         13.0.0.0/8                          nov/19/2021 13:03:08

I am wanting the entire line from the router to be matched just with the IP rather than having to put the entire expected output

Hope this is enough to go off, still pretty new to all this, cheers

CodePudding user response：

If you have a file with the actual IPs, and you don't need regexes, then you can do something like this

my_str = """
1 X test         10.0.0.0/8                          nov/19/2021 13:03:08
2 X test         11.0.0.0/9                          nov/19/2021 13:03:08
3 X test         12.0.0.0/12                          nov/19/2021 13:03:08
4 X test         13.0.0.0/2                          nov/19/2021 13:03:08
5 X test         555.0.0.0/2                          nov/19/2021 13:03:08 #expecting this to not be printed
"""

keep_ips = [' 10.0.0.0/8 ', ' 11.0.0.0/9 ', ' 12.0.0.0/12 ', ' 13.0.0.0/2 ']


for line in my_str.split('\n'):
    if any(ip in line for ip in keep_ips):
        print(line)

I added the padding of spaces in the keep_ips because otherwise you could match on something like 113.0.0.0/25, because it contains the substring 13.0.0.0/2

You could refactor this code to read in the lines from the router, then the lines for the IPs, add spaces to either end of the IPs, then use this logic, using any

I hope this works for you now

CodePudding user response：

Full answer is

with open("router_output.txt") as file1, open("list_of_ips.txt") as file2:
    ips_to_keep = file2.read().splitlines()
    router_lines = file1.read().splitlines()

ips_to_keep = [" "   ip   " " for ip in ips_to_keep]

for line in router_lines:
    if any(ip in line for ip in ips_to_keep):
        print(line)

assuming that your file has spaces and not tabs :)