Get only valid url from a file in Python

Question

could someone help me please? I have an output.txt file (example file) which looks like this:

output.txt:

account.netflix.com
prod.netflix.com
netflix.com
https://google.com

and I’m trying to put in a file alive.txt just only the existing url with this code

import socket

with open("output.txt", 'r') as f:
    for url in f:
        try:
            addr1 = socket.gethostbyname(url)
            print(addr1 + " is a valid url")

            f = open("alive.txt", "a")
            f.write("\n" + addr1)
            f.close()

        except:
            print("not valid")

f.close()

what am I doing wrong?

are you tried to check if it's valid url and if yes write to file ? — Beny Gj
– Beny Gj, Commented Apr 30, 2020 at 7:30

Zain Arshad · Accepted Answer · 2020-04-30 08:13:45Z

2

The problem is when you read the url from the file. When you read the url in url variable, it has an endling \n newline character with it. You have to remove this and then use the url.

Replace this line:

addr1 = socket.gethostbyname(url)

with this one:

addr1 = socket.gethostbyname(url.rstrip())

Moreover, I think you are not aware of python that much, as your code has various things that needs correction.

You have two file references with same name f. Don't do this, it will lead to some strange behavior.
You are opening the file again and again in for-loop, it's not pythonic. Just open the file once, and when the task ends, close the file.
Using with to open the file you don't have to close the file later on. with is just for this purpose so, that there is no need to close the file.

You can check given code for above mentioned points.

import socket

with open("test.txt", 'r') as in_file, open("alive.txt", "a") as out_file :
    for url in in_file:
        try:
            addr1 = socket.gethostbyname(url.rstrip())
            print(addr1 + " is a valid url")
            out_file.write("\n" + addr1)
        except:
            print("not valid")

edited Apr 30, 2020 at 8:13

answered Apr 30, 2020 at 7:48

Zain Arshad

1,8941 gold badge13 silver badges27 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

caesim Over a year ago

Thank you very much for the explanation, it helps me a lot. And yes, I have started with Python one week ago... :)

Zain Arshad Over a year ago

Glad to help, If it helps never forget to give a upvote :)

AntonioRB · Accepted Answer · 2020-04-30 07:41:08Z

0

Maybe you can try changing the order of your functions :

import socket

f = open("alive.txt", "w")
with open("output.txt") as fp:
    line = fp.readline()

    while line:
        try:
            clean_line = line.strip()
            addr1 = socket.gethostbyname(clean_line)
            print("valid url : " + addr1 + " from " + clean_line)
            f.write(addr1 + "\n")

        except:
            print("not valid: " +addr1 + " from " + clean_line)

        line = fp.readline()

f.close()

edited Apr 30, 2020 at 7:41

answered Apr 30, 2020 at 7:28

AntonioRB

1591 silver badge10 bronze badges

2 Comments

caesim Over a year ago

Nice, thank you for you help! this was exactly what I needed. :) I just replace the write part instead of addr1 I added clean_line

AntonioRB Over a year ago

Glad to help :)

Collectives™ on Stack Overflow

Get only valid url from a file in Python

output.txt:

2 Answers 2

2 Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

output.txt:

2 Answers 2

2 Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related