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Get HTTP response codes with Python

・2 min read

You can get HTTP response codes with Python. This is great to find broken urls or redirects.

The web is dynamic. It's ever changing. Today the popular browsers are Chrome and Firefox. It used to be Netscape and Internet Explorer.

Because it's ever changing, you want to test a website for broken links (404), redirects and other errors. You can do this in Python.

To speed up testing, you want to be using threading. A thread allows you "parallel" execution. Parallel is between quotes because it's not really parallel, but multi-threaded.

So what does that look like in code?

import time
import urllib.request
from threading import Thread

class GetUrlThread(Thread):
    def __init__(self, url):
        self.url = url
        super(GetUrlThread, self).__init__()    

    def run(self):
        resp = urllib.request.urlopen(self.url)
        print(self.url, resp.getcode())

def get_responses():
    urls = ['', '', '']
    start = time.time()
    threads = []
    for url in urls:
        t = GetUrlThread(url)
    for t in threads:
    print("Elapsed time: %s" % (time.time()-start))


Run to test every url in urls: 200 200 200
Elapsed time: 0.496950626373291

A response of 200 means everything is okey. If a page is not found it returns 404. Basically every code other than 200 means there's a problem.

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Discussion (2)

rhymes profile image

Since you only need to check response codes you might want to only issue a HEAD request, this way you avoid downloading the page and discard the content.

If you want to use the standard library you can do something like:

request = urllib.request.Request(url, method="HEAD")
response = urllib.request.urlopen(request)

Unfortunately this will follow redirects, so you end up issuing multiple requests.

I'm sure there's a way to ignore redirects but you'd have to check the documentation.

petercour profile image
petercour Author