python ignore certificate validation urllib2

I want to ignore the certification validation during my request to the server with an internal corporate link.

With python requests library I would do this:

r = requests.get(link, allow_redirects=False,verify=False)

How do I do the same with urllib2 library?

Answers:

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Method 1

In the meantime urllib2 seems to verify server certificates by default.
The warning, that was shown in the past disappeared for 2.7.9 and I currently ran into this problem in a test environment with a self signed certificate (and Python 2.7.9).

My evil workaround (don’t do this in production!):

import urllib2
import ssl

ctx = ssl.create_default_context()
ctx.check_hostname = False
ctx.verify_mode = ssl.CERT_NONE

urllib2.urlopen("https://your-test-server.local", context=ctx)

According to docs calling SSLContext constructor directly should work, too. I haven’t tried that.

Method 2

The easiest way:

python 2

import urllib2, ssl

request = urllib2.Request('https://somedomain.co/')
response = urllib2.urlopen(request, context=ssl._create_unverified_context())

python 3

from urllib.request import urlopen
import ssl

response = urlopen('https://somedomain.co', context=ssl._create_unverified_context())

Method 3

For those who uses an opener, you can achieve the same thing based on Enno Gröper’s great answer:

import urllib2, ssl

ctx = ssl.create_default_context()
ctx.check_hostname = False
ctx.verify_mode = ssl.CERT_NONE

opener = urllib2.build_opener(urllib2.HTTPSHandler(context=ctx), your_first_handler, your_second_handler[...])
opener.addheaders = [('Referer', 'http://example.org/blah.html')]

content = opener.open("https://localhost/").read()

And then use it as before.

According to build_opener and HTTPSHandler, a HTTPSHandler is added if ssl module exists, here we just specify our own instead of the default one.

Method 4

According to @Enno Gröper ‘s post, I’ve tried the SSLContext constructor and it works well on my machine. code as below:

import ssl
ctx = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
urllib2.urlopen("https://your-test-server.local", context=ctx)

if you need opener, just added this context like:

opener = urllib2.build_opener(urllib2.HTTPSHandler(context=ctx))

NOTE: all above test environment is python 2.7.12. I use PROTOCOL_SSLv23 here since the doc says so, other protocol might also works but depends on your machine and remote server, please check the doc for detail.

Method 5

A more explicit example, built on Damien’s code (calls a test resource at http://httpbin.org/). For python3. Note that if the server redirects to another URL, uri in add_password has to contain the new root URL (it’s possible to pass a list of URLs, also).

import ssl    
import urllib.parse
import urllib.request

def get_resource(uri, user, passwd=False):
    """
    Get the content of the SSL page.
    """
    uri = 'https://httpbin.org/basic-auth/user/passwd'
    user = 'user'
    passwd = 'passwd'

    context = ssl.create_default_context()
    context.check_hostname = False
    context.verify_mode = ssl.CERT_NONE

    password_mgr = urllib.request.HTTPPasswordMgrWithDefaultRealm()
    password_mgr.add_password(None, uri, user, passwd)

    auth_handler = urllib.request.HTTPBasicAuthHandler(password_mgr)

    opener = urllib.request.build_opener(auth_handler, urllib.request.HTTPSHandler(context=context))

    urllib.request.install_opener(opener)

    return urllib.request.urlopen(uri).read()

Method 6

urllib2 does not verify server certificate by default. Check this documentation.

Edit: As pointed out in below comment, this is not true anymore for newer versions (seems like >= 2.7.9) of Python. Refer the below ANSWER

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0