POST with Python not working

Question

I've read many posts on the Internet, but none of them seems to work for me. I have a web form which requires an username and a password in order to log in. Here's a snippet of code among those I tried so far

params = urllib.parse.urlencode({'login' : 'user', 'password' : 'pwd'})
f = urllib.request.urlopen("https://example.com/login.php?%s" % params)
print(f.read().decode('utf-8'))

However it gives me back the login page source instead of the "user panel" that appears after log in. If I write https:/example.com/login.php?login=user&password=pwd in the url bar of the browser, it logs me in. The goal is to get the page source that appears after logging in (the "user panel"). Can anyone help me please?

Using Python 3.5

• Juanín: Maybe the login just redirects you to the user panel after the login or maybe you are missing some headers on the request
• shiva: You are making a GET request instead of a POST.
• Padraic Cunningham: Do yourself a favour and use requests, docs.python-requests.org/en/master/user/quickstart
• Luca Mozzo: @PadraicCunningham I've been trying to make it work for 20 mins on Windows, let me try on Unix
• Padraic Cunningham: @LucaMozzo, can you share the url?

Answer 1

The correct usage is

f = urllib.request.urlopen("https://example.com/login.php", data=params)

From urllib.request documentation:

data may be a string specifying additional data to send to the server, or None if no such data is needed.

Note that this will send a POST request instead of a GET. If you have to send a GET request, you can simply do the following:

f = urllib.request.urlopen("https://example.com/login.php?user={0}&password={1}".format('user', 'pwd'))

• Luca Mozzo: Unfortunately I still get back the login page also by doung in this way (it asks me an array of bytes so I had to write data=params.encode("utf-8") instead)
• Selcuk: @LucaMozzo The site might require a GET request. Did you try the second method?
• Luca Mozzo: The HTML says "method=post", but I've just tried it and still nothing!
• TryToSolveItSimple: @LucaMozzo if you use the last line from Selcuk's answer it should be the same as if you put it in the browser url bar. Have you run that line of code?

Answer 2

According to the documentation for urllib, you need to pass keyword argument data (or the second positional argument) to urlopen, instead of adding them to the url:

import urllib
params = urllib.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0})
f = urllib.urlopen("http://www.musi-cal.com/cgi-bin/query", params)
print f.read()