How can I percent-encode URL parameters in Python?

If I do

url = "http://example.com?p=" + urllib.quote(query)

1. It doesn't encode / to %2F (breaks OAuth normalization)
2. It doesn't handle Unicode (it throws an exception)

Is there a better library?

Python 2

From the documentation:

urllib.quote(string[, safe])

> Replace special characters in string > using the %xx escape. Letters, digits, > and the characters '_.-' are never > quoted. By default, this function is > intended for quoting the path section > of the URL.The optional safe parameter > specifies additional characters that > should not be quoted — its default > value is '/'

That means passing '' for safe will solve your first issue:

>>> urllib.quote('/test')
'/test'
>>> urllib.quote('/test', safe='')
'%2Ftest'

About the second issue, there is a bug report about it. Apparently it was fixed in Python 3. You can workaround it by encoding as UTF-8 like this:

>>> query = urllib.quote(u"Müller".encode('utf8'))
>>> print urllib.unquote(query).decode('utf8')
Müller

By the way, have a look at urlencode.

Python 3

In Python 3, the function quote has been moved to urllib.parse:

>>> import urllib.parse
>>> print(urllib.parse.quote("Müller".encode('utf8')))
M%C3%BCller
>>> print(urllib.parse.unquote("M%C3%BCller"))
Müller

In Python 3, urllib.quote has been moved to urllib.parse.quote, and it does handle Unicode by default.

>>> from urllib.parse import quote
>>> quote('/test')
'/test'
>>> quote('/test', safe='')
'%2Ftest'
>>> quote('/El Niño/')
'/El%20Ni%C3%B1o/'

I think module requests is much better. It's based on urllib3.

You can try this:

>>> from requests.utils import quote
>>> quote('/test')
'/test'
>>> quote('/test', safe='')
'%2Ftest'

_{My answer is similar to Paolo's answer.}

If you're using Django, you can use urlquote:

>>> from django.utils.http import urlquote
>>> urlquote(u"Müller")
u'M%C3%BCller'

Note that changes to Python mean that this is now a legacy wrapper. From the Django 2.1 source code for django.utils.http:

A legacy compatibility wrapper to Python's urllib.parse.quote() function.
(was used for unicode handling on Python 2)

It is better to use urlencode here. There isn't much difference for a single parameter, but, IMHO, it makes the code clearer. (It looks confusing to see a function quote_plus! - especially those coming from other languages.)

In [21]: query='lskdfj/sdfkjdf/ksdfj skfj'

In [22]: val=34

In [23]: from urllib.parse import urlencode

In [24]: encoded = urlencode(dict(p=query,val=val))

In [25]: print(f"http://example.com?{encoded}")
http://example.com?p=lskdfj%2Fsdfkjdf%2Fksdfj+skfj&val=34

Documentation

• urlencode

• quote_plus