The gocept.webtoken distribution

This library helps you using JWT tokens with the Zope Component Architecture (ZCA).

This package is compatible with Python version 2.7, 3.6 up to 3.8.

Copyright (c) 2015-2020 gocept gmbh & co kg

All Rights Reserved.

This software is subject to the provisions of the Zope Public License, Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution. THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE.

Installation

This package requires cryptography, which needs some install attention. Please refer to its install documentation for further information.

Contents

• Installation
• Usage
  • The CryptographicKey utility
  • Creating a token
  • Creating a Bearer Authorization header
  • Extracting a token from a Bearer Authorization header
  • Decoding a token

Usage

The CryptographicKey utility

gocept.webtoken uses a global utility of the class gocept.webtoken.CryptographicKeys, which provides cryptographic keys for different purposes. It loads a set of public and private keys from disk. It takes the filesystem path to your key files and a list of key names:

>>> import gocept.webtoken
>>> import pkg_resources
>>> path_to_keys = pkg_resources.resource_filename(
...     'gocept.webtoken', 'testing/keys')
>>> keys = gocept.webtoken.CryptographicKeys(
...     path_to_keys, ['key1'])

For each of the names, a private key file of the same name and a public key file (with a .pub suffix) must reside inside the keys_dir.

The utility needs to be registered at the ZCA, either via a zcml file or via:

>>> import zope.component
>>> zope.component.provideUtility(keys)

Creating a token

Create a signed web token with the function create_web_token. You will need the private key name, which was registered at the CryptographycKey utility. It is referenced by its name and the suffix -private:

>>> expires_in = 300  # The token is valid for 300 seconds
>>> payload = {'your': 'data'}
>>> result = gocept.webtoken.create_web_token(
...     'key1-private', 'issuer', 'subject', expires_in, payload)
>>> sorted(result.keys())
['data', 'token']

The token is available under the key token, while the data encoded in the token is placed under the key data.

Creating a Bearer Authorization header

You can create an Bearer Authorization header either from a token_dict as returned by create_web_token or from a token directly:

>>> gocept.webtoken.create_authorization_header(b'<TOKEN>')
('Authorization', 'Bearer <TOKEN>')

Extracting a token from a Bearer Authorization header

Extract the token from a dict containing the headers of you request or from the value of the HTTP Authorization header itself:

>>> request_headers = dict(Authorization='Bearer <TOKEN>')
>>> b'<TOKEN>' == gocept.webtoken.extract_token(request_headers)
True

Decoding a token

Decode a signed web token with the function decode_web_token. You will need the public key name, which was registered at the CryptographycKey utility. It is referenced by its name and the suffix -public:

>>> result = gocept.webtoken.decode_web_token(
...     result['token'], 'key1-public', 'subject')

Note that the subject must match the subject given when the token was created.

The result contains all data encoded in the token. You can find the payload under the key data:

>>> {'your': 'data'} == result['data']
True