apistar_jwt 0.5.0

A JSON Web Token Component for API Star

apistar-jwt

JSON Web Token Component for use with API Star >= 0.4.

Installation

$ pip install apistar-jwt

Alternatively, install through pipenv.

$ pipenv install apistar-jwt

Usage

Register the JWT Component with your APIStar app.

from apistar import App
from apistar_jwt.token import JWT

routes = [
  # ...
]

components = [
    JWT({
        'JWT_SECRET': 'BZz4bHXYQD?g9YN2UksRn7*r3P(eo]P,Rt8NCWKs6VP34qmTL#8f&ruD^TtG',
    }),
]

app = App(routes=routes, components=components)

Inject the JWT component in your login function and use it to encode the JWT.

from apistar import exceptions, types, validators
from apistar_jwt.token import JWT

class UserData(types.Type):
    email = validators.String()
    password = validators.String()


def login(data: UserData, jwt: JWT) -> dict:
    # do some check with your database here to see if the user is authenticated
    user = db_login(data)
    if not user:
        raise exceptions.Forbidden('Incorrect username or password.')
    payload = {
        'id': user.id,
        'username': user.email,
        'random_data': '102310',
    }
    token = jwt.encode(payload)
    if token is None:
        # encoding failed, handle error
        raise exceptions.BadRequest()
    return {'token': token}

Inject the JWTUser component in any resource where you want authentication with the provided JWT.

from apistar_jwt.token import JWTUser

def welcome(user: JWTUser) -> dict:
    message = f'Welcome {user.username}#{user.id}, here is your random data: {user.token["random_data"]}'
    return {'message': message}

Note

Requests made with JWT The token must be passed as an Authorization header using the Bearer scheme in requests made to a resource.

$ curl -i -H "Accept: application/json" -H "Content-Type: application/json" -H "Authorization: Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJ1c2VyIjoxfQ.fCqeAJGHYwZ9y-hJ3CKUWPiENOM0xtGsMeUWmIq4o8Q" http://localhost:8080/some-resource-requiring-jwt-auth

Decorators

We provide two decorators for convenience to enforce authentication required or allow anonymous users for a route:

from apistar_jwt.token import JWTUser
from apistar_jwt.decorators import anonymous_allowed, authentication_required


@authentication_required
def auth_required(request: http.Request, user: JWTUser):
    return user.__dict__


@anonymous_allowed
def anon_allowed(request: http.Request, user: JWTUser):
    if user:
        return user.__dict__
    return None

The @authentication_required decorator will enforce the user to be logged in for that route. Meanwhile the @anonymous_allowed will set user: JWTUser=None and allow anonymous users to hit the route. The default behavior is @authentication_required so you do not need to annotate with this decorator, it is just to help your code be explicit.

Settings

There are two settings this package uses to identify the username and user_id keys in the JWT payload, they are by default:

{
  'JWT_USER_ID': 'id',
  'JWT_USER_NAME': 'username',
}

If your JWT uses some other kind of key, override these keys when you instantiate your component:

from apistar_jwt.token import JWT

components = [
  JWT({
    'JWT_USER_ID': 'pk',
    'JWT_USER_NAME': 'email',
  })
]

JWT_WHITE_LIST allows you to specify a list of route functions that will not require JWT authentication. This is useful if you have setup a default authentication policy but want to open up certain routes, especially ones that might be in third party packages or in apistar itself like the schema docs.

from apistar_jwt.token import JWT

components = [
  JWT({
    'JWT_WHITE_LIST': ['serve_schema', 'home'],
  })
]

In this instance, the serve_schema and home Routes will not require JWT authentication.

JWT_ALGORITHMS is related to the algorithms used for decoding JWTs. By default we only use 'HS256' but JWT supports passing an array of supported algorithms which it will sequentially try when attempting to decode.

from apistar_jwt.token import JWT

components = [
  JWT({
    'JWT_ALGORITHMS': ['HS256', 'RSA512'],
  })
]

JWT_SECRET is a long, randomized, secret key that should never be checked into version control.

from apistar_jwt.token import JWT

components = [
  JWT({
    'JWT_SECRET': 'QXp4Z83.%2F@JBiaPZ8T9YDwoasn[dn)cZ=fE}KqHMJPNka3QyPNq^KnMqL$oCsU9BC?.f9,oF2.2t4oN?[g%iq89(+'
  })
]

For all other settings, use JWT_OPTIONS key which will pass them along to the underlying PyJWT library when decoding.

from apistar_jwt.token import JWT

components = [
  JWT({
    'JWT_OPTIONS': {
      'issuer': 'urn:foo',
      'audience': 'urn:bar',
      'leeway': 10,
    },
  })
]

Quick rundown of the options:

audience is the urn for this applications audience, it must match a value in the aud key of the payload. Read more about audience claim.

issuer is the urn of the application that issues the token, it must match a value in the iss key of the payload. Read more about the issuer claim

leeway is the number of seconds of margin an expiration time claim in the past will still be valid for.

A fully customized JWT component would like like the following:

from apistar_jwt.token import JWT

components = [
  JWT({
    'JWT_ALGORITHMS': ['HS256', 'RSA512'],
    'JWT_USER_ID': 'pk',
    'JWT_USER_NAME': 'email',
    'JWT_SECRET': 'QXp4Z83.%2F@JBiaPZ8T9YDwoasn[dn)cZ=fE}KqHMJPNka3QyPNq^KnMqL$oCsU9BC?.f9,oF2.2t4oN?[g%iq89(+',
    'JWT_OPTIONS': {
      'issuer': 'urn:foo',
      'audience': 'urn:bar',
      'leeway': 10,
    },
    'JWT_WHITE_LIST': ['serve_schema'],
  })
]

Developing

This project uses pipenv to manage its development environment, and pytest as its tests runner. To install development dependencies:

pipenv install --dev

To run tests:

pipenv shell
pytest

This project uses Codecov to enforce code coverage on all pull requests. To run tests locally and output a code coverage report, run:

pipenv shell
pytest --cov=apistar_test/

HISTORY

0.4.2

• Everything is now a top level export as well, e.g. from apistar_jwt import JWT (thanks @jgiradet)

0.4.1

• Added decorator support, @anonymous_allowed and @authentication_required
• Added back in test suite
• Updated typings and fixed a bug with instantiating JWT component

0.4.0 ** BREAKING CHANGE **

Apistar JWT updated to support Apistar >= 0.4. Pin to 0.3.3 for Apistar 0.3.x support

0.3.3

Update dev deps so we are using metadata 2.1 spec for pypi.

0.3.2

Updates to pin dependencies for Apistar 0.3.x and add Markdown rendering to pypi.org

0.3.1

Release for Apistar 0.3.x