Flask-restful API Authorization. Access current_identity inside decorator

My current solution looks like:

@app.before_request
def detect_something():
    header = request.headers.get('Authorization')
    if header:
        _, token = header.split()
        request.identity = identity(jwt.decode(token,
                                               app.config['SECRET_KEY']))

After it we can access identity in decorator via request.identity. And I removed current_identity everywhere from code. It's still messy way.

Here is the combination of quickstarts of both Flask-JWT and Flask-Restful.

from flask import Flask
from flask_restful import Resource, Api, abort
from functools import wraps

app = Flask(__name__)
api = Api(app)

from flask_jwt import JWT, jwt_required, current_identity
from werkzeug.security import safe_str_cmp

class User(object):
    def __init__(self, id, username, password):
        self.id = id
        self.username = username
        self.password = password

    def __str__(self):
        return "User(id='%s')" % self.id

users = [
    User(1, 'user1', 'abcxyz'),
    User(2, 'user2', 'abcxyz'),
]

username_table = {u.username: u for u in users}
userid_table = {u.id: u for u in users}

def authenticate(username, password):
    user = username_table.get(username, None)
    if user and safe_str_cmp(user.password.encode('utf-8'), password.encode('utf-8')):
        return user

def identity(payload):
    user_id = payload['identity']
    return userid_table.get(user_id, None)

app.config['SECRET_KEY'] = 'super-secret'

jwt = JWT(app, authenticate, identity)


def checkuser(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        if current_identity.username == 'user1':
            return func(*args, **kwargs)
        return abort(401)
    return wrapper

class HelloWorld(Resource):
    decorators = [checkuser, jwt_required()]
    def get(self):
        return {'hello': current_identity.username}

api.add_resource(HelloWorld, '/')

if __name__ == '__main__':
    app.run(debug=True)

POST

{
    "username": "user1",
    "password": "abcxyz"
}

To localhost:5000/auth and get the access_token in response.

Then GET localhost:5000/ with header

Authorization: JWT `the access_token value above`

You would get

{
  "hello": "user1"
}

if you try to access localhost:5000/ with the JWT token of user2, you would get 401.

The decorators are wrapped in this way:

for decorator in self.decorators:
    resource_func = decorator(resource_func)

https://github.com/flask-restful/flask-restful/blob/master/flask_restful/init.py#L445

So the later one in the decorators array gets to run earlier.

For more reference:

https://github.com/rchampa/timetable/blob/master/restful/users.py

https://github.com/mattupstate/flask-jwt/issues/37