okorienev / flask-jwtlogin

flask extension to handle user login in APIs

Flask-jwtlogin quickstart

flask-jwtlogin is a lightweight flask extension to handle users in REST APIs
What it offers to you:

• jwt_required decorator to check jwt presence in current request
• generate_jwt func to get token with user identifier encrypted
• load_user for manual loading user from request using callback function
• current_user proxy

How to use it?

flask-jwtlogin can be simply installed with pip:

pip install flask-jwtlogin

First of all, you need some configuration:

{
    'JWT_HEADER_NAME': 'your_header_name',  #header to retrieve token from request
    'JWT_SECRET_KEY': 'you will never guess me',  #keep it secret
    'JWT_ENCODING_ALGORITHM': 'HS256',  #look at algorithms present in PyJWT
    'JWT_LIFETIME': 3600 * 24 * 7  # in seconds
}

Then create a login manager instance.

login_manager = jwtl.JWTLogin()  #creating instance
login_manager.init_app(app)  #importing configuration

You need to set callback function loading users from your storage and to inherit your user class from KnownUser

class User(jwtl.KnownUser):
    """Example of class representing user"""
    def __init__(self, name, age, identifier):
        self.name = name
        self.age = age
        self.identifier = identifier
        
user_storage = [  #sample storage
    User("Tom", 22, "AF5F123"),
    User("Jim", 25, "FFF1832"),
    User("Peter", 18, "CB0CA931")]


@login_manager.user_loader
def load_user(identifier):
    """example of user loader function"""
    for i in user_storage:
        if i.identifier == identifier:
            return i

Sample route to generate user tokens:

@app.route('/get-token/<name>')
def get_token(name):
    """Sample view that returns jwt"""
    for i in user_storage:
        if i.name == name:
            return jsonify(login_manager.generate_jwt_token(i.identifier))  
    abort(401)

Sample route to load user:

@app.route('/login/')
@login_manager.jwt_required
def login():
    """View that loads user from jwt present in request"""
    user = login_manager.load_user()
    return user.identifier

the example above shows the way of manual user loading but module also provides suitable proxy The jwt_required decorator adds user loaded from request to flask.g and current_user loads it.

@app.route('/current_user_test/')
@login_manager.jwt_required
def test_current_user():
    return jwtl.current_user.identifier

flask.g lives inside application context (new for each request) so it's safe to store values in API there