Implementing JWT Authentication in Flask

1pip install Flask Flask-JWT-Extended passlib
2

1from flask import Flask
2from flask_jwt_extended import JWTManager
3
4app = Flask(__name__)
5app.config['JWT_SECRET_KEY'] = 'your_secret_key'
6jwt = JWTManager(app)
7

1from flask import request, jsonify
2from flask_jwt_extended import create_access_token, jwt_required, get_jwt_identity
3from passlib.hash import sha256_crypt
4
5users = {}  # Placeholder for user data (e.g., stored in database)
6blacklisted_tokens = set()
7
8@app.route('/register', methods=['POST'])
9def register():
10    data = request.get_json()
11    username = data.get('username')
12    password = data.get('password')
13    hashed_password = sha256_crypt.hash(password)
14    users[username] = hashed_password
15    return jsonify({'message': 'User registered successfully'}), 201
16
17@app.route('/login', methods=['POST'])
18def login():
19    data = request.get_json()
20    username = data.get('username')
21    password = data.get('password')
22    if username in users and sha256_crypt.verify(password, users[username]):
23        access_token = create_access_token(identity=username)
24        return jsonify({'access_token': access_token}), 200
25    else:
26        return jsonify({'message': 'Invalid username or password'}), 401
27
28@app.route('/logout', methods=['POST'])
29@jwt_required()
30def logout():
31    jti = get_jwt()['jti']  # Get the unique identifier for the JWT token
32    blacklisted_tokens.add(jti)  # Add the token to the blacklist
33    return jsonify({'message': 'User logged out successfully'}), 200
34

1@app.route('/protected', methods=['GET'])
2@jwt_required()
3def protected():
4    jti = get_jwt()['jti']
5    if jti in blacklisted_tokens:
6        return jsonify({'message': 'Token has been revoked'}), 401
7    else:
8        identity = get_jwt_identity()
9        return jsonify(logged_in_as=identity), 200
10

1if __name__ == '__main__':
2    app.run(debug=True)
3

1curl -X POST -H "Content-Type: application/json" -d '{"username":"your_username", "password":"your_password"}' http://localhost:5000/register
2

1curl -X POST -H "Content-Type: application/json" -d '{"username":"your_username", "password":"your_password"}' http://localhost:5000/login
2

1curl -X POST -H "Authorization: Bearer your_access_token" http://localhost:5000/logout
2

1curl -X GET -H "Authorization: Bearer your_access_token" http://localhost:5000/protected
2