pip install bcrypt
pip install PyJWT

import bcrypt
password = "password"
encrypted_password = bcrypt.hashpw(password.encode("utf-8"), bcrypt.gensalt())  # str 객체, bytes로 인코드, salt를 이용하여 암호화
print(encrypted_password)  # bytes-string
print(encrypted_password.decode("utf-8"))  # str 객체  

b'17072bXEOimJ6msiHK7w/r7ayoO5W14cOVPLl8BPvmjhPJTWuo5RGRR.W6'
17072bXEOimJ6msiHK7w/r7ayoO5W14cOVPLl8BPvmjhPJTWuo5RGRR.W6

import bcrypt
encrypted_password = bcrypt.hashpw("password".encode("utf-8"), bcrypt.gensalt())
print(bcrypt.checkpw("password".encode("utf-8"), encrypted_password))
print(bcrypt.checkpw("pessword".encode("utf-8"), encrypted_password))

True
False

import jwt

json = {
    "id": "justkode",
    "password": "password"
}
encoded = jwt.encode(json, "secret", algorithm="HS256")  # str
decoded = jwt.decode(encoded, "secret", algorithms="HS256")  # dict

print(encoded)
print(decoded)

b'eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpZCI6Imp1c3Rrb2RlIiwicGFzc3dvcmQiOiJwYXNzd29yZCJ9.TKGlCElSgGthalfeTlbN_giphG9AC5y5HwCbz93N0cs'
{'id': 'justkode', 'password': 'password'}

from flask import Flask
from flask_restx import Resource, Api
from auth import Auth

app = Flask(__name__)
api = Api(
    app,
    version='0.1',
    title="JustKode's API Server",
    description="JustKode's Todo API Server!",
    terms_url="/",
    contact="justkode@kakao.com",
    license="MIT"
)

api.add_namespace(Auth, '/auth')

if __name__ == "__main__":
    app.run(debug=True, host='0.0.0.0', port=80)

import jwt
import bcrypt
from flask import request
from flask_restx import Resource, Api, Namespace, fields

users = {}

Auth = Namespace(
    name="Auth",
    description="사용자 인증을 위한 API",
)

user_fields = Auth.model('User', {  # Model 객체 생성
    'name': fields.String(description='a User Name', required=True, example="justkode")
})

user_fields_auth = Auth.inherit('User Auth', user_fields, {
    'password': fields.String(description='Password', required=True, example="password")
})

jwt_fields = Auth.model('JWT', {
    'Authorization': fields.String(description='Authorization which you must inclued in header', required=True, example="eyJ0e~~~~~~~~~")
})

@Auth.route('/register')
class AuthRegister(Resource):
    @Auth.expect(user_fields_auth)
    @Auth.doc(responses={200: 'Success'})
    @Auth.doc(responses={500: 'Register Failed'})
    def post(self):
        name = request.json['name']
        password = request.json['password']
        if name in users:
            return {
                "message": "Register Failed"
            }, 500
        else:
            users[name] = bcrypt.hashpw(password.encode("utf-8"), bcrypt.gensalt())  # 비밀번호 저장
            return {
                'Authorization': jwt.encode({'name': name}, "secret", algorithm="HS256")  # str으로 반환하여 return
            }, 200

@Auth.route('/login')
class AuthLogin(Resource):
    @Auth.expect(user_fields_auth)
    @Auth.doc(responses={200: 'Success'})
    @Auth.doc(responses={404: 'User Not Found'})
    @Auth.doc(responses={500: 'Auth Failed'})
    def post(self):
        name = request.json['name']
        password = request.json['password']
        if name not in users:
            return {
                "message": "User Not Found"
            }, 404
        elif not bcrypt.checkpw(password.encode('utf-8'), users[name]):  # 비밀번호 일치 확인
            return {
                "message": "Auth Failed"
            }, 500
        else:
            return {
                'Authorization': jwt.encode({'name': name}, "secret", algorithm="HS256") # str으로 반환하여 return
            }, 200

@Auth.route('/get')
class AuthGet(Resource):
    @Auth.doc(responses={200: 'Success'})
    @Auth.doc(responses={404: 'Login Failed'})
    def get(self):
        header = request.headers.get('Authorization')  # Authorization 헤더로 담음
        if header == None:
            return {"message": "Please Login"}, 404
        data = jwt.decode(header, "secret", algorithms="HS256")
        return data, 200