[FIXED] Writing a SIMPLE flask page using Keycloak OIDC

Issue

I have had a lot of trouble finding a concise example for what I need.

I have a working Keycloak server at https://auth.mycompany.com. (not the real company name, of course) I have a flask server at http://testapp.mycompany.com.

All I need to do is have a simple page with a login flow that connects to my Keycloak server. As it turns out, all the Keycloak extensions are abandoned and poorly documented. There is flask_oidc, pyoidc, etc. However, the documentation I can find online is really not great. I have looked through a lot of github repos and struggled through a lot of thickly-accented youtube videos, but have yet to find an example of a Flask (Django also acceptable) app that simply and concisely implements an OIDC login flow. I even tried ChatGPT and it gave me several examples, none of which worked. I understand the OAuth2.0 and OIDC standards, and have read their source documents, but I have utterly failed at finding a boilerplate implementation of these things to start my hands-on-keyboard work.

Can someone please, please show me a very minimal example of an extremely basic Flask or Django app that would connect to my Keycloak server. I will gladly continue researching on my own to build upon it, but I can't seem to get it started.

I tried googling until I reached the edge of madness. I have tried numerous repos which literally did not function. I was told fictions by ChatGPT.

Solution

The structure folder is here. In your keycloak server, you must create a client connect to have client_id and client_secret_key

In server/constants/KeyCloakConstants.py

KEYCLOAK_SERVER_URL = os.getenv(
    "KEYCLOAK_SERVER_URL", "http://keycloak/auth/"
)
KEYCLOAK_REALM_NAME = os.getenv("KEYCLOAK_REALM_NAME", "user-dev")
# client
KEYCLOAK_CLIENT_ID = os.getenv("KEYCLOAK_CLIENT_ID", "client-service")
KEYCLOAK_CLIENT_SECRET_KEY = os.getenv(
    "KEYCLOAK_CLIENT_SECRET_KEY", "jGlenvHtelkBtSS6zsi72prZQeoAmPxy"
)

In server/extension.py

from server.constants import KeyCloakConstants as kcl
from keycloak import KeycloakOpenID

keycloak_client = KeycloakOpenID(
    server_url=kcl.KEYCLOAK_SERVER_URL,
    realm_name=kcl.KEYCLOAK_REALM_NAME,
    client_id=kcl.KEYCLOAK_CLIENT_ID,
    client_secret_key=kcl.KEYCLOAK_CLIENT_SECRET_KEY,
)

In server/services/KeycloakService.py

from server.extensions import keycloak_client

class KeycloakClientService:
    @classmethod
    def login_user(cls, data):
        token = keycloak_client.token(
            username=data.get("username"),
            password=data.get("password"),
        )
        return token

In server/controllers/AuthController.py

from flask import jsonify
from server.services.KeycloakService import KeycloakClientService

auth_api = Blueprint("auth_api", __name__)

@auth_api.route("/login", methods=["POST"])
def login_user():
    """
    `param`
        :body:
            username: String
            password: String
    `return`
        :body: access_token, expires_in, token_type
    """
    data = request.json
    token = KeycloakClientService.login_user(data)
    return jsonify(output)

Here is only the sample for using keycloak in flask. In your server, You need more to handle all case such as when error request from keycloak, incorrect user

Answered By - TanThien