错误默认的 Firebase 应用已经存在。 这意味着您多次调用 initialize_app() 而没有提供应用程序名称作为

Question

i try to connnect at my firebase application and i have an error

This is my code:

@event_routes.route('/scanner/events', methods=['GET'], cors=True)
def get_scanner_events() -> Response:
    
    try:
        id_token = event_routes.current_request.headers["IdToken"]
    except KeyError:
        return Response(body={"message": "missing id token for authentication"}, status_code=400,
                        headers={"Content-Type": "application/json"})


  
   # add json content (dict) 
    try:
        GOOGLE_APPLICATION_CREDENTIALS = json.loads(os.getenv("GOOGLE_APPLICATION_CREDENTIALS", ""))
        TEST_GOOGLE_PRIVATE_KEY = os.getenv("TEST_GOOGLE_PRIVATE_KEY", "").replace(r'\n', '\n')
        GOOGLE_APPLICATION_CREDENTIALS['private_key'] = TEST_GOOGLE_PRIVATE_KEY 

        cred = firebase_admin.credentials.Certificate(GOOGLE_APPLICATION_CREDENTIALS)
        firebase_app = firebase_admin.initialize_app(credential=cred)
        value = firebase_admin.auth.verify_id_token(id_token) 
        # print("made it here")
        print(firebase_app.project_id)
        
    except auth.InvalidIdTokenError as e:
        print("InvalidIdTokenError")
        return Response(body={"message": "invalid id token"}, status_code=400,
                        headers={"Content-Type": "application/json"})

this is my error:

ERROR The default Firebase app already exists. This means you called initialize_app() more than once without providing an app name as the second argument. In most cases you only need to call initialize_app() once. But if you do want to initialize multiple apps, pass a second argument to initialize_app() to give each app a unique name.

I checked on Inte.net but i am quite lost.

Thanks for yours answers!

Answer 1

As the error says, you need to initialize Firebase only once.

firebase_app = firebase_admin.initialize_app(credential=cred)

This statement runs every time /scanner/events route is called. Instead you should move this statement out of any route and initialize only once at the top. For example:

# Define this at the top 
GOOGLE_APPLICATION_CREDENTIALS = json.loads(os.getenv("GOOGLE_APPLICATION_CREDENTIALS", ""))
TEST_GOOGLE_PRIVATE_KEY = os.getenv("TEST_GOOGLE_PRIVATE_KEY", "").replace(r'\n', '\n')
GOOGLE_APPLICATION_CREDENTIALS['private_key'] = TEST_GOOGLE_PRIVATE_KEY 

cred = firebase_admin.credentials.Certificate(GOOGLE_APPLICATION_CREDENTIALS)

# This must run only once
firebase_app = firebase_admin.initialize_app(credential=cred)
        
@event_routes.route('/scanner/events', methods=['GET'], cors=True)
def get_scanner_events() -> Response:
    
    try:
        id_token = event_routes.current_request.headers["IdToken"]
    except KeyError:
        return Response(body={"message": "missing id token for authentication"}, status_code=400,
                        headers={"Content-Type": "application/json"})

   # add json content (dict) 
    try:
        value = firebase_admin.auth.verify_id_token(id_token) 
        # print("made it here")
        print(firebase_app.project_id)
        
    except auth.InvalidIdTokenError as e:
        print("InvalidIdTokenError")
        return Response(body={"message": "invalid id token"}, status_code=400,
                        headers={"Content-Type": "application/json"})