Impossible to convert undefined to Principal

salmanwaseem007 · May 14, 2024, 11:35am

Hello guys

Error: Impossible to convert undefined to Principal.

Situation: I want to pull logged in user principal ID in the backed. I’m trying to call a backend shared query function after a user is logged in and get this error, if I try to use the backend actor created after login with a new agent.
If i use a normal actor, without a logged in user principal, the call goes fine but I get the anonyms user principal in the backed, which is expected

I’m aware that I’m facing an issue which is already discussed in this forum but the suggestions provided are not helping me or perhaps I’m missing something.

Repo: GitHub - salmanwaseem007/ic_app_new
Front end code: ic_app_new/src/icp_app_new_frontend/src/App.jsx at main · salmanwaseem007/ic_app_new · GitHub
Backend code: ic_app_new/src/icp_app_new_backend/main.mo at main · salmanwaseem007/ic_app_new · GitHub

I have verified the backend canister ID is matching between process.env.CANISTER_ID_ICP_APP_NEW_BACKEND in the chrome and the canister ID itself.

I have also updated by DFX and created a brand new app with it and copied the app code to the new app from old one to the new one without touching anything else.

DFX version: 0.20.0

b3hr4d · May 14, 2024, 12:06pm

The error probably comes from the environment handling in your app. Try passing the canisterId as hardcoded:

backendActor = createActor(backend_idl, { agent, canisterId: "bkyz2-fmaaa-aaaaa-qaaaq-cai" });

And one suggestion: just use @ic-reactor/react. You will be impressed by its ease of use and features.

salmanwaseem007 · May 14, 2024, 12:39pm

still getting the same error. here the the code

github.com

salmanwaseem007/ic_app_new/blob/main/src/icp_app_new_frontend/src/App.jsx#L60


      
          async function handleAuthenticated(authClient) {
            const identity = authClient.getIdentity();
            // Using the identity obtained from the auth client, we can create an agent to interact with the IC.  
            const agent = new HttpAgent({ identity });
            // Using the interface description of our webapp, we create an actor that we use to call the service methods.  
            // backendActor = createActor(process.env.GREET_BACKEND_CANISTER_ID, {
            //   agent,
            // });
            backendActor = createActor(backend_idl, { agent, canisterId: "bkyz2-fmaaa-aaaaa-qaaaq-cai" });
          
            await backendActor.getUserPrincipal('Hi')
              .then((response) => {
                console.log(response);
              })
              .catch(error => {
                console.error(error);
              });
          
            const _principal = identity.getPrincipal().toString();
            console.log("logged in user principal", _principal);
            setIsAuthenticated(true);

b3hr4d · May 14, 2024, 12:53pm

I guess you are creating actor in a wrong way!
If you are using the default declarations files that generated using dfx, you should initialize actor like this createActor(canisterId, options = {})

salmanwaseem007 · May 14, 2024, 1:01pm

it worked. thank you

Topic		Replies	Views
Error when calling canister method from React app Developers	8	1712	November 14, 2021
Imposible to convert undefined to principal when trying to call a canister from backend Language Support Motoko , Wasm , Education	1	234	November 16, 2023
Error: “Impossible to convert undefined to Principal.” Motoko	8	704	August 3, 2023
I'm getting 'Error: Impossible to convert undefined to Principal' when calling motoko code Developers	1	1400	May 24, 2022
Sending front-end Principal to caller Language Support	3	35	July 10, 2024

Impossible to convert undefined to Principal

Related topics