Icrc2_approve + agent-js

Developers JavaScript
1

My code looks like this:

const agent = new HttpAgent({ host: ‘https : // nns.ic0 . app’ }); //no spaces in url, i cudnt post links
agent.fetchRootKey();
const actor = await window.Actor2.createActor(idlFactory, {
agent: agent,
canisterId: “ryjl3-tyaaa-aaaaa-aaaba-cai”,
});

            // Call the icrc1_balance_of() function
            const balanceOfArgs = {
                owner: Principal.fromText(window.curuser.key),
                subaccount: [],
            };
            try {
                const balance = await actor.icrc1_balance_of(balanceOfArgs);
                console.log('Balance:', balance);
            } catch (error) {
                console.error('Error calling icrc1_balance_of():', error);
            }
            //the above function works and returns the proper balance

            
            // Call the icrc2_approve() function
            const approveArgs = {
                fee: [],
                memo: [],
                from_subaccount: [],
                created_at_time: [],
                amount: 50,
                expected_allowance: [],
                expires_at: [],
                spender: {
                    owner: Principal.fromText(window.curuser.key), //i also tried the canisterId of the canister i launched
                    subaccount: [],
                },
            };

            try {
                const approveResult = await actor.icrc2_approve(approveArgs);
                if (approveResult.Ok) {
                    console.log('Approve successful, transaction ID:', approveResult.Ok);
                } else {
                    console.error('Approve failed:', approveResult.Err);
                }
            } catch (error) {
                console.error('Error calling icrc2_approve():', error);
            }

Now the “icrc1_balance_of” call works and returns the proper balance… but icrc2_approve doesnt work. I’m logged into Internet Identity and it gives me this error:

Error calling icrc2_approve(): Error: Call was rejected:
Request ID: xxxxxxxxxxxxxxxx
Reject code: 4
Reject text: Anonymous principal cannot approve token transfers on the ledger.

at pollForResponse

does anyone know how to do icrc2_approve from javascript?

2

When you instantiate your actor, you need to pass in your identity that holds the tokens. Depending on what login method you’re using, there is generally a method to get the identity. For example, after you call the window.plug.connect There should be some more methods on window.plug that give you the identity.

3

You can use this library for easier interaction with ic agent and canisters.

you can find more about the library here Introducing @ic-reactor/core: Streamline Your Development on the Internet Computer

4

Thank, you were correct. I wasnt passing the identity argument when creating the actor

My new code looks like this and now it work:

            const authClient = await AuthClient.create();
            const identity = authClient.getIdentity();
            console.log('identity:', identity);

            //connect to nns-ledger with identity
            const jsagent = HttpAgent({ host: 'https://nns.ic0.app', identity: identity });
            jsagent.fetchRootKey();
            jsactor = await Actor.createActor(idlFactory, {
                agent: jsagent,
                canisterId: "ryjl3-tyaaa-aaaaa-aaaba-cai",
            });

One small question, do I have to do jsagent.fetchRootKey();? im not sure why i did that

5

in localhost deployment YES, in mainnet deployment NO.