I have been following the public documentation of polkadot API to deploy contract: https://polkadot.js.org/docs/api-contract/start/code

but I'm getting error Uncaught (in promise) TypeError: code.tx.new is not a function

here is my script:

import { ApiPromise, WsProvider } from "@polkadot/api";
import { CodePromise, ContractPromise } from "@polkadot/api-contract";
import { Keyring } from "@polkadot/keyring";

export const deployContract= async (wasm,abi,providerURL ="wss://rococo-contracts-rpc.polkadot.io",endowment=123456789,gasLimit=5000000n)=>{
    if(!wasm || !abi) {alert('wasm or abi not provided!'); return;}

    const provider = new WsProvider(providerURL);
    const api = await ApiPromise.create({ provider });
    const code = new CodePromise(api, abi, wasm);
    const keyring = new Keyring({ type: "sr25519" });
    const dataJsonAccount = {THIS_IS_JUST_PLACEHOLDER} 
    const tx = code.tx.new({gasLimit,storageDepositLimit:null})
    let address;
    const account = keyring.addFromJson(dataJsonAccount);

      const unsub = await tx.signAndSend(account, ({ contract, status }) => {
        if (status.isInBlock || status.isFinalized) {
          address = contract.address.toString();



Later I tried to print what is code.tx and I got result that there is a only construct function.

so I used that one like this:

          const tx = code.tx.construct({gasLimit,storageDepositLimit:null})

and it kinda worked, but I'm never getting my contract deployed for some reason. I'm getting this error:

          TypeError: Cannot read properties of undefined (reading 'address')

which means contract here:

          address = contract.address.toString();

is never deployed.

I also tried using Contracts-UI to deploy contract manually(by just uploading .contract, and it works.

What I'm missing, what I'm doing wrong?

1 Answer 1


Actually, this: smart contract function call error solved my question.

It seems that Polkadot documentation is not up to date.

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