Better transaction fee estimation

[gregdhill]

Use https://polkadot.js.org/docs/api/cookbook/tx/#how-do-i-estimate-the-transaction-fees

[sander2]

Separated into another ticket https://github.com/interlay/interbtc-ui/issues/1240 Related: it'd be a good idea to dry-run in advance to get quick feedback on failing transactions. I made this PoC about a year ago:

    let request_redeem = api.tx.redeem.requestRedeem(2000, {P2WPKHv0: '0x01197bcaf42e278fcca2b55275cd64b25d240e7c'}, vault_id);
    const transactionAPI = new DefaultTransactionAPI(api, userKeyring);

    let myNonce = await api.rpc.system.accountNextIndex(userKeyring.address);
    const signed = request_redeem.sign(userKeyring, { nonce:  myNonce});

    const result = await signed.dryRun(transactionAPI.getAccount()!);

    // A technically valid but failing transaction returns Ok(Err(...))
    const resultOk = result.isOk && result.asOk.isOk;

    console.log("isOk", resultOk);

And you can get the fees with

const paymentInfo = await signed.paymentInfo(transactionAPI.getAccount()!);
console.log("fee", paymentInfo.partialFee.toNumber());

[peterslany]

This ticket's scope was reduced and dry-running should be added separately https://github.com/interlay/interbtc-ui/issues/1240

[github-actions[bot]]

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