Signing - Cosmos

Pre-Requisite: You have generated the transaction context, payload, and Msgs (see prior pages).

Signing with Keplr

const signTxn = async (
    context: TxContext,
    payload: TransactionPayload,
    protoMsgs: any[],
    simulate: boolean
) => {
    if (!account) {
        throw new Error('Account does not exist');
    }
    const { sender } = context;
    await window.keplr?.enable(chainId);

    let signatures = [new Uint8Array(Buffer.from('0x', 'hex'))];
    if (!simulate) {
        const signResponse = await window?.keplr?.signDirect(
            chainId,
            sender.address,
            {
                bodyBytes: payload.signDirect.body.toBinary(),
                authInfoBytes: payload.signDirect.authInfo.toBinary(),
                chainId: chainId,
                accountNumber: new Long(sender.accountNumber),
            },
            {
                preferNoSetFee: true,
            }
        );

        if (!signResponse) {
            throw new Error('No signature returned from Keplr');
        }

        signatures = [
            new Uint8Array(
                Buffer.from(signResponse.signature.signature, 'base64')
            ),
        ];
    }

    const hexSig = Buffer.from(signatures[0]).toString('hex');

    const txBody = createTxBroadcastBody(context, protoMsgs, hexSig);
    return txBody;
};

Output

This will leave you with a variable which is to be submitted to a running blockchain node. See Broadcast to a Node.