Advanced Patterns - Cosmos Docs

Offline Signing

You can sign transactions without an RPC connection. This is useful for air-gapped signing or pre-signing transactions:

const client = await SigningStargateClient.offline(wallet);

const txRaw = await client.sign(
  signerAddress,
  messages,
  fee,
  "memo",
  {
    accountNumber: 42,
    sequence: 7,
    chainId: "cosmoshub-4",
  },
);

When signing offline, you must provide explicitSignerData since the client cannot query the chain for account number, sequence, and chain ID.

Inspecting a Signed Transaction

You can decode a signed transaction to inspect its contents:

import { decodeTxRaw } from "@cosmjs/proto-signing";
import { TxRaw } from "cosmjs-types/cosmos/tx/v1beta1/tx";

const txRaw = await client.sign(address, messages, fee, "memo");
const txBytes = TxRaw.encode(txRaw).finish();
const decoded = decodeTxRaw(txBytes);

// decoded.body.messages — the encoded messages
// decoded.authInfo — fee and signer info
// decoded.signatures — the raw signatures

IBC Transfer

Send tokens across chains using IBC:

import { MsgTransfer } from "cosmjs-types/ibc/applications/transfer/v1/tx";
import { Height } from "cosmjs-types/ibc/core/client/v1/client";

const msg = {
  typeUrl: "/ibc.applications.transfer.v1.MsgTransfer",
  value: MsgTransfer.fromPartial({
    sourcePort: "transfer",
    sourceChannel: "channel-0",
    token: { denom: "uatom", amount: "1000000" },
    sender: senderAddress,
    receiver: "osmo1recipient...",
    timeoutHeight: Height.fromPartial({
      revisionNumber: BigInt(1),
      revisionHeight: BigInt(currentHeight + 100),
    }),
  }),
};

const result = await client.signAndBroadcast(senderAddress, [msg], "auto");

Checking Transaction Results

import { isDeliverTxFailure, isDeliverTxSuccess } from "@cosmjs/stargate";

const result = await client.signAndBroadcast(address, messages, "auto");

if (isDeliverTxSuccess(result)) {
  console.info("Success:", result.transactionHash);
} else if (isDeliverTxFailure(result)) {
  const errorLog = result.events.map((e) => `${e.type}: ${JSON.stringify(e.attributes)}`).join("\n");
  console.error("Failed with code", result.code, ":", errorLog);
}