Sign and Broadcast Tx w/ PrivateKey - Injective

main.ts

import Mnemonic from "bitcore-mnemonic"
import { 
  BaseAccount,
  ChainRestAuthApi,
  createTransactionAndCosmosSignDoc,
  PrivateKey,
  TxRestApi,
  InjectiveDirectEthSecp256k1Wallet,
  hexToBuff,
  createTxRawFromSigResponse,
  MsgExecuteContractCompat,
  DEFAULT_DERIVATION_PATH
} from '@injectivelabs/sdk-ts'

(async function() {
  // Seed phrase - Mnemonic
  const mnemonic = "[MNEMONIC]"

  // 1. Derive private key hex from mnemonic
  // const privateKeyHex = (new Mnemonic(mnemonic)).toHDPrivateKey().derive(DEFAULT_DERIVATION_PATH).privateKey.toBuffer().toString("hex")
  
  // 2. Use private key hex directly
  const privateKeyHex = "[PRIVATE_KEY_HEX]"

  // Private key from hex
  const privateKey = PrivateKey.fromHex(privateKeyHex)
  const bech32Address = privateKey.toBech32()

  console.log("INJ Signer: Executing tx with address", bech32Address)
  
  // Astroport INJ-USDT pool injective testnet address
  const INJ_USDT_POOL_ADDRESS = "inj13u7zxehmatgj4yhwgjcw5nf8hux067hx8wlx84";
  // USDT injective testnet address
  const USDT_ADDRESS = "peggy0x87aB3B4C8661e07D6372361211B96ed4Dc36B1B5";
  
  // Create messages
  const messages = [
    MsgExecuteContractCompat.fromJSON({
      sender: bech32Address,
      contractAddress: INJ_USDT_POOL_ADDRESS,
      msg: {
        swap: {
          offer_asset: {
            amount: "100000000", // 100 USDT
            info: { native_token: { denom: USDT_ADDRESS } },
          },
          max_spread: "0.1",
          belief_price: "1185115746.301293090000000000", // Hardcoded from latest simulate query
        },
      },
      funds: [{ denom: USDT_ADDRESS, amount: "100000000" }], // 100 USDT
    })
  ];
  
  // Injective testnet
  const CHAIN_ID = "injective-888";
  // Injective testnet REST API URL
  const INJECTIVE_REST_URL = "[INJECTIVE_REST_URL]";
  
  // Prepare tx
  const chainRestAuthApi = new ChainRestAuthApi(INJECTIVE_REST_URL);
  const accountDetailsResponse = await chainRestAuthApi.fetchAccount(bech32Address);
  const baseAccount = BaseAccount.fromRestApi(accountDetailsResponse);
  const preparedTx = await createTransactionAndCosmosSignDoc({
    pubKey: privateKey.toPublicKey().toBase64(),
    chainId: CHAIN_ID,
    message: messages.map((msg) => msg.toDirectSign()),
    sequence: baseAccount.sequence,
    accountNumber: baseAccount.accountNumber,
  });

  // Setup tx rest api
  const txRestApi = new TxRestApi(INJECTIVE_REST_URL);

  // Simulate tx
  try {
    const txRaw = preparedTx.txRaw;
    await txRestApi.simulate(txRaw);
  } catch(e) {
    console.log("INJ Signer: Simulate tx error");
    throw e;
  }

  try {
    // Sign tx
    const wallet = await InjectiveDirectEthSecp256k1Wallet.fromKey(hexToBuff(privateKeyHex));
    const directSignResponse = await wallet.signDirect(bech32Address, preparedTx.cosmosSignDoc);
    const signing = createTxRawFromSigResponse(directSignResponse);

    // Broadcast tx
    const broadcast = await txRestApi.broadcast(signing);

    if (broadcast.code !== 0) {
      throw new Error(broadcast.rawLog);
    }

    // Fetch broadcasted tx
    const response = await txRestApi.fetchTxPoll(broadcast.txHash, 15000);
    console.log("INJ Signer: Tx response", response);
  } catch(e) {
    console.log("INJ Signer: Broadcast tx error");
    throw e;
  }
})();