Sending Transactions

Confirm you have:

  • Connected to Midgard or THORNode
  • Located the latest vault (and router) for the chain
  • Prepared the transaction details (and memo)
  • Checked the network is not halted for your transaction

You are ready to make the transaction and swap via THORChain.

UTXO Chains

⚠️ THORChain does NOT currently support BTC Taproot. User funds will be lost if sent to or from a taproot address!

  • Ensure the address type is supported
  • Send the transaction with Asgard vault as VOUT0
  • Pass all change back to the VIN0 address in a subsequent VOUT e.g. VOUT1
  • Include the memo as an OP_RETURN in a subsequent VOUT e.g. VOUT2
  • Use a high enough gas_rate to be included
  • Do not send below the dust threshold (10k Sats BTC, BCH, LTC, 1m DOGE), exhaustive values can be found on the Inbound Addresses endpoint
  • Do not send funds that are part of a transaction with more than 10 outputs

Warning

Inbound transactions should not be delayed for any reason else there is risk funds will be sent to an unreachable address. Use standard transactions, check the Inbound_Address before sending and use the recommended gas rate to ensure transactions are confirmed in the next block to the latest Inbound_Address.

Info

Memo limited to 80 bytes on BTC, BCH, LTC and DOGE. Use abbreviated options and THORNames where possible.

Warning

Do not use HD wallets that forward the change to a new address, because THORChain IDs the user as the address in VIN0. The user must keep their VIN0 address funded for refunds.

Danger

Override randomised VOUT ordering; THORChain requires specific output ordering. Funds using wrong ordering are very likely to be lost.

EVM Chains

https://gitlab.com/thorchain/thornode/-/blob/develop/chain/ethereum/contracts/THORChain_Router.sol

depositWithExpiry(vault, asset, amount, memo, expiry)
  • If ERC20, approve the router to spend an allowance of the token first
  • Send the transaction as a depositWithExpiry() on the router
  • Vault is the Asgard vault address, asset is the token address to swap, memo as a string
  • Use an expiry which is +60mins on the current time (if the tx is delayed, it will get refunded). The timestamp is in seconds (Solidity's block.timestamp).
  • Use a high enough gas_rate to be included, otherwise the tx will get stuck

Info

ETH is 0x0000000000000000000000000000000000000000

Danger

ETH is sent and received as an internal transaction. Your wallet may not be set to read internal balances and transactions.

Danger

Do not send assets from a smart contract (including smart contract wallets) without adding your contract to the whitelist. As a security measure, Thorchain ignores transactions coming from unknown smart contracts, resulting in a loss of funds.

BFT Chains

  • Send the transaction to the Asgard vault
  • Include the memo
  • Only use the base asset as the choice for gas asset

THORChain

To initiate a $RUNE -> $ASSET swap a MsgDeposit must be broadcasted to the THORChain blockchain. The MsgDeposit does not have a destination address, and has the following properties. The full definition can be found here.

MsgDeposit{
    Coins:  coins,
    Memo:   memo,
    Signer: signer,
}

If you are using Javascript, CosmJS is the recommended package to build and broadcast custom message types. Here is a walkthrough.

Code Examples (Javascript)

  1. Generate codec files. To build/broadcast native transactions in Javascript/Typescript, the protobuf files need to be generated into js types. The below script uses pbjs and pbts to generate the types using the relevant files from the THORNode repo. Alternatively, the .js and .d.ts files can be downloaded directly from the XChainJS repo.

    #!/bin/bash
    
    # this script checks out thornode master and generates the proto3 typescript buindings for MsgDeposit and MsgSend
    
    MSG_COMPILED_OUTPUTFILE=src/types/proto/MsgCompiled.js
    MSG_COMPILED_TYPES_OUTPUTFILE=src/types/proto/MsgCompiled.d.ts
    
    TMP_DIR=$(mktemp -d)
    
    tput setaf 2; echo "Checking out https://gitlab.com/thorchain/thornode  to $TMP_DIR";tput sgr0
    (cd $TMP_DIR && git clone https://gitlab.com/thorchain/thornode)
    
    # Generate msgs
    tput setaf 2; echo "Generating $MSG_COMPILED_OUTPUTFILE";tput sgr0
    yarn run pbjs -w commonjs  -t static-module $TMP_DIR/thornode/proto/thorchain/v1/common/common.proto $TMP_DIR/thornode/proto/thorchain/v1/x/thorchain/types/msg_deposit.proto $TMP_DIR/thornode/proto/thorchain/v1/x/thorchain/types/msg_send.proto $TMP_DIR/thornode/third_party/proto/cosmos/base/v1beta1/coin.proto -o $MSG_COMPILED_OUTPUTFILE
    
    tput setaf 2; echo "Generating $MSG_COMPILED_TYPES_OUTPUTFILE";tput sgr0
    yarn run pbts  $MSG_COMPILED_OUTPUTFILE -o $MSG_COMPILED_TYPES_OUTPUTFILE
    
    tput setaf 2; echo "Removing $TMP_DIR/thornode";tput sgr0
    rm -rf $TMP_DIR
    
  2. Using @cosmjs build/broadcast the TX.

    const {
      DirectSecp256k1HdWallet,
      Registry,
    } = require("@cosmjs/proto-signing");
    const {
      defaultRegistryTypes: defaultStargateTypes,
      SigningStargateClient,
    } = require("@cosmjs/stargate");
    const { stringToPath } = require("@cosmjs/crypto");
    const bech32 = require("bech32-buffer");
    
    const { MsgDeposit } = require("./types/MsgCompiled").types;
    
    async function main() {
      const myRegistry = new Registry(defaultStargateTypes);
      myRegistry.register("/types.MsgDeposit", MsgDeposit);
    
      const signerMnemonic = "mnemonic here";
      const signerAddr = "thor1...";
    
      const signer = await DirectSecp256k1HdWallet.fromMnemonic(signerMnemonic, {
        prefix: "thor", // THORChain prefix
        hdPaths: [stringToPath("m/44'/931'/0'/0/0")], // THORChain HD Path
      });
    
      const client = await SigningStargateClient.connectWithSigner(
        "https://rpc.ninerealms.com/",
        signer,
        { registry: myRegistry },
      );
    
      const memo = `=:BNB/BNB:${signerAddr}`; // THORChain memo
    
      const msg = {
        coins: [
          {
            asset: {
              chain: "THOR",
              symbol: "RUNE",
              ticker: "RUNE",
            },
            amount: "100000000", // Value in 1e8 (100000000 = 1 RUNE)
          },
        ],
        memo: memo,
        signer: bech32.decode(signerAddr).data,
      };
    
      const depositMsg = {
        typeUrl: "/types.MsgDeposit",
        value: MsgDeposit.fromObject(msg),
      };
    
      const fee = {
        amount: [],
        gas: "50000000", // Set arbitrarily high gas limit; this is not actually deducted from user account.
      };
    
      const response = await client.signAndBroadcast(
        signerAddr,
        [depositMsg],
        fee,
        memo,
      );
      console.log("response: ", response);
    
      if (response.code !== 0) {
        console.log("Error: ", response.rawLog);
      } else {
        console.log("Success!");
      }
    }
    
    main();
    

Native Transaction Fee

As of ADR-009, the native transaction fee for $RUNE transfers or inbound swaps is USD-denominated, but ultimately paid in $RUNE, which means the fee is dynamic. Interfaces should pull the native transaction fee from THORNode before each new transaction is built/broadcasted.

THORNode Network Endpoint: /thorchain/network

{
  ...
  "native_outbound_fee_rune": "2000000", // (1e8) Outbound fee for $Asset -> $RUNE swaps
  "native_tx_fee_rune": "2000000", // (1e8) Fee for $RUNE transfers or $RUNE -> $Asset swaps
  ...
  "rune_price_in_tor": "354518918", // (1e8) Current $RUNE price in USD
  ...
}

The native transaction fee is automatically deducted from the user's account for $RUNE transfers and inbound swaps. Ensure the user's balance exceeds tx amount + native_tx_fee_rune before broadcasting the transaction.