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ABI

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Setup

For this example we’ll use tronweb to interact with the contract, but you can replace it with any Tron library of your choice.

Make sure to install it first:

yarn add tronweb

​
Interacting with the Contract

To execute a bridge transaction, call the depositWithId (TRC20) function as follows:

The commitmentId required by the contract corresponds to the quoteId returned by the API.

To obtain the commitmentId, first request a quote from the API, then commit it. The response will include the quoteId, which should be used as the commitmentId in the contract call.

See Quickstart for details.

import { TronWeb, providers } from 'tronweb'
import getBridgeConfigs from './getBridgeConfigs'

export const callTronBridgeContract = async (
  {
    token,
    amount,
    commitmentId,
    tronWalletAddress
  }) => {
  // See API Integration -> Fetch Bridge Configs for the full implementation
  const configs = await getBridgeConfigs()
  const chainConfig = configs[chain]

  // Replace with your wallet implementation
  const tronWeb = new TronWeb({
    fullHost: new providers.HttpProvider('https://api.shasta.trongrid.io'),
    // headers: { "TRON-PRO-API-KEY": 'your api key' }, -- if using a custom RPC
    privateKey: TRON_PRIVATE_KEY
  })
  const tokenConfig = chainConfig.tokens[token]
  const amountWithDecimals = +amount * 10 ** tokenConfig.decimals
  const tokenAddress = tokenConfig.address
  const bridgeContractAddress = chainConfig.contractAddress

  const {
    abi
  } = await tronWeb.trx.getContract(tokenAddress);

  const trc20Contract = tronWeb.contract(abi.entrys, tokenAddress);
  const allowance = await trc20Contract.allowance(tronWalletAddress, bridgeContractAddress).call();
  const formattedAllowance = parseInt(allowance, 10) / 10 ** tokenConfig.decimals;

  if (formattedAllowance < parseFloat(amount)) {
     await trc20Contract.approve(bridgeContractAddress, amountWithDecimals).send()
  }

  const {
    abi: bridgeAbi
  } = await tronWeb.trx.getContract(bridgeContractAddress);

  const contract = tronWeb.contract(bridgeAbi, bridgeContractAddress)
  const tx = await contract.depositWithId(tokenAddress, amountWithDecimals, `0x${commitmentId}`).send({shouldPollResponse: true})

  return tx
}
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