dapp.md

DApp Integration

Trust extends WalletConnect with aditional methods to support multi-chain dApps. Currently, you can get all accounts and sign transactions for any blockchain implements signJSON method in wallet core

Supported Coins

• Binance Chain
• Ethereum and forks
• Cosmos, Kava and other sdk based chains
• Tezos
• Nano
• Filecoin (until mainnet)

Getting started

To use Trust additional methods, you just need to install:

npm install --save @walletconnect/client @walletconnect/qrcode-modal

Initiate Connection

Before you can sign transactions, you have to initiate a connection to a WalletConnect bridge server, and handle all possible states: (code snippet below is copied from https://docs.walletconnect.org/quick-start/dapps/client#initiate-connection)

import WalletConnect from "@walletconnect/client";
import QRCodeModal from "@walletconnect/qrcode-modal";

// Create a connector
const connector = new WalletConnect({
  bridge: "https://bridge.walletconnect.org", // Required
  qrcodeModal: QRCodeModal,
});

// Check if connection is already established
if (!connector.connected) {
  // create new session
  connector.createSession();
}

// Subscribe to connection events
connector.on("connect", (error, payload) => {
  if (error) {
    throw error;
  }

  // Get provided accounts and chainId
  const { accounts, chainId } = payload.params[0];
});

connector.on("session_update", (error, payload) => {
  if (error) {
    throw error;
  }

  // Get updated accounts and chainId
  const { accounts, chainId } = payload.params[0];
});

connector.on("disconnect", (error, payload) => {
  if (error) {
    throw error;
  }

  // Delete connector
});

Get Accounts

Once you have walletconnect client set up, you will be able to get user's accounts:

const request = connector._formatRequest({
    method: 'get_accounts',
});

connector
  ._sendCallRequest(request)
  .then(result => {
    // Returns the accounts
    console.log(result);
  })
  .catch(error => {
    // Error returned when rejected
    console.error(error);
  });

The result is an array with following structure:

[
  {
    network: number,
    address: string
  }
]

Sign Transaction

Once you have the account list, you will be able to sign a transaction, please note that the json structure is based on WalletCore's proto messages, we suggest using protobuf.js or @trustwallet/wallet-core to generate it properly.

const network = 118; // Atom (SLIP-44)
const account = accounts.find((account) => account.network === network);
// Transaction structure based on Trust's protobuf messages.
const tx = {
accountNumber: "1035",
  chainId: "cosmoshub-2",
  fee: {
    amounts: [
      {
        denom: "uatom",
        amount: "5000"
      }
    ],
    gas: "200000"
  },
  sequence: "40",
  sendCoinsMessage: {
    fromAddress: account.address,
    toAddress: "cosmos1zcax8gmr0ayhw2lvg6wadfytgdhen25wrxunxa",
    amounts: [
      {
        denom: "uatom",
        amount: "100000"
      }
    ]
  }
};

const request = connector._formatRequest({
    method: 'trust_signTransaction',
    params: [
        {
            network,
            transaction: JSON.stringify(tx),
        },
    ],
});

connector
  ._sendCallRequest(request)
  .then(result => {
    // Returns transaction signed in json or encoded format
    console.log(result);
  })
  .catch(error => {
    // Error returned when rejected
    console.error(error);
  });

The result can be either a string JSON or an HEX encoded string. For Atom, the result is JSON:

{
    "tx": {
        "fee": {
            "amount": [{
                "amount": "5000",
                "denom": "uatom"
            }],
            "gas": "200000"
        },
        "memo": "",
        "msg": [{
            "type": "cosmos-sdk/MsgSend",
            "value": {
                "amount": [{
                    "amount": "100000",
                    "denom": "uatom"
                }],
                "from_address": "cosmos135qla4294zxarqhhgxsx0sw56yssa3z0f78pm0",
                "to_address": "cosmos1zcax8gmr0ayhw2lvg6wadfytgdhen25wrxunxa"
            }
        }],
        "signatures": [{
            "pub_key": {
                "type": "tendermint/PubKeySecp256k1",
                "value": "A+mYPFOMSp6IYyXsW5uKTGWbXrBgeOOFXHNhLGDsGFP7"
            },
            "signature": "m10iqKAHQ5Ku5f6NcZdP29fPOYRRR+p44FbGHqpIna45AvYWrJFbsM45xbD+0ueX+9U3KYxG/jSs2I8JO55U9A=="
        }],
        "type": "cosmos-sdk/MsgSend"
    }
}