Version: Next

Set up trustline

To set up a trustline, make sure that a user instance is loaded into the library.

1. Request for establishing a trustline#

Trustlines consist of bi-directional credit agreements. That means, that they have to be accepted by both parties. The first step to establish a trustline is therefore to create an initial request or proposal to the counterparty.

const tlNetwork1 = new TLNetwork()
// Create and/or load user 1 ...
const networkAddress = "0xf8E191d2cd72Ff35CB8F012685A29B31996614EA"
const counterpartyAddress = "0xcE2D6f8bc55A61428D32947bC9Bc7F2DE1640B18"
// Prepare a transaction to request a trustline update
const {
} = await tlNetwork1.trustline.prepareUpdate(
100, // Proposed credit limit given to counterparty
200 // Proposed credit limit received from counterparty
console.log("Transaction fees: ", ethFees)
console.log("Delegation fees: ", delegationFees)
// Sign and relay the transaction
const txHash = await tlNetwork1.trustline.confirm(rawTx)
console.log("Transaction hash: ", txHash)

The initiator creates a request where he is willing to lend a maximal denomination of 100 to the user with the address counterpartyAddress in the currency network with the address networkAddress. He also proposes that he is willing to owe a maximal denomination of 200 to the counterparty. If the walletType is ethers, delegationFees are undefined.

2. Accepting a trustline request#

In the next step the counterparty has to accept the request. Note that in the example below the loaded user is the counterparty of step 1.

const tlNetwork2 = new TLNetwork()
// Create and/or load user 2 ...
const networkAddress = "0xf8E191d2cd72Ff35CB8F012685A29B31996614EA"
// Retrieve latest request from step 1
const requests = await tlNetwork2.trustline.getRequests(networkAddress)
const latestRequest = requests[requests.length - 1]
const initiatorAddress = latestRequest.from
const creditlineGivenToInitiator = latestRequest.received.value
const creditlineReceivedFromInitiator = latestRequest.given.value
const { rawTx } = await tlNetwork2.trustline.prepareAccept(
// sign and relay the transaction
const txHash = await tlNetwork2.trustline.confirm(rawTx)
console.log("Transaction hash: ", txHash)

The counterparty of step 1 first fetches all trustline requests in the currency network. The prepareAccept function is then called where the attributes given and received have to be from the point of view of the caller. So in our case the counterparty or receiver of the initial request.

NOTE: All numerical values have to be provided in their largest unit. For example, if the currency network has two decimals, the values have to be in a format like 1.25.