Class TokenBridgeHomeSideClass

Returns

the minimum and maximum withdrawal limits as a string in token units (we assume 18 decimals, i.e. wei) for bridging a token to layer 1. This method is invoked with the layer 2 CPXD token address of the CPXD token being withdrawn.

Example

let { min, max } = await tokenBridge.getWithdrawalLimits(daiTokenAddress);

This call will invoke the token bridge contract to relay tokens from a layer 2 safe into the account specified in layer 1.

Example

let result = await tokenBridge.relayTokens(
  layer2SafeAddress,
  tokenAddress,
  layer1RecipientAddress,
  amountInWei
);

This call waits for the token bridge validators to perform their necessary signatures on the token bridge request from layer 2 to layer 1. After the bridge validators have signed the bridging request, this call will return a messageId, encodedData, and signatures for the bridging request. These items can then be used to claim the bridged tokens in layer 1.

This method is invoked with:

• The block height of layer 2 before the relayTokens call was initiated on the home side of the bridge. Get it with await layer2Web3.eth.getBlockNumber()
• The layer 2 transaction hash for the bridging transaction (the result of TokenBridgeHomeSide.relayTokens).

Example

let {
  messageId,
  encodedData,
  signatures
} = await tokenBridge.waitForBridgingValidation(fromBlock, txnHash);

This call will listen for a TokensBridgedToSafe event emitted by the TokenBridge home contract that has a recipient matching the specified address. The starting layer 2 block height should be captured before the call to relayTokens is made to begin bridging. It is used to focus the search and avoid matching on a previous bridging for this user.

Returns

promise that includes a web3 transaction receipt for the layer 2 transaction, from which you can obtain the transaction hash, ethereum events, and other details about the transaction https://web3js.readthedocs.io/en/v1.3.4/web3-eth-contract.html#id37.

Remarks

We use the subgraph to act as our indicator that bridging has completed, as this is the same mechanism that is populating the card wallet's displayed token balances

Example

let txnReceipt = await tokenBridge.waitForBridgingToLayer2Completed(
recipientAddress
startingBlockHeight,
);