README.md

description
Sending ERC20 tokens from your Loopring L2 to another Loopring L2 address.

Transfer

EndPoint

POST api/v3/transfer

Header

Field	Description	Example	Type	Required
X-API-KEY	ApiKey	"HlkcGxbqBeaF76j4rvPaOasyfPwnkQ6B6DQ6THZWbvrGxzEdulXQvOKLrRWZLnN"		Y
X-API-SIG	ECDSA Signature, pay attention the signature type, sign the ecdsa hash	"0xccf0a141fce2dc5cbbd4f802c52220e9e2ce260e86704d6258603eb346eefe2d4a450005c362b223b2842d087f7065ea5eee0314531adf6a580fce64c25dca81c02"		Y

Request

Query Param	Description	Example
exchange	exchangeAddress in exchange info
payerAddr	payer address
payerId	payer account ID	10110
payeeAddr	payee address
payeeId	payee account ID	10111，can set to 0 if dont have
token	tokenVolume，transfer tokenId and volume
maxFee	tokenVolume from offchain fee
storageId	offchainId of storage Id, sellTokenId is the transfer tokenId	1
validUntil	Timestamp for transfer to become invalid, seconds	normally current time + 2 months
eddsaSignature	eddsa signature of the transfer eddsa hash
memo	(Optional) memo
payPayeeUpdateAccount	(Optional) transfer to pay payee updateAccount fee , true or false, default is false	true
counterFactualInfo	(Optional) counterfactual Wallet Info, if it's a counterfactual wallet, need to pass the info

Response

Field	Description	Example	Type	Required
hash	The hash identifier set by the user at the time of submission, can use this hash to get the transfer info	"0x1d923ca7834dc90484fa2eb611f0f0bc7e741bb107007ebea19ba8caeab4f9d3"	string	Y
status	Whether the order was successfully submitted or not, please note, the user may query after a while to get the real process status, as most off-chain requests are asynchronously processed Allowable : ['received', 'processing', 'processed', 'failed']	"received"	string	Y
isIdempotent	Idempotent of submit transfer response, submit same transfer again idempotent will be true	"false"	boolean	Y

Model

TokenVolume

Wrapper object used to describe a token associated with a certain quantity.

Field	Description	Example	Type	Required
tokenId	The Loopring's token identifier.	0	integer	Y
volume	The volume of the token	"100000000000 0"	string	Y

counterFactualInfo

Counterfactual wallet information.

Field	Description	Example	Type	Required
walletFactory	Counterfactual wallet factory contract address	"0xbbbbca6a901c926f240b89eacb641d8aec7aeafd"	string	Y
walletOwner	Counterfactual wallet owner address, NOT the wallet address	"0xbbbbca6a901c926f240b89eacb641d8aec7aeafd"	string	Y
walletSalt	Salt to generate address from owner & other related info	"1"	string	Y

Compute ECDSA hash

const message = {
    from: data.payerAddr,
    to: data.payeeAddr,
    tokenID: data.token.tokenId,
    amount: data.token.volume,
    feeTokenID: data.maxFee.tokenId,
    maxFee: data.maxFee.volume,
    validUntil: data.validUntil,
    storageID: data.storageId,
  };
const typedData: EIP712TypedData = {
    types: {
      EIP712Domain: [
        { name: "name", type: "string" },
        { name: "version", type: "string" },
        { name: "chainId", type: "uint256" },
        { name: "verifyingContract", type: "address" },
      ],
      Transfer: [
        { name: "from", type: "address" },
        { name: "to", type: "address" },
        { name: "tokenID", type: "uint16" },
        { name: "amount", type: "uint96" },
        { name: "feeTokenID", type: "uint16" },
        { name: "maxFee", type: "uint96" },
        { name: "validUntil", type: "uint32" },
        { name: "storageID", type: "uint32" },
      ],
    },
    primaryType: "Transfer",
    domain: {
      name: "Loopring Protocol",
      version: "3.6.0",
      chainId: chainId,
      verifyingContract: data.exchange,
    },
    message: message,
  };

Compute EdDSA hash

const inputs = [
    new BN(ethUtil.toBuffer(request.exchange)).toString(),
    request.payerId,
    request.payeeId,
    request.token.tokenId,
    request.token.volume,
    request.maxFee.tokenId,
    request.maxFee.volume,
    new BN(ethUtil.toBuffer(request.payeeAddr)).toString(),
    0,
    0,
    request.validUntil,
    request.storageId,
];
const hasher = Poseidon.createHash(inputs.length + 1, 6, 53);
const hash = hasher(inputs).toString(10);