Skip to main content

🌉 Celer

Celer Bridge (cBridge) is a cross-chain bridge that helps in moving assets from one chain to the other with lower costs. Please refer to the Official Documentation for detailed information on Celer.

This module provides scripts to help you interact/integrate cBridge into your applications robustly without explicitly digging into cBridge technical documentation. Basic features included in the package are:

Pool Based Transfer (Liquidity)

  1. PoolTransfer : Liquidity transfer from one chain to another by locking funds in source chain and releasing funds in destination chain.
  2. PoolTransfer Refund : Request refund for any failed pool transfer transactions.

Canonical Mapping Transfer (Asset)

  1. MintCanonical Token : Mint or Deposit tokens on the source chain
  2. MintCanonical Token Refund : Request refund for any failed mint transactions
  3. BurnCanonical Token : Burn or withdraw tokens on pegged chain
  4. BurnCanonical Token Refund : Request refund for any failed burn transactions

Follow the below steps to try out the above features using the sdk.

Installation

npm install @kaiachain/kss-bridges-celer --save

Quick Start

There are two modules in the celer bridge starter kit.

  1. BridgeSDK provides the implementation and examples of bridge use-cases.
  2. CoreBridgeSDK exposes methods of celer core functions to write custom snippets.
import BridgeSDK from '@kaiachain/kss-bridges-celer';
import CoreBridgeSDK from '@kaiachain/kss-bridges-celer/core';

or

const BridgeSDK = require('@kaiachain/kss-bridges-celer');
const CoreBridgeSDK = require('@kaiachain/kss-bridges-celer/core');

NOTE: Please make sure the wallet provided has enough balance in source/destination to perform the transactions.

1. PoolBased Transfer

You will be able to transfer your funds using cBridge's pool based transfer method. It's a liquidity based transfer in which your funds are locked at source_chain (sending chain) and released on destination_chain (receiving chain) from a pool of liquidity available on the destination chain.

BridgeSDK.poolTransfer(transferObj)

Parameters

transferObj - Object

  • CBRIDGE_GATEWAY_URL - string From here you can get Testnet & Mainnet cBridge's Gateway URLs.
  • WALLET_ADDRESS - string address of your account.
  • PRIVATE_KEY - string private key of your account.
  • SRC_CHAIN_ID - number chain ID of source-chain. From here you can get the chain ID of your source-chain.
  • DST_CHAIN_ID - number chain ID of destination-chain. From here you can get the chain ID of your source-chain.
  • SRC_CHAIN_RPC - string RPC endpoint of your source-chain (the chain from where you want to send your tokens to).
  • TOKEN_SYMBOL - string SYMBOL of your token, which you want to move from source chain to destination. You can get SYMBOLS of supported tokens with the pair of chains you've mentioned above at cBridge web interface
  • AMOUNT - string amount of token, you want to move from source to destination chain Ex: 1 USDC
  • SLIPPAGE_TOLERANCE - number slippage amount you can tolerate while transferring your tokens from source to destination chain. Please go through celer slippage_tolerance for more info.
  • CONFIRMATIONS - number set the number of Blocks confirmations you want a transaction should achieve before considering it mined. Provie Max value of source and destination chain confirmations.

Result

Promise transferId - string Transfer ID for tracking the transaction. To track the status or refund transaction if stuck

Example

const BridgeSDK = require('@klaytn/kss-bridges-celer')

let CBRIDGE_GATEWAY_URL = "https://cbridge-v2-test.celer.network"
let WALLET_ADDRESS = "0x5Bc0635a264B94A8662e0F2887d76F8E5925F837"
let PRIVATE_KEY= "private key here" // Account should contain enough USDC tokens. Get Test USDC from https://test-cbridge-v2.celer.network/5/80001/USDC.
let SRC_CHAIN_ID= 5
let DST_CHAIN_ID= 80001
let SRC_CHAIN_RPC= "https://ethereum-goerli-rpc.allthatnode.com"
let TOKEN_SYMBOL= "USDC"
let AMOUNT= "1"
let SLIPPAGE_TOLERANCE= 550000 // 
let CONFIRMATIONS= 6

// View the transaction in the Celer UI (https://test-cbridge-v2.celer.network/5/80001/USDC)
BridgeSDK.poolTransfer(
        CBRIDGE_GATEWAY_URL,
        WALLET_ADDRESS,
        PRIVATE_KEY,
        SRC_CHAIN_ID,
        DST_CHAIN_ID,
        SRC_CHAIN_RPC,
        TOKEN_SYMBOL,
        AMOUNT,
        SLIPPAGE_TOLERANCE,
        CONFIRMATIONS
).then(transferId => {
    console.log("TransferId =", transferId);
});

1.1. Refund PoolBased Transfer

Due to any reason if your funds / assets were not released on destination_chain, don't worry you can get them back on source_chain by submitting refund request.

BridgeSDK.poolTransferRefund(transferObj)

Parameters

Object - transferObj

  • CBRIDGE_GATEWAY_URL - string From here you can get Testnet & Mainnet cBridge's Gateway URLs.
  • WALLET_ADDRESS - string address of your account.
  • PRIVATE_KEY - string private key of your account
  • SRC_CHAIN_ID - number chain ID of source-chain. From here you can get the chain ID of your source-chain
  • SRC_CHAIN_RPC - string RPC endpoint of your source-chain (the chain from where you want to send your tokens to )
  • TOKEN_SYMBOL - string SYMBOL of your token, which you want to move from source chain to destination. You can get SYMBOLS of supported tokens with the pair of chains you've mentioned above at cBridge web interface
  • AMOUNT - string amount of token, you want to move from source to destination chain Ex: 1 USDC
  • SLIPPAGE_TOLERANCE - number slippage amount you can tolerate while transferring your tokens from source to destination chain. Please go through celer slippage_tolerance for more info.
  • CONFIRMATIONS - number set the number of Blocks confirmations you want a transaction should achieve before considering it mined. Provie Max value of source and destination chain confirmations.
  • TRANSFER_ID - string Transfer ID received while performing the transfer.

Result

Promise transactionReceipt - object blockchain transaction receipt

Example

let BridgeSDK = require("@klaytn/kss-bridges-celer");

let CBRIDGE_GATEWAY_URL = "https://cbridge-v2-test.celer.network"
let WALLET_ADDRESS = "0x5Bc0635a264B94A8662e0F2887d76F8E5925F837"
let PRIVATE_KEY= "private key here"
let SRC_CHAIN_ID= 5
let SRC_CHAIN_RPC= "https://ethereum-goerli-rpc.allthatnode.com"
let TOKEN_SYMBOL= "USDC"
let AMOUNT= "1"
let SLIPPAGE_TOLERANCE= 550000
let CONFIRMATIONS= 6
let TRANSFER_ID = "0x64e0c583b60dc68390119dcc968cd27b4c2f1c92bdeec22fbab145235e7d0e01" // Transfer ID received while performing the transfer

BridgeSDK.poolTransferRefund(
        CBRIDGE_GATEWAY_URL,
        WALLET_ADDRESS,
        PRIVATE_KEY,
        SRC_CHAIN_ID,
        SRC_CHAIN_RPC,
        TOKEN_SYMBOL,
        AMOUNT,
        SLIPPAGE_TOLERANCE,
        TRANSFER_ID,
        CONFIRMATIONS
).then(contractReceipt => {
    console.log("Transaction Hash: "+contractReceipt.transactionHash)
});

2. MintCanonicalToken

You will be able to transfer your assets using cBridge's Mint Canonical Token method. It's a traditional method in which your assets are locked at source_chain (sending chain) and minted on destination_chain (receiving chain).

BridgeSDK.mintCanonicalToken(transferObj)

Parameters

Object - transferObj

  • CBRIDGE_GATEWAY_URL - string From here you can get Testnet & Mainnet cBridge's Gateway URLs.
  • WALLET_ADDRESS - string address of your account.
  • PRIVATE_KEY - string private key of your account
  • SRC_CHAIN_ID - number chain ID of source-chain. From here you can get the chain ID of your source-chain
  • DST_CHAIN_ID - number chain ID of destination-chain. From here you can get the chain ID of your source-chain
  • SRC_CHAIN_RPC - string RPC endpoint of your source-chain (the chain from where you want to send your tokens to other chain)
  • TOKEN_SYMBOL - string Pegged token address on the pegged chain
  • AMOUNT - string amount of token, you want to move from source to destination chain Ex: 1 USDC
  • CONFIRMATIONS - number set the number of Blocks confirmations you want a transaction should achieve before considering it mined. Provie Max value of source and destination chain confirmations.

Result

Promise depositId - string deposit id

Example

let BridgeSDK = require("@klaytn/kss-bridges-celer");

let CBRIDGE_GATEWAY_URL = "https://cbridge-v2-test.celer.network"
let WALLET_ADDRESS = "0x5Bc0635a264B94A8662e0F2887d76F8E5925F837"
let PRIVATE_KEY= "private key here"
let SRC_CHAIN_ID= 5
let DST_CHAIN_ID= 71401
let SRC_CHAIN_RPC= "https://ethereum-goerli-rpc.allthatnode.com"
let TOKEN_SYMBOL= "USDC"
let AMOUNT= "1"
let CONFIRMATIONS= 6

BridgeSDK.mintCanonicalToken(
        CBRIDGE_GATEWAY_URL,
        WALLET_ADDRESS,
        PRIVATE_KEY,
        SRC_CHAIN_ID,
        DST_CHAIN_ID,
        SRC_CHAIN_RPC,
        TOKEN_SYMBOL,
        AMOUNT,
        CONFIRMATIONS
).then(depositId => {
    console.log("DepositId =", depositId);
});

2.1. Refund mintCanonicalToken

Due to any reason if your funds / assets were not minted on destination_chain, don't worry you can get them back on source_chain by submitting refund request.

BridgeSDK.mintCanonicalTokenRefund(transferObj)

Parameters

Object - transferObj

  • CBRIDGE_GATEWAY_URL - string From here you can get Testnet & Mainnet cBridge's Gateway URLs.
  • WALLET_ADDRESS - string address key of your account
  • PRIVATE_KEY - string private key of your account
  • SRC_CHAIN_ID - number chain ID of source-chain. From here you can get the chain ID of your source-chain
  • DST_CHAIN_ID - number chain ID of destination-chain. From here you can get the chain ID of your source-chain
  • SRC_CHAIN_RPC - string RPC endpoint of your source-chain (the chain from where you want to send your tokens to other chain)
  • SLIPPAGE_TOLERANCE - number slippage amount you can tolerate while transferring your tokens from source to destination chain. Please go through celer slippage_tolerance for more info.
  • TOKEN_SYMBOL - string SYMBOL of your token, which you want to move from source chain to destination. You can get SYMBOLS of supported tokens with the pair of chains you've mentioned above at cBridge web interface
  • SLIPPAGE_TOLERANCE - number slippage amount you can tolerate while transferring your tokens from source to destination chain. Please go through celer slippage_tolerance for more info.
  • DEPOSIT_ID - string Deposit ID received while performing the mint transfer.
  • AMOUNT - string amount of token, you want to move from source to destination chain Ex: 1 USDC
  • CONFIRMATIONS - number set the number of Blocks confirmations you want a transaction should achieve before considering it mined. Provie Max value of source and destination chain confirmations.

Result

Promise transactionReceipt - object blockchain transaction receipt

Example

let BridgeSDK = require("@klaytn/kss-bridges-celer");

let CBRIDGE_GATEWAY_URL = "https://cbridge-v2-test.celer.network"
let WALLET_ADDRESS = "0x5Bc0635a264B94A8662e0F2887d76F8E5925F837"
let PRIVATE_KEY= "private key here"
let SRC_CHAIN_ID= 5
let DST_CHAIN_ID= 71401
let SRC_CHAIN_RPC= "https://ethereum-goerli-rpc.allthatnode.com"
let SLIPPAGE_TOLERANCE = 550000
let TOKEN_SYMBOL= "USDC"
let DEPOSIT_ID = "deposit Id of a mint transaction to be reverted if stuck"
let AMOUNT= "1"
let CONFIRMATIONS= 6

BridgeSDK.mintCanonicalTokenRefund(
        CBRIDGE_GATEWAY_URL,
        WALLET_ADDRESS,
        PRIVATE_KEY,
        SRC_CHAIN_ID,
        DST_CHAIN_ID,
        SRC_CHAIN_RPC,
        SLIPPAGE_TOLERANCE,
        TOKEN_SYMBOL,
        DEPOSIT_ID,
        AMOUNT,
        CONFIRMATIONS
).then(contractReceipt => {
    console.log("Transaction Hash: "+contractReceipt.transactionHash)
});

3. BurnCanonicalToken

You will also be able to withdraw your assets from destination chain to source chain (the chain from where you sent tokens earlier) using cBridge's Burn Canonical Token method. It's a method in which your assets get burnt at source_chain ( the chain from where you're withdrawing your assets) and released on destination_chain (the chain on which you want to receive you withdrawn assets).

BridgeSDK.burnCanonicalToken(transferObj)

NOTE: Amount for burn should always be between min and max burn values of pegged burn contract

  • you can get min & max burn amount of given pegged token cBridge contract
  • for example at Godwoken testnet for the token of USDC: 0x4Ea08DCA142F103ac2D5FF95F1d376712C5EF5a9
  • you can get maxBurn & minBurn amount from this Godwoken cBridge contract.
  • you need to provide USDC address as a parameter in above-mentioned functions (same for other chains & pegged tokens)

Parameters

Object - transferObj

  • CBRIDGE_GATEWAY_URL - string From here you can get Testnet & Mainnet cBridge's Gateway URLs.
  • SRC_CHAIN_RPC - string RPC endpoint of your source-chain (the chain from where you want to send your tokens to other chain)
  • WALLET_ADDRESS - string address key of your account
  • PRIVATE_KEY - string private key of your account
  • SRC_CHAIN_ID - number chain ID of source-chain. From here you can get the chain ID of your source-chain
  • DST_CHAIN_ID - number chain ID of destination-chain. From here you can get the chain ID of your source-chain
  • TOKEN_SYMBOL - string Pegged token address on the pegged chain
  • AMOUNT - string amount of token, you want to move from source to destination chain Ex: 1 USDC
  • CONFIRMATIONS - number set the number of Blocks confirmations you want a transaction should achieve before considering it mined. Provie Max value of source and destination chain confirmations.

Result

Promise burnId - string burn id to track the status or refund transaction if stuck

Example

let BridgeSDK = require("@klaytn/kss-bridges-celer");

let CBRIDGE_GATEWAY_URL = "https://cbridge-v2-test.celer.network"
let SRC_CHAIN_RPC= "https://godwoken-testnet-v1.ckbapp.dev"
let WALLET_ADDRESS = "0x5Bc0635a264B94A8662e0F2887d76F8E5925F837"
let PRIVATE_KEY= "private key here"
let SRC_CHAIN_ID= 71401
let DST_CHAIN_ID= 5
let TOKEN_SYMBOL= "USDC"
let AMOUNT= "21" // Amount must be between min, max burn configuration and have enough balance. Please refer to the Note section above for more details.
let CONFIRMATIONS= 6

BridgeSDK.burnCanonicalToken(
        CBRIDGE_GATEWAY_URL,
        SRC_CHAIN_RPC,
        WALLET_ADDRESS,
        PRIVATE_KEY,
        SRC_CHAIN_ID,
        DST_CHAIN_ID,
        TOKEN_SYMBOL,
        AMOUNT,
        CONFIRMATIONS
).then(burnId => {
    console.log("BurnId =", burnId);
});

3.1. Refund burnCanonicalToken

Due to any reason if your funds / assets were not released on destination_chain, don't worry you can get them back on source_chain by submitting refund request.

BridgeSDK.burnCanonicalTokenRefund(transferObj)

Parameters

Object - transferObj

  • CBRIDGE_GATEWAY_URL - string From here you can get Testnet & Mainnet cBridge's Gateway URLs.
  • WALLET_ADDRESS - string address key of your wallet account
  • SRC_CHAIN_ID - number chain ID of source-chain. From here you can get the chain ID of your source-chain
  • DST_CHAIN_ID - number chain ID of destination-chain. From here you can get the chain ID of your source-chain
  • SRC_CHAIN_RPC - string RPC endpoint of your source-chain (the chain from where you want to send your tokens to other chain)
  • PRIVATE_KEY - string private key of your wallet / account
  • SLIPPAGE_TOLERANCE - number slippage amount you can tolerate while transferring your tokens from source to destination chain. Please go through celer slippage_tolerance for more info.
  • TOKEN_SYMBOL - string SYMBOL of your token, which you want to move from source chain to destination. You can get SYMBOLS of supported tokens with the pair of chains you've mentioned above at cBridge web interface
  • BURN_ID - string Burn ID received while performing the burn transfer.
  • AMOUNT - string amount of token, you want to move from source to destination chain Ex: 21 USDC
  • CONFIRMATIONS - number set the number of Blocks confirmations you want a transaction should achieve before considering it mined. Provie Max value of source and destination chain confirmations.

Result

Promise transactionReceipt - object blockchain transaction receipt

Example

let BridgeSDK = require("@klaytn/kss-bridges-celer");

let CBRIDGE_GATEWAY_URL = "https://cbridge-v2-test.celer.network"
let WALLET_ADDRESS = "0x5Bc0635a264B94A8662e0F2887d76F8E5925F837"
let SRC_CHAIN_ID= 71401
let DST_CHAIN_ID= 5
let SRC_CHAIN_RPC= "https://godwoken-testnet-v1.ckbapp.dev"
let PRIVATE_KEY= "private key here"
let SLIPPAGE_TOLERANCE = 550000
let TOKEN_SYMBOL= "USDC"
let BURN_ID = "burnId of a previous burn transaction to be reverted if stuck"
let AMOUNT= "21"
let CONFIRMATIONS= 6

BridgeSDK.burnCanonicalTokenRefund(
        CBRIDGE_GATEWAY_URL,
        WALLET_ADDRESS,
        SRC_CHAIN_ID,
        DST_CHAIN_ID,
        SRC_CHAIN_RPC,
        PRIVATE_KEY,
        SLIPPAGE_TOLERANCE,
        TOKEN_SYMBOL,
        BURN_ID,
        AMOUNT,
        CONFIRMATIONS
).then(contractReceipt => {
    console.log("Transaction Hash: "+contractReceipt.transactionHash)
});

Reference Docs