Enable your tokens in CCIP (Lock & Mint): Register from an EOA using Hardhat

Hardhat (Lock & Mint)

Foundry (Lock & Mint)

This tutorial will guide you through the process of enabling your own tokens in CCIP using Hardhat. You will learn how to deploy tokens, set up a Lock & Release token pool on the source blockchain, and a Burn & Mint token pool on the destination blockchain. After that, you will register them in CCIP and configure them without needing manual intervention. Finally, you will test the Lock & Mint token handling mechanism, where tokens are locked on the source blockchain and an equivalent amount is minted on the destination blockchain.

We will cover the following key steps:

1. Deploying Tokens: You will deploy your BurnMintERC677 tokens on the Avalanche Fuji and Arbitrum Sepolia testnets.

2. Deploying Token Pools: Once your tokens are deployed, you will deploy LockReleaseTokenPool on Avalanche Fuji and BurnMintTokenPool token pools on Arbitrum Sepolia. These pools are essential for testing the Lock & Mint token transfer mechanism: Locking the tokens on the source blockchain and then minting an equivalent amount of tokens on the destination blockchain. Each token will be linked to a pool, which will manage token transfers and ensure proper handling of assets across chains.

3. Claiming Mint and Burn Roles: You will claim the mint and burn roles for the destination token pool, allowing it to mint and burn tokens during cross-chain transfers.

4. Claiming and Accepting the Admin Role: This is a two-step process:

   1. You will call the RegistryModuleOwnerCustom contract's registerAdminViaOwner function to register your EOA as the token admin. This role is required to enable your token in CCIP.

   2. Once claimed, you will call the TokenAdminRegistry contract's acceptAdminRole function to complete the registration process.

5. Linking Tokens to Pools: You will call the TokenAdminRegistry contract's setPool function to associate each token with its respective token pool.

6. Configuring Token Pools: You will call the applyChainUpdates function on your token pools to configure each pool by setting cross-chain transfer parameters, such as token pool rate limits and enabled destination chains.

7. Minting Tokens: You will call the mint function to mint tokens on Avalanche Fuji for your EOA. These tokens will later be used to test cross-chain transfers to Arbitrum Sepolia.

8. Transferring Tokens: Finally, you will transfer tokens from Avalanche Fuji to Arbitrum Sepolia using CCIP. You will have the option to pay CCIP fees in either LINK tokens or native gas tokens.

By the end of this tutorial, you will have successfully deployed, registered, configured, and enabled your tokens and token pools for use in CCIP.

Before You Begin

1. Make sure you have Node.js v18 or above installed. If not, install Node.js v18:
   Download Node.js 18 if you don't have it installed. Optionally, you can use the nvm package to switch between Node.js versions:

   nvm use 18
   

   Verify that the correct version of Node.js is installed:

   node -v
   

   Example output:

   $ node -v
   v18.7.0
   

2. Clone the repository and navigate to the project directory:

   git clone https://github.com/smartcontractkit/smart-contract-examples.git
   cd smart-contract-examples/ccip/cct/hardhat
   

3. Install dependencies for the project:

   npm install
   

4. Compile the project:

   npm run compile
   

5. Encrypt your environment variables for higher security:
   The project uses @chainlink/env-enc to encrypt your environment variables at rest. Follow the steps below to configure your environment securely:

   1. Set an encryption password for your environment variables:

      npx env-enc set-pw
      

   2. Set up a .env.enc file with the necessary variables for Avalanche Fuji and Arbitrum Sepolia testnets. Use the following command to add the variables:

      npx env-enc set
      

      Variables to configure:

      • AVALANCHE_FUJI_RPC_URL: A URL for the Avalanche Fuji testnet. You can get a personal endpoint from services like Alchemy or Infura.
      • ARBITRUM_SEPOLIA_RPC_URL: A URL for the Arbitrum Sepolia testnet. You can sign up for a personal endpoint from Alchemy or Infura.
      • PRIVATE_KEY: The private key for your testnet wallet. If you use MetaMask, you can follow this guide to export your private key. Note: This key is required for signing transactions like token transfers.
      • ETHERSCAN_API_KEY: An API key from Etherscan to verify your contracts. You can obtain one from Etherscan.
      • ARBISCAN_API_KEY: An API key from Arbiscan to verify your contracts on Arbitrum. See this guide to get one from Arbiscan.

6. Fund your EOA with LINK and native gas tokens:
   Make sure your EOA has enough LINK and native gas tokens on Avalanche Fuji and Arbitrum Sepolia to cover transaction fees. You can use the Chainlink faucets to get testnet tokens.

Tutorial

Deploy Tokens

In this step, you will use the deployToken.ts task to deploy tokens on two testnets, Avalanche Fuji and Arbitrum Sepolia. Below is an explanation of the parameters used during deployment:

Deploy tokens, use the following commands, substituting the token name and symbol as needed:

1. Deploy the token on Avalanche Fuji:

   npx hardhat deployToken --name "BnM aem" --symbol BnMaem --decimals 18 --initialsupply 0 --withgetccipadmin false --verifycontract true --network avalancheFuji
   

   Example output:

   2024-10-09T00:30:55.806Z info: Deploying BurnMintERC677 contract to avalancheFuji
   2024-10-09T00:30:55.807Z info: Waiting 2 blocks for transaction 0x4485bff6e32118df8f05c64514719456e0be3a4980a7a63c40cfbf046829bf96 to be confirmed...
   2024-10-09T00:30:58.992Z info: Token deployed to: 0xdbaDd1a728b45c85A34910aaCe81989087c95476
   2024-10-09T00:30:59.066Z info: Granting mint and burn roles to 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:31:03.891Z info: Verifying contract...
   Successfully submitted source code for contract
   @chainlink/contracts-ccip/src/v0.8/shared/token/ERC677/BurnMintERC677.sol:BurnMintERC677 at 0xdbaDd1a728b45c85A34910aaCe81989087c95476
   for verification on the block explorer. Waiting for verification result...
   
   Successfully verified contract BurnMintERC677 on the block explorer.
   https://testnet.snowtrace.io/address/0xdbaDd1a728b45c85A34910aaCe81989087c95476#code
   
   2024-10-09T00:31:21.917Z info: Token contract deployed and verified
   

2. Deploy the token on Arbitrum Sepolia:

   npx hardhat deployToken --name "BnM aem" --symbol BnMaem --decimals 18 --initialsupply 0 --withgetccipadmin false --verifycontract true --network arbitrumSepolia
   

   Example output:

   2024-10-09T00:31:28.032Z info: Deploying BurnMintERC677 contract to arbitrumSepolia
   2024-10-09T00:31:28.033Z info: Waiting 2 blocks for transaction 0xad9a8372b418ec9c762748ae753c954b763fa7fe460448cdfd3d4b901eb145d2 to be confirmed...
   2024-10-09T00:31:28.359Z info: Token deployed to: 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca
   2024-10-09T00:31:28.540Z info: Granting mint and burn roles to 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:31:30.541Z info: Verifying contract...
   The contract 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca has already been verified on the block explorer. If you're trying to verify a partially verified contract, please use the --force flag.
   https://sepolia.arbiscan.io/address/0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca#code
   
   2024-10-09T00:31:31.234Z info: Token contract deployed and verified
   

Deploy Token Pools

In this step, you will use the deployTokenPool.ts task to deploy token pools for the tokens on both testnets, Avalanche Fuji and Arbitrum Sepolia. You will deploy a Lock & Release token pool for your token on Avalanche Fuji and a Burn & Mint token pool for your token on Arbitrum Sepolia. Below is an explanation of the parameters used during deployment:

Deploy token pools using the following commands, replacing the token address with the one deployed in the previous step:

1. Deploy the Lock & Release token pool on Avalanche Fuji:

   npx hardhat deployTokenPool --tokenaddress 0xdbaDd1a728b45c85A34910aaCe81989087c95476 --pooltype lockRelease --verifycontract true --network avalancheFuji
   

   Example output:

   2024-10-09T00:32:59.396Z info: Waiting 2 blocks for transaction 0xa52f184097c41ee5f71b446f1f5789447dfbf13548ddc6683c238de79264fe54 to be confirmed...
   2024-10-09T00:33:08.207Z info: Token pool deployed to: 0xF06da00F65d9afD1419c5270b6Ef59234e083E3c
   2024-10-09T00:33:08.208Z info: Verifying contract...
   Successfully submitted source code for contract
   @chainlink/contracts-ccip/src/v0.8/ccip/pools/LockReleaseTokenPool.sol:LockReleaseTokenPool at 0xF06da00F65d9afD1419c5270b6Ef59234e083E3c
   for verification on the block explorer. Waiting for verification result...
   
   Successfully verified contract LockReleaseTokenPool on the block explorer.
   https://testnet.snowtrace.io/address/0xF06da00F65d9afD1419c5270b6Ef59234e083E3c#code
   
   2024-10-09T00:33:38.979Z info: Token pool contract deployed and verified
   

2. Deploy the Burn & Mint token pool on Arbitrum Sepolia:

   npx hardhat deployTokenPool --tokenaddress 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca --pooltype burnMint --verifycontract true --network arbitrumSepolia
   

   Example output:

   2024-10-09T00:33:46.754Z info: Waiting 2 blocks for transaction 0x8cc9f0d200a4197d8ba5224b91cea626fd229bf1883ca95739317965e534da2d to be confirmed...
   2024-10-09T00:33:47.210Z info: Token pool deployed to: 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd
   2024-10-09T00:33:47.211Z info: Granting mint and burn roles to 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd on token 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca
   2024-10-09T00:33:49.463Z info: Verifying contract...
   The contract 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd has already been verified on the block explorer. If you're trying to verify a partially verified contract, please use the --force flag.
   https://sepolia.arbiscan.io/address/0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd#code
   
   2024-10-09T00:33:49.982Z info: Token pool contract deployed and verified
   

Claim Admin

In this step, you will use the claimAdmin.ts task to register your EOA as the administrator for the deployed tokens on both testnets, Avalanche Fuji and Arbitrum Sepolia. This process involves calling the RegistryModuleOwnerCustom contract, which will fetch the token owner and set it up as the admin.

Below is an explanation of the parameters used during the admin claim process:

Claim the admin role by using the following commands, replacing the token address with the one you deployed in the previous steps:

1. Claim the admin role on Avalanche Fuji:

   npx hardhat claimAdmin --tokenaddress 0xdbaDd1a728b45c85A34910aaCe81989087c95476 --withccipadmin false --network avalancheFuji
   

   Example output:

   2024-10-09T00:35:07.908Z info: Current token owner: 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:35:07.908Z info: Claiming admin of 0xdbaDd1a728b45c85A34910aaCe81989087c95476 via owner() for signer 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:35:26.508Z info: Claimed admin of 0xdbaDd1a728b45c85A34910aaCe81989087c95476 tx: 0x66150c3ed2b4816de6142221293084a50c5e9058ad1df4107734cb9d2ba36f01
   

2. Claim the admin role on Arbitrum Sepolia:

   npx hardhat claimAdmin --tokenaddress 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca --withccipadmin false --network arbitrumSepolia
   

   Example output:

   2024-10-09T00:35:30.541Z info: Current token owner: 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:35:30.542Z info: Claiming admin of 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca via owner() for signer 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:35:33.140Z info: Claimed admin of 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca tx: 0x32120ac720ba847f2402b627c05d2c349ca1ed38ec3f562f47b73d5f9fb5b316
   

Accept Admin Role

In this step, you will use the acceptAdminRole.ts task to accept the admin role for the deployed tokens on both testnets, Avalanche Fuji and Arbitrum Sepolia. Once you have claimed the role, accepting the role finalizes your control over the token administration.

Below is an explanation of the parameters used during the admin role acceptance process:

Accept the admin role by using the following commands, replacing the token address with the one deployed in the previous steps:

1. Accept the admin role on Avalanche Fuji:

   npx hardhat acceptAdminRole --tokenaddress 0xdbaDd1a728b45c85A34910aaCe81989087c95476 --network avalancheFuji
   

   Example output:

   2024-10-09T00:36:10.863Z info: Accepted admin role for token 0xdbaDd1a728b45c85A34910aaCe81989087c95476 tx: 0x70c42eb7dce2bff46f28ffb9b6f500a632b9a8f4064cc3dba9f640f5bccb70e7
   

2. Accept the admin role on Arbitrum Sepolia:

   npx hardhat acceptAdminRole --tokenaddress 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca --network arbitrumSepolia
   

   Example output:

   2024-10-09T00:36:26.058Z info: Accepted admin role for token 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca tx: 0xd42c2fdec2d556c07b0c45654a39180d9555313d84fb3c7f5bfd308160eea054
   

Set Pool

In this step, you will use the setPool.ts task to link each token with its respective token pool on both testnets.

Below is an explanation of the parameters used during the pool setting process:

Link each token with its respective token pool by using the following commands, replacing the token and pool addresses with the ones you deployed in the previous steps:

1. Set the pool for Avalanche Fuji:

   npx hardhat setPool --tokenaddress 0xdbaDd1a728b45c85A34910aaCe81989087c95476 --pooladdress 0xF06da00F65d9afD1419c5270b6Ef59234e083E3c --network avalancheFuji
   

   Example output:

   2024-10-09T00:37:26.568Z info: Setting pool for token 0xdbaDd1a728b45c85A34910aaCe81989087c95476 to 0xF06da00F65d9afD1419c5270b6Ef59234e083E3c by 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:37:36.984Z info: Pool set for token 0xdbaDd1a728b45c85A34910aaCe81989087c95476 to 0xF06da00F65d9afD1419c5270b6Ef59234e083E3c
   

2. Set the pool for Arbitrum Sepolia:

   npx hardhat setPool --tokenaddress 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca --pooladdress 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd --network arbitrumSepolia
   

   Example output:

   2024-10-09T00:37:46.444Z info: Setting pool for token 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca to 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd by 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:37:48.785Z info: Pool set for token 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca to 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd
   

Configure Pool

In this step, you will use the applyChainUpdates.ts task to configure the token pools on each blockchain to enable cross-chain transfers between Avalanche Fuji and Arbitrum Sepolia. This involves linking the token pool on one blockchain to a corresponding pool on another blockchain, allowing cross-chain token transfers. You will interact with the TokenPool contract, specifically calling the applyChainUpdates() function to configure the cross-chain parameters and rate limits.

Below is an explanation of the parameters used during the pool configuration process:

Configure the pools using the following commands, replacing the pool, token, and remote pool addresses with those you deployed in the previous steps:

1. Configure the pool on Avalanche Fuji:

   npx hardhat applyChainUpdates --pooladdress 0xF06da00F65d9afD1419c5270b6Ef59234e083E3c --remotechain arbitrumSepolia --remotetokenaddress 0x8e72ad94Fa399EA74fbeD9B2851406F5eD585eca --remotepooladdress 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd --network avalancheFuji
   

   Example output:

   2024-10-09T00:38:53.595Z info: Applying chain update to pool at address: 0xF06da00F65d9afD1419c5270b6Ef59234e083E3c
   2024-10-09T00:39:07.150Z info: Chain update applied successfully
   

2. Configure the pool on Arbitrum Sepolia:

   npx hardhat applyChainUpdates --pooladdress 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd --remotechain avalancheFuji --remotetokenaddress 0xdbaDd1a728b45c85A34910aaCe81989087c95476 --remotepooladdress 0xF06da00F65d9afD1419c5270b6Ef59234e083E3c --network arbitrumSepolia
   

   Example output:

   2024-10-09T00:39:51.938Z info: Applying chain update to pool at address: 0x4Efc423A4eB0EDF79CebCF92731e1074ed8A0BFd
   2024-10-09T00:39:54.695Z info: Chain update applied successfully
   

Mint Tokens

In this step, you will use the mintTokens.ts task to mint tokens on Avalanche Fuji for your Externally Owned Account (EOA). Since you assigned mint and burn privileges to your EOA when deploying the tokens in the first step, you can now mint tokens for testing purposes. This is to ensure that you have enough tokens in your EOA to perform cross-chain transfers in the next step.

You will interact with the BurnMintERC677 token contract, specifically calling the mint() function to mint tokens to your EOA.

Below is an explanation of the parameters used during the minting process:

Mint tokens to your EOA using the following command, replacing the token address with the one you deployed in the previous steps:

1. Mint tokens on Avalanche Fuji:

   npx hardhat mintTokens --tokenaddress 0xdbaDd1a728b45c85A34910aaCe81989087c95476 --amount 1000000000000000000000 --network avalancheFuji
   

   Example output:

   2024-10-09T00:40:43.085Z info: Minting 1000000000000000000000 of BnMaem tokens to 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d
   2024-10-09T00:40:53.729Z info: Minted 1000000000000000000000 of BnMaem tokens to 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d - transaction hash: 0x2de281303a988bc84bf5c8e3af26823ba7d184f08ecb6bd18035c40513742e55
   2024-10-09T00:40:53.867Z info: Current balance of 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d is 1000000000000000000000 BnMaem
   

Transfer Tokens

In this step, you will use the transferTokens task to transfer tokens from Avalanche Fuji to Arbitrum Sepolia using CCIP. You have two options for paying CCIP fees: using LINK tokens or native gas tokens.

You will interact with the IRouterClient contract, specifically calling the ccipSend() function to initiate the token transfer.

Below is an explanation of the parameters used during the token transfer process:

Pay fees in LINK

Call the CCIP Router to transfer tokens from Avalanche Fuji to Arbitrum Sepolia, paying the CCIP fees in LINK tokens. Replace the token address, amount, receiver address, and blockchain with the appropriate values:

npx hardhat transferTokens --tokenaddress 0xdbaDd1a728b45c85A34910aaCe81989087c95476 --amount 100 --destinationchain arbitrumSepolia --receiveraddress 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d --network avalancheFuji

Example output:

2024-10-09T00:41:45.369Z info: Estimated fees: 33747943040184402
2024-10-09T00:41:45.372Z info: Approving 100 0xdbaDd1a728b45c85A34910aaCe81989087c95476 to 0xF694E193200268f9a4868e4Aa017A0118C9a8177
2024-10-09T00:41:59.175Z info: Approving 33747943040184402 LINK to 0xF694E193200268f9a4868e4Aa017A0118C9a8177
2024-10-09T00:42:04.408Z info: Transferring 100 of 0xdbaDd1a728b45c85A34910aaCe81989087c95476 to 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d on chain arbitrumSepolia with 33747943040184402 of LINK as fees
2024-10-09T00:42:08.216Z info: Transaction hash: 0xa504ab6c43bc69211cb4440421698237d73e66a377496294f5189cfbfa79abf1
2024-10-09T00:42:08.283Z info: ✅ Transferred 100 of 0xdbaDd1a728b45c85A34910aaCe81989087c95476 to 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d on chain arbitrumSepolia. Transaction hash: 0xa504ab6c43bc69211cb4440421698237d73e66a377496294f5189cfbfa79abf1 - CCIP message id: 0x3f76edda3fdd81726315c2e2d879a7294bbc9d10fcf1a51d14962406d193330d
2024-10-09T00:42:08.284Z info: Check status of message on https://ccip.chain.link/msg/0x3f76edda3fdd81726315c2e2d879a7294bbc9d10fcf1a51d14962406d193330d

Pay fees in native gas tokens

Call the CCIP Router to transfer tokens from Avalanche Fuji to Arbitrum Sepolia, paying the CCIP fees in native gas tokens. Replace the token address, amount, receiver address, and blockchain with the appropriate values:

npx hardhat transferTokens --tokenaddress 0xdbaDd1a728b45c85A34910aaCe81989087c95476 --amount 100 --destinationchain arbitrumSepolia --receiveraddress 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d --fee native --network avalancheFuji

Example output:

2024-10-09T00:42:50.643Z info: Estimated fees: 14949052354043163
2024-10-09T00:42:50.647Z info: Approving 100 0xdbaDd1a728b45c85A34910aaCe81989087c95476 to 0xF694E193200268f9a4868e4Aa017A0118C9a8177
2024-10-09T00:42:53.828Z info: Transferring 100 of 0xdbaDd1a728b45c85A34910aaCe81989087c95476 to 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d on chain arbitrumSepolia with 14949052354043163 of native token as fees
2024-10-09T00:43:03.482Z info: Transaction hash: 0xdeeb8d9accebf47c3b2e2266d2125710d051bf138a562b0fa5a5fac4d79f489d
2024-10-09T00:43:03.552Z info: ✅ Transferred 100 of 0xdbaDd1a728b45c85A34910aaCe81989087c95476 to 0x45C90FBb5acC1a5c156a401B56Fea55e69E7669d on chain arbitrumSepolia. Transaction hash: 0xdeeb8d9accebf47c3b2e2266d2125710d051bf138a562b0fa5a5fac4d79f489d - CCIP message id: 0xd6708ce17c43f1f4158b48a26708dbaeaf4224092bd8bb381147de27911c65b8
2024-10-09T00:43:03.552Z info: Check status of message on https://ccip.chain.link/msg/0xd6708ce17c43f1f4158b48a26708dbaeaf4224092bd8bb381147de27911c65b8

Your tokens have been locked on the token pool on Avalanche Fuji, the corresponding tokens have been minted on Arbitrum Sepolia and sent to your receiver address.

Note: Since your Lock & Release token pool on Avalanche Fuji has locked some tokens, you can transfer tokens from Arbitrum Sepolia to Avalanche Fuji using CCIP as an exercise. Your tokens will be burned on Arbitrum Sepolia, and the corresponding tokens will be released on Avalanche Fuji. Make sure not to transfer more tokens than the amount of tokens locked in the token pool on Avalanche Fuji.