fix: nft linker example (#165)

* chore: save temp work

* feat: fix and improve nft-linker example

* chore: cleanup example

* chore: update README.md

* chore: add nft-linker to the test

* chore: fix test

examples/evm/cross-chain-token/index.js

@@ -14,7 +14,7 @@ const name = 'An Awesome Axelar Cross Chain Token';
 const symbol = 'AACCT';
 const decimals = 13;
 
-async function deploy(chain, wallet) {
+async function deploy(chain, wallet, key) {
     console.log(`Deploying ERC20CrossChain for ${chain.name}.`);
     const provider = getDefaultProvider(chain.rpc);
     chain.wallet = wallet.connect(provider);
@@ -26,7 +26,7 @@ async function deploy(chain, wallet) {
         [chain.gateway, chain.gasService, decimals],
         [],
         defaultAbiCoder.encode(['string', 'string'], [name, symbol]),
-        'cross-chain-token',
+        key,
     );
     console.log(`Deployed ERC20CrossChain for ${chain.name} at ${chain.contract.address}.`);
 }

examples/evm/nft-linker/NftLinker.sol

@@ -30,12 +30,7 @@ contract NftLinker is ERC721, AxelarExecutable, Upgradable {
     }
 
     //The main function users will interract with.
-    function sendNFT(
-        address operator,
-        uint256 tokenId,
-        string memory destinationChain,
-        address destinationAddress
-    ) external payable {
+    function sendNFT(address operator, uint256 tokenId, string memory destinationChain, address destinationAddress) external payable {
         //If we are the operator then this is a minted token that lives remotely.
         if (operator == address(this)) {
             require(ownerOf(tokenId) == _msgSender(), 'NOT_YOUR_TOKEN');
@@ -47,12 +42,9 @@ contract NftLinker is ERC721, AxelarExecutable, Upgradable {
     }
 
     //Burns and sends a token.
-    function _sendMintedToken(
-        uint256 tokenId,
-        string memory destinationChain,
-        address destinationAddress
-    ) internal {
+    function _sendMintedToken(uint256 tokenId, string memory destinationChain, address destinationAddress) internal {
         _burn(tokenId);
+
         //Get the original information.
         (string memory originalChain, address operator, uint256 originalTokenId) = abi.decode(
             original[tokenId],
@@ -68,12 +60,7 @@ contract NftLinker is ERC721, AxelarExecutable, Upgradable {
     }
 
     //Locks and sends a token.
-    function _sendNativeToken(
-        address operator,
-        uint256 tokenId,
-        string memory destinationChain,
-        address destinationAddress
-    ) internal {
+    function _sendNativeToken(address operator, uint256 tokenId, string memory destinationChain, address destinationAddress) internal {
         //Create the payload.
         bytes memory payload = abi.encode(chainName, operator, tokenId, destinationAddress);
         string memory stringAddress = address(this).toString();
@@ -84,11 +71,7 @@ contract NftLinker is ERC721, AxelarExecutable, Upgradable {
     }
 
     //This is automatically executed by Axelar Microservices since gas was payed for.
-    function _execute(
-        string calldata, /*sourceChain*/
-        string calldata sourceAddress,
-        bytes calldata payload
-    ) internal override {
+    function _execute(string calldata /*sourceChain*/, string calldata sourceAddress, bytes calldata payload) internal override {
         //Check that the sender is another token linker.
         require(sourceAddress.toAddress() == address(this), 'NOT_A_LINKER');
         //Decode the payload.

examples/evm/nft-linker/README.md

@@ -17,9 +17,9 @@ To deploy the NFT Linker, run the following command:
 npm run deploy evm/nft-linker [local|testnet]
 ```
 
-The aforementioned command pertains to specifying the intended environment for a project to execute on. It provides the option to choose between local and testnet environments by appending either `local` or `testnet` after the command. 
+The aforementioned command pertains to specifying the intended environment for a project to execute on. It provides the option to choose between local and testnet environments by appending either `local` or `testnet` after the command.
 
-An example of its usage is demonstrated as follows: `npm run deploy evm/nft-linker local` or `npm run deploy evm/nft-linker testnet`. 
+An example of its usage is demonstrated as follows: `npm run deploy evm/nft-linker local` or `npm run deploy evm/nft-linker testnet`.
 
 A single NFT is minted to the deployer (`0xBa86A5719722B02a5D5e388999C25f3333c7A9fb`) on each chain.
 
@@ -35,7 +35,6 @@ npm run execute evm/nft-linker [local|testnet] ${srcChain} ${destChain}
 
 -   `srcChain` is `Avalanche`. Valid values are Moonbeam, Avalanche, Fantom, Ethereum, and Polygon
 -   `destChain` is `Fantom`. Valid values are Moonbeam, Avalanche, Fantom, Ethereum, and Polygon
--   `amount` is `10`
 
 **Note**:
 
@@ -53,16 +52,28 @@ npm run execute evm/nft-linker local "Avalanche" "Fantom"
 Output:
 
 ```
---- Initially ---
-Token that was originally minted at Moonbeam is at Moonbeam.
-Token that was originally minted at Avalanche is at Avalanche.
-Token that was originally minted at Fantom is at Fantom.
-Token that was originally minted at Ethereum is at Ethereum.
-Token that was originally minted at Polygon is at Polygon.
---- Then ---
-Token that was originally minted at Moonbeam is at Moonbeam.
-Token that was originally minted at Avalanche is at Polygon.
-Token that was originally minted at Fantom is at Fantom.
-Token that was originally minted at Ethereum is at Ethereum.
-Token that was originally minted at Polygon is at Polygon.
+==== Initially ====
+Minted token ID: '552232130' for Avalanche
+Token '552232130' was originally minted at Avalanche is at Avalanche.
+
+==== Approve Original NFT to NFTLinker's contract if needed ====
+Approved Original NFT (552232130) to NFTLinker's contract
+Tx Approved Hash: 0xb4f199d17785141f933f58e26d62b646461fd18ac878f4c62be10beea7aeab3d
+
+==== Send NFT to NFTLinker's contract ====
+Sent NFT 552232130 to NFTLinker's contract 0xa7df30a120c4a99f1843f5df6b5de7cc71fb55046cc25e7bdab5b60def1463ab
+Token ID at Fantom will be: '106441082702920043141391782483983459619906865214019059855714686922452481221015'
+
+==== Verify Result ====
+Token '106441082702920043141391782483983459619906865214019059855714686922452481221015' was originally minted at Avalanche is at Fantom.
+
+==== Approve Remote NFT to NFTLinker's contract ====
+Approved Remote NFT (106441082702920043141391782483983459619906865214019059855714686922452481221015) to NFTLinker's contract
+Tx Approved Hash: 0xc2d9c3628ffafea2df0e990bb103a5e2aa5d08ebc5e6f039dec21f17a6cf8699
+
+==== Send NFT back from 'Avalanche' to Fantom ====
+Sent NFT 106441082702920043141391782483983459619906865214019059855714686922452481221015 back to Avalanche 0x528bf12f90ac1468dd655624be544ef55c6948bc32bdeb373b7bdec8bec3ff5d
+
+==== Verify Result ====
+Token '552232130' was originally minted at Avalanche is at Avalanche.
 ```

examples/evm/nft-linker/index.js

@@ -1,7 +1,6 @@
 'use strict';
 
 const {
-    getDefaultProvider,
     utils: { keccak256, defaultAbiCoder },
 } = require('ethers');
 const {
@@ -13,97 +12,125 @@ const ERC721 = rootRequire('./artifacts/examples/evm/nft-linker/ERC721Demo.sol/E
 const ExampleProxy = rootRequire('./artifacts/examples/evm/Proxy.sol/ExampleProxy.json');
 const NftLinker = rootRequire('./artifacts/examples/evm/nft-linker/NftLinker.sol/NftLinker.json');
 
-const tokenId = 0;
+const tokenId = Math.floor(Math.random() * 1000000000);
 
-async function deploy(chain, wallet) {
-    console.log(`Deploying ERC721Demo for ${chain.name}.`);
+async function deploy(chain, wallet, key) {
     chain.erc721 = await deployContract(wallet, ERC721, ['Test', 'TEST']);
-    console.log(`Deployed ERC721Demo for ${chain.name} at ${chain.erc721.address}.`);
-    console.log(`Deploying NftLinker for ${chain.name}.`);
-    const provider = getDefaultProvider(chain.rpc);
-    chain.wallet = wallet.connect(provider);
+    console.log(`Deployed ERC721Demo for ${chain.name} at ${chain.erc721.address}`);
+
     chain.contract = await deployUpgradable(
         chain.constAddressDeployer,
-        wallet.connect(provider),
+        wallet,
         NftLinker,
         ExampleProxy,
         [chain.gateway, chain.gasService],
         [],
         defaultAbiCoder.encode(['string'], [chain.name]),
+        key,
     );
-    console.log(`Deployed NftLinker for ${chain.name} at ${chain.contract.address}.`);
-    console.log(`Minting token ${tokenId} for ${chain.name}`);
-    await (await chain.erc721.mint(tokenId)).wait();
-    console.log(`Minted token ${tokenId} for ${chain.name}`);
+    console.log(`Deployed NftLinker for ${chain.name} at ${chain.contract.address}`);
 }
 
 async function execute(chains, wallet, options) {
-    const { source: originChain, destination, calculateBridgeFee } = options;
+    const { source, destination, calculateBridgeFee } = options;
 
-    const ownerOf = async (chain = originChain) => {
-        const operator = chain.erc721;
-        const owner = await operator.ownerOf(tokenId);
+    const getOwnerDetails = async () => {
+        const sourceOwner = await source.erc721.ownerOf(tokenId);
 
-        if (owner !== chain.contract.address) {
-            return { chain: chain.name, address: owner, tokenId: BigInt(tokenId) };
+        if (sourceOwner !== source.contract.address) {
+            return {
+                chain: source.name,
+                ownerAddress: sourceOwner,
+                tokenId: BigInt(tokenId),
+            };
         }
 
         const newTokenId = BigInt(
-            keccak256(defaultAbiCoder.encode(['string', 'address', 'uint256'], [chain.name, operator.address, tokenId])),
+            keccak256(defaultAbiCoder.encode(['string', 'address', 'uint256'], [source.name, source.erc721.address, tokenId])),
         );
 
-        for (const checkingChain of chains) {
-            if (checkingChain === chain) continue;
+        const destOwner = destination.contract.ownerOf(newTokenId);
 
-            try {
-                const address = await checkingChain.contract.ownerOf(newTokenId);
-                return { chain: checkingChain.name, address, tokenId: newTokenId };
-            } catch (e) {}
+        if (destOwner) {
+            return { chain: destination.name, ownerAddress: destOwner, tokenId: newTokenId };
         }
 
-        return { chain: '' };
+        const ownerAddress = await source.erc721.ownerOf(tokenId);
+        return {
+            chain: source.name,
+            ownerAddress,
+            tokenId: BigInt(tokenId),
+        };
     };
 
-    async function print() {
-        for (const chain of chains) {
-            const owner = await ownerOf(chain);
-            console.log(`Token that was originally minted at ${chain.name} is at ${owner.chain}.`);
-        }
+    async function print(tokenId) {
+        const owner = await getOwnerDetails();
+        console.log(`Token '${tokenId}' was originally minted at ${source.name} is at ${owner.chain}.`);
     }
 
     const sleep = (ms) => new Promise((resolve) => setTimeout(resolve, ms));
 
-    const owner = await ownerOf();
-    const source = chains.find((chain) => chain.name === owner.chain);
-    if (source === destination) throw new Error('Token is already where it should be!');
+    console.log('==== Initially ====');
+    await source.erc721.mint(tokenId);
+    console.log(`Minted token ID: '${tokenId}' for ${source.name}`);
 
-    console.log('--- Initially ---');
-    await print();
+    await print(tokenId);
 
     const fee = await calculateBridgeFee(source, destination);
 
-    if (originChain === source) {
-        await (await source.erc721.approve(source.contract.address, owner.tokenId)).wait();
+    const owner = await getOwnerDetails();
+    const operatorAddress = source.erc721.address;
+
+    // Approve NFT to the NFTLinker contract
+    console.log(`\n==== Approve Original NFT to NFTLinker's contract if needed ====`);
+    const srcApproveTx = await source.erc721.approve(source.contract.address, owner.tokenId);
+    console.log(`Approved Original NFT (${tokenId}) to NFTLinker's contract`);
+    console.log(`Tx Approved Hash: ${srcApproveTx.hash}`);
+
+    // Send NFT to NFTLinker's contract
+    console.log("\n==== Send NFT to NFTLinker's contract ====");
+    const sendNftTx = await source.contract.sendNFT(operatorAddress, owner.tokenId, destination.name, wallet.address, { value: fee });
+    console.log(`Sent NFT ${tokenId} to NFTLinker's contract`, sendNftTx.hash);
+
+    const destinationTokenId = BigInt(
+        keccak256(defaultAbiCoder.encode(['string', 'address', 'uint256'], [source.name, operatorAddress, tokenId])),
+    );
+    console.log(`Token ID at ${destination.name} will be: '${destinationTokenId}'`);
+
+    while (true) {
+        const originalDetails = await destination.contract.original(destinationTokenId);
+        if (originalDetails !== '0x') break;
+        await sleep(2000);
     }
 
-    await (
-        await source.contract.sendNFT(
-            originChain === source ? source.erc721.address : source.contract.address,
-            owner.tokenId,
-            destination.name,
-            wallet.address,
-            { value: fee },
-        )
-    ).wait();
+    console.log('\n==== Verify Result ====');
+    await print(destinationTokenId);
+
+    console.log("\n==== Approve Remote NFT to NFTLinker's contract ====");
+    const destApproveTx = await destination.contract.approve(destination.contract.address, destinationTokenId);
+    console.log(`Approved Remote NFT (${destinationTokenId}) to NFTLinker's contract`);
+    console.log(`Tx Approved Hash: ${destApproveTx.hash}`);
+
+    console.log(`\n==== Send NFT back from '${source.name}' to ${destination.name} ====`);
+    const sendBackNftTx = await destination.contract.sendNFT(
+        destination.contract.address,
+        destinationTokenId,
+        source.name,
+        wallet.address,
+        {
+            value: fee,
+        },
+    );
+    console.log(`Sent NFT ${destinationTokenId} back to ${source.name}`, sendBackNftTx.hash);
 
     while (true) {
-        const owner = await ownerOf();
-        if (owner.chain === destination.name) break;
+        const owner = await source.erc721.ownerOf(tokenId);
+        if (owner === wallet.address) break;
         await sleep(2000);
     }
 
-    console.log('--- Then ---');
-    await print();
+    console.log('\n==== Verify Result ====');
+    await print(tokenId);
 }
 
 module.exports = {

examples/tests/evm.test.js

@@ -22,6 +22,7 @@ const examples = [
     'cross-chain-token',
     'deposit-address',
     'nonced-execution',
+    'nft-linker',
     'send-ack',
     'send-token',
 ];

scripts/libs/deploy.js

@@ -62,9 +62,10 @@ async function deployOnAltChain(example) {
 
 // Deploy the contracts.
 function deployOnEvmChain(chains, wallet, example) {
+    const key = new Date().getTime().toString();
     const deploys = chains.map((chain) => {
         const provider = getDefaultProvider(chain.rpc);
-        return example.deploy(chain, wallet.connect(provider));
+        return example.deploy(chain, wallet.connect(provider), key);
     });
 
     return Promise.all(deploys);

scripts/libs/utils.js

@@ -166,7 +166,7 @@ async function calculateBridgeExpressFee(source, destination, options = {}) {
         },
     );
 
-    const expressMultiplier = response.apiResponse.result.express_execute_gas_adjustment_with_multiplier;
+    const expressMultiplier = response.apiResponse.result.express_execute_gas_multiplier;
     const floatToIntFactor = 10000;
 
     // baseFee + executionFeeWithMultiplier + expressFee