tenderly.md

🔍 Tenderly

Tenderly is a platform for monitoring, alerting and trouble-shooting smart contracts. They also have a hardhat plugin and CLI tool that can be helpful for local development!

{% hint style="info" %} Hardhat Tenderly announcement blog for reference. {% endhint %}

Verifying contracts on Tenderly

Scaffold-eth includes the hardhat-tenderly plugin. When deploying to any of the following networks:

• kovan
• goerli
• mainnet
• rinkeby
• ropsten
• matic
• mumbai
• xDai
• POA

You can verify contracts as part of a deployment script like so:

let verification = await tenderly.verify({
  name: contractName,
  address: contractAddress,
  network: targetNetwork,
});

Once verified, they will then be available to view on Tenderly!

Exporting local Transactions

One of Tenderly's best features for builders is the ability to upload local transactions so that you can use all of Tenderly's tools for analysis and debugging. You will need to create a tenderly account if you haven't already.

Exporting local transactions can be done using the Tenderly CLI. Installing the Tenderly CLI:

brew tap tenderly/tenderly
brew install tenderly

{% hint style="info" %} See alternative installation steps here {% endhint %}

You need to log in and configure for your local chain (including any forking information) - this can be done from any directory, but it probably makes sense to do under /packages/hardhat to ensure that local contracts are also uploaded with the local transaction (see more below!)

cd packages/hardhat
tenderly login
tenderly export init

You can then take transaction hashes from your local chain and run the following from the packages/hardhat directory:

tenderly export <transactionHash>

Which will upload them to tenderly.co/dashboard!

Tenderly also allows users to debug smart contracts deployed to a local fork of some network (see yarn fork). To let Tenderly know that we are dealing with a fork, run the following command:

tenderly export init

CLI will ask you for your network's name and whether you are forking a public network. After choosing the right fork, your exporting will look something like this:

tenderly export <transactionHash> --export-network <networkName>

Note that tenderly.yaml file stores information about all networks that you initialized for exporting transactions. There can be multiple of them in a single file. You only need the --export-network if you have more than one network in your tenderly.yaml config!

A quick note on local contracts

If your local contracts are persisted in a place that Tenderly can find them, then they will also be uploaded as part of the local transaction export, which is one of the freshest features! We are using hardhat-deploy, which stores the contracts & meta-information in a deployments folder, so this should work out of the box.

Another pitfall when dealing with a local network (fork or not) is that you will not see the transaction hash if it fails. This happens because the hardhat detects an error while eth_estimateGas is executed. To prevent such behaviour, you can skip this estimation by passing a gasLimit override when making a call - an example of this is demonstrated in the FunctionForm.jsx file of the Contract component:

let overrides = {}
// Uncomment the next line if you want to skip the gas estimation for each transaction
// overrides.gasLimit = hexlify(1200000);
const returned = await tx(contractFunction(...args, overrides));

One gotcha - Tenderly does not (currently) support yarn workspaces, so any imported solidity contracts need to be local to packages/hardhat for your contracts to be exported. You can achieve this by using nohoist - this has been done for hardhat so that we can export console.sol - see the top-level package.json to see how!

"workspaces": {
  "packages": [
    "packages/*"
  ],
  "nohoist": [
    "**/hardhat",
    "**/hardhat/**"
  ]
}