SauravKanchan / hashed-timelock-contract-ethereum

HTLC: Hashed Time Lock Contract

A Hashed Timelock Contract (HTLC) is a transactional agreement used in the cryptocurrency industry to produce conditional payments. It is basically a payment wherein the receiver or the beneficiary is required to acknowledge the receipt of payment before a predetermined time or a preset deadline. The receiver is required to acknowledge the payment in the form of cryptographic proof of payment, or else, they forfeit the ability to claim that payment. It is then refunded back to the payee.

Hence, an HTLC basically implements time-bound transactions in the crypto world. If the receiver does not generate a cryptographic proof of receipt of payment within a certain predetermined time frame, they will not receive any money, and the transaction becomes void.

To learn about HTLC read this article.

> htlc@1.0.0 test /home/saurav/projects/hashed-timelock-contract-ethereum
> hardhat test

Creating Typechain artifacts in directory typechain for target ethers-v5
Successfully generated Typechain artifacts!


  Hash Time Locked Contracts
    Contracts
      ✓ Should not be address(0)
      ✓ Should match total supply
    New HTLC
      ✓ Should approve amount
      ✓ Should create new contract (71ms)
    Withdraw
      ✓ Should be able withdraw with right conditions (44ms)

Pre Requisites

Before running any command, make sure to install dependencies:

$ npm i

Compile

Compile the smart contracts with Hardhat:

$ npm run compile

TypeChain

Compile the smart contracts and generate TypeChain artifacts:

$ npm run typechain

Lint Solidity

Lint the Solidity code:

$ npm run lint:sol

Lint TypeScript

Lint the TypeScript code:

$ npm run lint:ts

Test

Run the Chai tests:

$ npm run test

Coverage

Generate the code coverage report:

$ npm run coverage

Report Gas

See the gas usage per unit test and average gas per method call:

$ REPORT_GAS=true npm run test

Clean

Delete the smart contract artifacts, the coverage reports and the Hardhat cache:

$ npm run clean

Deploy

Deploy the contracts to Hardhat Network:

$ npm run deploy

Deploy the contracts to a specific network, such as the Ropsten testnet:

$ npm run deploy:network ropsten

Syntax Highlighting

If you use VSCode, you can enjoy syntax highlighting for your Solidity code via the vscode-solidity extension. The recommended approach to set the compiler version is to add the following fields to your VSCode user settings:

{
  "solidity.compileUsingRemoteVersion": "v0.8.3+commit.8d00100c",
  "solidity.defaultCompiler": "remote"
}

Where of course v0.8.3+commit.8d00100c can be replaced with any other version.