This Repo contains TestToken token smart contract based on ERC20.
ERC-20 is a standard interface for tokens.
The following standard allows for the implementation of a standard API for tokens within smart contracts.
More Information about Solidity Language and ERC-20 Standard:
The constructor function set the name, symbol, decimals and totalSupply of the token.
The view function balanceOf returns the account balance of account with address _owner.
The method transfer is called by an account and transfers _value amount of tokens to other address _to.
The method transferFrom allow one third account transfers _value amount of tokens from other address _from to other address _to.
Both methods fire the Transfer event.
The method increaseApproval allows other account _spender to withdraw from one account multiple times, up to the _addedValue amount.
The method decreaseApproval reduces the value aprroveed to _spender to withdraw from one account multiple times, substracting the _subtractedValue to the approval amount.
If the _subtractedValue is bigger than previously approved the value will reduce to 0.
The view function allowance returns the amount which address _spender is still allowed to withdraw from _owner.
Those methods are not a ERC-20 standard but are commonly used to create and destroy tokens.
The mintTo function creates _amount tokens and assigns them to account _to, increasing the total supply.
The burnFrom function destroys _amount tokens from account _from, reducing the total supply.
Only owner can mint or burn tokens in this case.
The Ownable module provides a basic access control mechanism, where there is an account (an owner) that can be granted exclusive access to specific functions.
This module is used through inheritance.
It will make available the modifier onlyOwner, which can be applied to your functions to restrict their use to the owner.
By default, the owner account will be the one that deploys the contract.
The owner address can be changed with method transferOwnership.
Contract module which allows children to implement an emergency stop mechanism that can be triggered by an authorized account.
This module is used through inheritance.
It will make available the modifiers whenNotPaused and whenPaused, which can be applied to the functions of your contract.
In this example, only owner account can trigger call pause and unpause methods.
You can compile, run tests and deploy this smart contract with Truffe.
Clone or donwload this repositorie.
Go to path and run on terminal:
npm installAfter running, all dependecies will be downloaded.
Maybe you need install truffle as global dependency to run next steps.
truffle compileAfter running, contract information — including ABI — will be available at the build/contracts/ directory.
truffle developtestOr, You can run tests which can be found in the test directory /test runing on terminal:
truffle testOr run tests within a specific file:
truffle test <file_path>Create .env file on root with:
PRIVATE_KEY = // Wallet private key
INFURA_PROJECT_ID = // Your Infura Project Id
TOKEN_NAME = "Token Name"
TOKEN_SYMBOL = "ERC"
TOKEN_DECIMALS = 18
TOKEN_TOTALSUPLY = 0
It is important that the chosen wallet has native tokens for the payment of gas.
Run migrate command:
truffle migrate --network <network_name> // mainnet, rinkeby, polygon, mumbai...After migration, contract address and transaction ID will be shown on screen.