# Truffle: Deploying a Smart Contract
Learn how to deploy a simple Solidity-based smart contract to Plug Chain using the Truffle environment
# Pre-requisite Readings
Truffle (opens new window) is a development framework for deploying and managing Solidity (opens new window) smart contracts.
# Install Dependencies
First, install the latest Truffle version on your machine globally.
yarn install truffle -g
tip If you haven't already, you will also need to install Plug Chain if you plan on deploying your smart contracts locally. Check this document for the full instructions.
# Create Truffle Project
In this step we will create a simple counter contract. Feel free to skip this step if you already have your own compiled contract.
Create a new directory to host the contracts and initialize it:
mkdir plugchain-truffle
cd plugchain-truffle
Initialize the Truffle suite with:
truffle init
Create contracts/Counter.sol
containing the following contract:
pragma solidity >=0.7.0 <0.9.0;
contract Counter {
uint256 counter = 0;
function add() public {
counter++;
}
function subtract() public {
counter--;
}
function getCounter() public view returns (uint256) {
return counter;
}
}
Compile the contract using the compile
command:
truffle compile
Create test/counter_test.js
containing the following tests in Javascript using Mocha (opens new window):
const Counter = artifacts.require("Counter")
contract('Counter', accounts => {
const from = accounts[0]
let counter
before(async() => {
counter = await Counter.new()
})
it('should add', async() => {
await counter.add()
let count = await counter.getCounter()
assert(count == 1, `count was ${count}`)
})
})
# Truffle configuration
Open truffle-config.js
and uncomment the development
section in networks
:
development: {
host: "127.0.0.1", // Localhost (default: none)
port: 8545, // Standard Ethereum port (default: none)
network_id: "*", // Any network (default: none)
},
This will allow your contract to connect to your Plug Chain local node.
# Start Node
Start your local node using the following command on the Terminal
# from the ~/.plugchain/ directory
$ init.sh
tip For further information on how to run a node, please refer to the quickstart guide.
# Deploy contract
In the Truffle terminal, migrate the contract using:
truffle migrate --network development
You should see incoming deployment logs in the Plug Chain daemon Terminal tab for each transaction (one to deploy Migrations.sol
and the other to deploy Counter.sol
).
$ I[2020-07-15|17:35:59.934] Added good transaction module=mempool tx=22245B935689918D332F58E82690F02073F0453D54D5944B6D64AAF1F21974E2 res="&{CheckTx:log:\"[]\" gas_wanted:6721975 }" height=3 total=1
I[2020-07-15|17:36:02.065] Executed block module=state height=4 validTxs=1 invalidTxs=0
I[2020-07-15|17:36:02.068] Committed state module=state height=4 txs=1 appHash=76BA85365F10A59FE24ADCA87544191C2D72B9FB5630466C5B71E878F9C0A111
I[2020-07-15|17:36:02.981] Added good transaction module=mempool tx=84516B4588CBB21E6D562A6A295F1F8876076A0CFF2EF1B0EC670AD8D8BB5425 res="&{CheckTx:log:\"[]\" gas_wanted:6721975 }" height=4 total=1
# Run Truffle tests
Now, you can run the Truffle tests using the Plug Chain node using the test
command:
$ truffle test --network development
Using network 'development'.
Compiling your contracts...
===========================
> Everything is up to date, there is nothing to compile.
Contract: Counter
✓ should add (5036ms)
1 passing (10s)