Using Truffle for Deploying Smart Contracts on BSC
In this tutorial, you will learn to create, compile and deploy smart contract on the BNB Smart Chain network using the Truffle IDE.
Setting up the development environment
Requirements
There are a few technical requirements before we start. Please install the following:
- Windows, Linux or Mac OS X
- Node.js v8.9.4 LTS or later
- Git
Recommendations for Windows If you're running Truffle on Windows, you may encounter some naming conflicts that could prevent Truffle from executing properly. Please refer to the official Truffle Documentation to find solutions for resolving naming conflicts.
Installing Truffle
Once the above mentioned softwares are installed, we only need one command to install Truffle:
npm install -g truffle
To verify that Truffle is installed properly, type truffle version
on a terminal. If you see an error, make sure that your npm modules are added to your path.
If you're new to Truffle then please follow the Getting Started by truffle, To setup the truffle environment.
Project Creation, Compilation, and Configuration
To use most Truffle commands, you need to run them against an existing Truffle project. So the first step is to create a Truffle project.
Creation
For creating a scaffold project for getting started, you can use the Truffle Boxes, BSC Starter Box which is a boilerplate to jump start development on the BNB Smart Chain.
For this tutorial, we have used the MetaCoin box as an example, which creates a token that can be transferred between accounts. Use the command truffle unbox metacoin
to unbox the metacoin box.
NOTE: You can use the
truffle unbox <box-name>
command to download any of the other Truffle Boxes. Another alternative is to create a bare Truffle project with no smart contracts included using thetruffle init
command.
Once this operation is completed, you'll now have a project structure with the following items:
- contracts/: Directory for Solidity contracts
- migrations/: Directory for scriptable deployment files
- test/: Directory for test files for testing your application and contracts
- truffle-config.js: Truffle configuration file
Create Contract
You can write your own smart contract or download the BEP20 token smart contract template and place it in the contracts
directory.
Compile Contract
To compile a Truffle project, change to the root of the directory where the project is located and then type the following into a terminal:
truffle compile
Configuring Truffle for BSC
- Go to truffle-config.js
- Update the truffle-config with bsc-network-crendentials.
const HDWalletProvider = require('@truffle/hdwallet-provider');
const fs = require('fs');
const mnemonic = fs.readFileSync(".secret").toString().trim();
module.exports = {
networks: {
development: {
host: "127.0.0.1", // Localhost (default: none)
port: 8545, // Standard BSC port (default: none)
network_id: "*", // Any network (default: none)
},
testnet: {
provider: () => new HDWalletProvider(mnemonic, `https://data-seed-prebsc-1-s1.binance.org:8545`),
network_id: 97,
confirmations: 10,
timeoutBlocks: 200,
skipDryRun: true
},
bsc: {
provider: () => new HDWalletProvider(mnemonic, `https://bsc-dataseed1.binance.org`),
network_id: 56,
confirmations: 10,
timeoutBlocks: 200,
skipDryRun: true
},
},
// Set default mocha options here, use special reporters etc.
mocha: {
// timeout: 100000
},
// Configure your compilers
compilers: {
solc: {
version: "^0.8.0", // A version or constraint - Ex. "^0.5.0"
}
}
}
NOTE: Notice, it requires mnemonic to be passed in for Provider, this is the seed phrase for the account you'd like to deploy from. Create a new .secret file in root directory and enter your 12 word mnemonic seed phrase to get started. To get the seedwords from metamask wallet you can go to Metamask Settings, then from the menu choose Security and Privacy where you will see a button that says reveal seed words, refer here for more details.
Deploying on BSC Network
Run this command in root of the project directory:
$ truffle migrate --network testnet
Contract will be deployed on Binance Chain Chapel Testnet, it look like this:
1_initial_migration.js
======================
Deploying 'Migrations'
----------------------
> transaction hash: 0xaf4502198400bde2148eb4274b08d727a17080b685cd2dcd4aee13d8eb954adc
> Blocks: 3 Seconds: 9
> contract address: 0x81eCD10b61978D9160428943a0c0Fb31a5460466
> block number: 3223948
> block timestamp: 1604049862
> account: 0x623ac9f6E62A8134bBD5Dc96D9B8b29b4B60e45F
> balance: 6.24574114
> gas used: 191943 (0x2edc7)
> gas price: 20 gwei
> value sent: 0 ETH
> total cost: 0.00383886 ETH
Pausing for 5 confirmations...
------------------------------
> confirmation number: 2 (block: 3223952)
> confirmation number: 3 (block: 3223953)
> confirmation number: 4 (block: 3223954)
> confirmation number: 6 (block: 3223956)
> Saving migration to chain.
> Saving artifacts
-------------------------------------
> Total cost: 0.00383886 ETH
Summary
=======
> Total deployments: 1
> Final cost: 0.00383886 ETH
Note Remember your address, transaction_hash and other details provided would differ, Above is just to provide an idea of structure.
🎉 Congratulations! You have successfully deployed BEP20 Smart Contract. Now you can interact with the Smart Contract.
You can check the deployment status here: https://bscscan.com/ or https://testnet.bscscan.com/
Verify Your Contract on BscScan
The recommended way to verify a smart contract is using the plugin. It is easier to read and imports and licenses are maintained.
Verified using Truffle
Example: https://testnet.bscscan.com/token/0x68D2E27940CA48109Fa3DaD0D2C8B27E64a0c6cf
GitHub Project: https://github.com/huangsuyu/verify-example
BscScan plugin for Truffle
Truffle has a BscScan plugin: truffle-plugin-verify
You need to deploy with Truffle to verify with the Truffle verify plugin.
Get API key: https://bscscan.com/myapikey
Install the plugin
npm install -D truffle-plugin-verify
Configure the plugin
Configure the plugin in truffle-config.js
using the following command
const HDWalletProvider = require("@truffle/hdwallet-provider");
// const infuraKey = "fj4jll3k.....";
//
const { mnemonic, BSCSCANAPIKEY} = require('./env.json');
module.exports = {
plugins: [
'truffle-plugin-verify'
],
api_keys: {
bscscan: BSCSCANAPIKEY
},
networks: {
testnet: {
provider: () => new HDWalletProvider(mnemonic, `https://data-seed-prebsc-1-s1.binance.org:8545`),
network_id: 97,
timeoutBlocks: 200,
confirmations: 5,
production: true // Treats this network as if it was a public net. (default: false)
}
},
// Set default mocha options here, use special reporters etc.
mocha: {
timeout: 100000
},
// Configure your compilers
compilers: {
solc: {
version: "0.5.16", // Fetch exact version from solc-bin (default: truffle's version)
// docker: true, // Use "0.5.1" you've installed locally with docker (default: false)
settings: { // See the solidity docs for advice about optimization and evmVersion
optimizer: {
enabled: false,
runs: 200
},
evmVersion: "byzantium"
}
},
},
};
Verification Command
truffle run verify BEP20Token@{contract-address} --network testnet
You should see the following output:
Verifying BEP20Token@0x68D2E27940CA48109Fa3DaD0D2C8B27E64a0c6cf
Pass - Verified: https://testnet.bscscan.com/address/0x68D2E27940CA48109Fa3DaD0D2C8B27E64a0c6cf#contracts
Successfully verified 1 contract(s).