5. Using Truffle

Use Truffle to quickly build a dApp on ChainIDE

Consensys Announces the Sunset of Truffle and Ganache and New HardHat Partnership, more details.

1. Open Sandbox

Note: Sandbox functionality is only available after logging in to ChainIDE via GitHub.

Open Sandbox

2. Create a project

You need to run most Truffle commands against an existing Truffle project. So the first step is to create a Truffle project.

You can create a bare project without smart contracts using truffle init, but for those getting started, you can use Truffle Boxes, which are example applications and project templates. We'll use the MetaCoin box, which creates a token that can be transferred between accounts. Note that this is not ERC-20 compatible.

1. Download ("unbox") the MetaCoin box:

truffle unbox metacoin [PATH/TO/DIRECTORY]

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.js: Truffle configuration file

3. Explore the project

1. Open the contracts/MetaCoin.sol file in a text editor. This is a smart contract (written in Solidity) that creates a MetaCoin token. Note that this also references another Solidity file contracts/ConvertLib.sol in the same directory.

2. Open the migrations/1_deploy_contracts.js file. This file is the migration (deployment) script.

3. Open the test/TestMetaCoin.sol file. This is a test file written in Solidity which ensures that your contract is working as expected.
4. Open the test/metacoin.js file. This is a test file written in JavaScript which performs a similar function to the Solidity test above. The box does not include one, but Truffle tests can also be written in typescript.
5. Open the truffle-config.js file. This is the Truffle configuration file, for setting network information and other project-related settings. The file is blank, but this is okay, as we'll be using a Truffle command that has some defaults built-in.

4. Test

To run all tests, you can simply run truffle test. Because development is commented out in truffle-config.js, truffle test will spin up and tear down a local test instance (ganache). If you want to use more of ganache's features, you can spin up a separate instance and specify the port number in the truffle-config.

TestMetaCoin
  ✔ testInitialBalanceUsingDeployedContract
  ✔ testInitialBalanceWithNewMetaCoin

Contract: MetaCoin
  ✔ should put 10000 MetaCoin in the first account
  ✔ should call a function that depends on a linked library
  ✔ should send coin correctly (52ms)

You can also run each test individually by calling truffle test ./test/TestMetaCoin.sol and truffle test ./test/metacoin.js.

5. Compile

If you want to only compile, you can simply run truffle compile.

You will see the following output:

Compiling your contracts...
===========================
> Compiling ./contracts/ConvertLib.sol
> Compiling ./contracts/MetaCoin.sol
> Artifacts written to /Users/emilylin/dev/metacoin-box/build/contracts
> Compiled successfully using:
- solc: 0.8.13+commit.abaa5c0e.Emscripten.clang

6. Migrate with Truffle Develop

To deploy our smart contracts, we're going to need to connect to a blockchain. Truffle has a built-in personal blockchain that can be used for testing. This blockchain is local to your system and does not interact with the main Ethereum network.

1. Run Truffle Develop:

truffle develop

You will see the following information:

Truffle Develop started at http://127.0.0.1:9545/

Accounts:
(0) 0x627306090abab3a6e1400e9345bc60c78a8bef57
(1) 0xf17f52151ebef6c7334fad080c5704d77216b732
(2) 0xc5fdf4076b8f3a5357c5e395ab970b5b54098fef
(3) 0x821aea9a577a9b44299b9c15c88cf3087f3b5544
(4) 0x0d1d4e623d10f9fba5db95830f7d3839406c6af2
(5) 0x2932b7a2355d6fecc4b5c0b6bd44cc31df247a2e
(6) 0x2191ef87e392377ec08e7c08eb105ef5448eced5
(7) 0x0f4f2ac550a1b4e2280d04c21cea7ebd822934b5
(8) 0x6330a553fc93768f612722bb8c2ec78ac90b3bbc
(9) 0x5aeda56215b167893e80b4fe645ba6d5bab767de

Private Keys:
(0) c87509a1c067bbde78beb793e6fa76530b6382a4c0241e5e4a9ec0a0f44dc0d3
(1) ae6ae8e5ccbfb04590405997ee2d52d2b330726137b875053c36d94e974d162f
(2) 0dbbe8e4ae425a6d2687f1a7e3ba17bc98c673636790f1b8ad91193c05875ef1
(3) c88b703fb08cbea894b6aeff5a544fb92e78a18e19814cd85da83b71f772aa6c
(4) 388c684f0ba1ef5017716adb5d21a053ea8e90277d0868337519f97bede61418
(5) 659cbb0e2411a44db63778987b1e22153c086a95eb6b18bdf89de078917abc63
(6) 82d052c865f5763aad42add438569276c00d3d88a2d062d36b2bae914d58b8c8
(7) aa3680d5d48a8283413f7a108367c7299ca73f553735860a87b08f39395618b7
(8) 0f62d96d6675f32685bbdb8ac13cda7c23436f63efbb9d07700d8669ff12b7c4
(9) 8d5366123cb560bb606379f90a0bfd4769eecc0557f1b362dcae9012b548b1e5

Mnemonic: candy maple cake sugar pudding cream honey rich smooth crumble sweet treat

⚠️  Important ⚠️  : This mnemonic was created for you by Truffle. It is not secure.
Ensure you do not use it on production blockchains, or else you risk losing funds.

truffle(development)>

This shows ten accounts (and their private keys) that can be used when interacting with the blockchain.

1. On the Truffle Develop prompt, Truffle commands can be run by omitting the truffle prefix. For example, to run truffle compile on the prompt, type compile. The command to deploy your compiled contracts to the blockchain is truffle migrate. By default, truffle migrate will also run truffle compile, so you can just do the following:

migrate

You will see the following output:

Starting migrations...
======================
> Network name:    'develop'
> Network id:      4447
> Block gas limit: 6721975

1_initial_migration.js
======================

   Deploying 'Migrations'
   ----------------------
   > transaction hash:    0x3fd222279dad48583a3320decd0a2d12e82e728ba9a0f19bdaaff98c72a030a2
   > Blocks: 0            Seconds: 0
   > contract address:    0xa0AdaB6E829C818d50c75F17CFCc2e15bfd55a63
   > account:             0x627306090abab3a6e1400e9345bc60c78a8bef57
   > balance:             99.99445076
   > gas used:            277462
   > gas price:           20 gwei
   > value sent:          0 ETH
   > total cost:          0.00554924 ETH

   > Saving migration to chain.
   > Saving artifacts
   -------------------------------------
   > Total cost:          0.00554924 ETH

2_deploy_contracts.js
=====================

   Deploying 'ConvertLib'
   ----------------------
   > transaction hash:    0x97e8168f1c05fc40dd8ffc529b9a2bf45cc7c55b07b6b9a5a22173235ee247b6
   > Blocks: 0            Seconds: 0
   > contract address:    0xfb39FeaeF3ac3fd46e2123768e559BCe6bD638d6
   > account:             0x627306090abab3a6e1400e9345bc60c78a8bef57
   > balance:             99.9914458
   > gas used:            108240
   > gas price:           20 gwei
   > value sent:          0 ETH
   > total cost:          0.0021648 ETH

   Linking
   -------
   * Contract: MetaCoin <--> Library: ConvertLib (at address: 0xfb39FeaeF3ac3fd46e2123768e559BCe6bD638d6)

   Deploying 'MetaCoin'
   --------------------
   > transaction hash:    0xee4994097c10e7314cc83adf899d67f51f22e08b920e95b6d3f75c5eb498bde4
   > Blocks: 0            Seconds: 0
   > contract address:    0x6891Ac4E2EF3dA9bc88C96fEDbC9eA4d6D88F768
   > account:             0x627306090abab3a6e1400e9345bc60c78a8bef57
   > balance:             99.98449716
   > gas used:            347432
   > gas price:           20 gwei
   > value sent:          0 ETH
   > total cost:          0.00694864 ETH

   > Saving migration to chain.
   > Saving artifacts
   -------------------------------------
   > Total cost:          0.00911344 ETH

Summary
=======
> Total deployments:   3
> Final cost:          0.01466268 ETH

This shows the transaction IDs and addresses of your deployed contracts. It also includes a cost summary and real-time status updates.

Note: Your transaction hashes, contract addresses, and accounts will be different from the above.

Note: To see how to interact with the contract, please skip to the next section.

7. Migrate with Truffle Console

While Truffle Develop is an all-in-one personal blockchain and console, it spins up a very basic instance of ganache. You can also use a desktop application, to launch your personal blockchain, which is an easier to understand tool for those new to Ethereum and the blockchain, as it displays much more information up-front. Alternatively, if you want to customize your ganache instance using all the options available to you through ganache v7.

The only extra step, aside from running Ganache, is that it requires editing the Truffle configuration file to point to the Ganache instance.

1. Open truffle-config.js in a text editor. Replace the content with the following, ensuring your port number is correct:

module.exports = {
  networks: {
    development: {
      host: "*******",   // Remove 'https:' from the local link generated by the previous port forwarding****//”
      port: 80,          // The port 80 is used for HTTP
      network_id: "*"
    }
  }
};

This will allow a connection using Ganache's default connection parameters.

1. Save and close that file.

2. On the terminal, migrate the contract to the blockchain created by Ganache:

truffle migrate

You will see the following output:

Compiling your contracts...
===========================
> Everything is up to date, there is nothing to compile.


Starting migrations...
======================
> Network name:    'development'
> Network id:      1661545227029
> Block gas limit: 30000000 (0x1c9c380)


1_deploy_contracts.js
=====================

Deploying 'ConvertLib'
----------------------
> transaction hash:    0x259332521763056a5b949d33e3f52bff424c357b56af939ca46f96baa4386729
> Blocks: 0            Seconds: 0
> contract address:    0x7c31fB61DC4b817A7AFF135382FC85bcc9078f5e
> block number:        1
> block timestamp:     1661545283
> account:             0x0BD3Ea7C1CDE97e91e83615D7F6eF8910b3d0FEB
> balance:             999.999468208
> gas used:            157568 (0x26780)
> gas price:           3.375 gwei
> value sent:          0 ETH
> total cost:          0.000531792 ETH


Linking
-------
* Contract: MetaCoin <--> Library: ConvertLib (at address: 0x7c31fB61DC4b817A7AFF135382FC85bcc9078f5e)

Deploying 'MetaCoin'
--------------------
> transaction hash:    0x86b381fa96891e619a60a75db681d8aa95648b53572acc02690c9b94c76eadae
> Blocks: 0            Seconds: 0
> contract address:    0x03709DE4e1a3dA52505345Bd5129b48Ac891d63B
> block number:        2
> block timestamp:     1661545283
> account:             0x0BD3Ea7C1CDE97e91e83615D7F6eF8910b3d0FEB
> balance:             999.998107289579739204
> gas used:            416594 (0x65b52)
> gas price:           3.266773934 gwei
> value sent:          0 ETH
> total cost:          0.001360918420260796 ETH

> Saving artifacts
-------------------------------------
> Total cost:     0.001892710420260796 ETH

Summary
=======
> Total deployments:   2
> Final cost:          0.001892710420260796 ETH

This shows the transaction IDs and addresses of your deployed contracts. It also includes a cost summary and real-time status updates.

Note: Your transaction IDs and contract addresses may be different from the above.

1. To interact with the contract, you can use the Truffle console. The Truffle console is similar to Truffle Develop, except it connects to an existing blockchain (in this case, the one generated by Ganache).

truffle console

You will see the following prompt:

truffle(development)>

8. Interact with the contract

Interact with the contract using the console in the following ways:

We're using web3.eth.getAccounts() in these examples, which returns a promise which resolves to an array of all the accounts generated by the mnemonic. So, given the addresses generated by our mnemonic above, specifying (await web3.eth.getAccounts())[0] is equivalent to the address 0x627306090abab3a6e1400e9345bc60c78a8bef57.

As of Truffle v5, the console supports async/await functions, enabling much simpler interactions with the contract.

• Begin by establishing both the deployed MetaCoin contract instance and the accounts created by either Truffle's built-in blockchain or Ganache:

truffle(development)> let instance = await MetaCoin.deployed()
truffle(development)> let accounts = await web3.eth.getAccounts()

• Check the metacoin balance of the account that deployed the contract:

truffle(development)> let balance = await instance.getBalance(accounts[0])
truffle(development)> balance.toNumber()

• See how much ether that balance is worth (and note that the contract defines a metacoin to be worth 2 ether):

truffle(development)> let ether = await instance.getBalanceInEth(accounts[0])
truffle(development)> ether.toNumber()

• Transfer some metacoin from one account to another:

truffle(development)> instance.sendCoin(accounts[1], 500)

• Check the balance of the account that received the metacoin:

truffle(development)> let received = await instance.getBalance(accounts[1])
truffle(development)> received.toNumber()

• Check the balance of the account that sent the metacoin:

truffle(development)> let newBalance = await instance.getBalance(accounts[0])
truffle(development)> newBalance.toNumber()

9. Deploy to Mainnet, Testnet, and Beyond

If you want to deploy to alternative networks, consider using Truffle Dashboard. Just call truffle dashboard and deploy, test, and run the console using --network dashboard.

10. Continue learning

This quickstart showed you the basics of the Truffle project lifecycle, but there is much more to learn. Please continue on with the rest of truffle documentation, Arbitrum Box and check out truffle unleashed series for the latest tutorials and interviews with industry experts!