Contract

Sardis use EVM for contract execution.See Solidity for detail.

Remix

Remix IDE is an open source web and desktop application. It fosters a fast development cycle and has a rich set of plugins with intuitive GUIs. Remix is used for the entire journey of contract development as well as being a playground for learning and teaching contract development.

Create new file in file explorer. Edit contract info at right side.

Compile contract

1. Click compiler button, switch UI
2. Select contract you want to compile
3. Set compile flags
4. Clieck compile button

Deploy contract to blockchain via wallet such as MetaMask.

1. Set network info in Metamask.

2. Back to Remix.

• Swich environment
• Select contract
• click deploy button

And then by MetaMask the contract deployemnt transaction can be broadcast to the Sardis Network.

Truffle

Use truffle to compile and deploy contract.

• Install Node.js See Installing Node.js for detail.

• Install truffle

npm install -g truffle

Run truffle version after installation finished. If the command line displays a message like below, installation is successful.

Truffle v5.1.36 (core: 5.1.36)
Solidity v0.5.16 (solc-js)
Node v10.22.1
Web3.js v1.2.1

• Create project

First,create folder for project.

mkdir Example
cd Example

Then, init project via truffle

truffle init

After initialization is complete, the following file structure is generated within the project.

|-- contracts         //folder for contracts
|-- migrations        //folder for deployment scripts
|-- test              //folder for test scripts
|-- truffle-config.js //truffle config file

• Config truffle info

const HDWalletProvider = require('@truffle/hdwallet-provider');

const fs = require('fs');
const mnemonic = fs.readFileSync(".secret").toString().trim();

module.exports = {
  networks: {
    testnet: {
      provider: () => new HDWalletProvider(mnemonic, 'https://contract-testnet.sardisnetwork.com'),
      network_id: 256
    },
    mainnet: {
      provider: () => new HDWalletProvider(mnemonic, 'https://http-mainnet.sardisnetwork.com'),
      network_id: 128
    }
  },

  // Set default mocha options here, use special reporters etc.
  mocha: {
    // timeout: 100000
  },

  // Configure your compilers
  compilers: {
    solc: {
      // version: "0.5.1",    // 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"
      // }
    },
  },
};

• Create contract Put custom contracts into folder contracts and modify deployment script in folder migrations.

• Deploy contract

Run the deployment command.

truffle migrate --network testnet

The output as below.

2_example_migration.js
======================

   Deploying 'ExampleToken'
   ------------------------
   > transaction hash:    0x91e50594a63bc6f4c299f3f445868571678be306b835bddce6dff5c7a5ddf9dc
   > Blocks: 2            Seconds: 4
   > contract address:    0x54D2049715FC8De1361D7350de90eb05F0f6CA84
   > block number:        375304
   > block timestamp:     1608016637
   > account:             0x03D32B774295D740ffEe43b20fcC0a53acC576e6
   > balance:             878.909609236165318643
   > gas used:            1056044 (0x101d2c)
   > gas price:           20 gwei
   > value sent:          0 ETH
   > total cost:          0.02112088 ETH


   > Saving migration to chain.
   > Saving artifacts
   -------------------------------------
   > Total cost:          0.02112088 ETH


Summary
=======
> Total deployments:   1
> Final cost:          0.02112088 ETH

Finally, the contract deployment is complete.