TRON Developer Guide — Smart Contract Deployment

Example Tutorial Project

The MetaCoin TronBox example tutorial project can be found here.

Smart Contract Development

The ./contracts directory contains all your contracts. By default, there is a contract file and a library file within the .sol extension. Even though the library file has some unique properties, for simplicity purposes, it will be referred to as a contract.

Tronbox requires the contract name and file name to be defined the same. For example, if the file name is Test.sol, we can write the contract as follows:

• Solidity

pragma solidity ^0.4.23;
contract Test{
    function f() returns (string){
        return "method f()";
    }
    function g() returns (string){
        return "method g()";
    }
}

This type of contract is case-sensitive. The recommendation is to capitalize each opening letter, as shown in the above code.

Increase Deploy Configuration

Configuring migrations/2_deploy_contracts.js as follows:

• 2_deploy_contracts.js

var Migrations = artifacts.require("./Migrations.sol");
var Test = artifacts.require("./Test.sol");
module.exports = function(deployer) {
  deployer.deploy(Migrations);
  deployer.deploy(Test);
};

The above code has two extra lines. One line is var Test = artifacts.require("./Test.sol"), which declares a new contract instance as Test; This increases a new line deployer.deploy(Test); Use Test for deployment.

Configuration

The tronbox.js file holds configurations the contract will deploy to. To specify the network, use — network NETWORK_NAME when migrating or testing.

• tronbox.js

module.exports = {
  networks: {
      development: {
from: 'some address',
          privateKey: 'some private key',
          consume_user_resource_percent: 30,
          fee_limit: 100000000,
          fullNode: "https://api.trongrid.io",
          solidityNode: "https://api.trongrid.io",
          eventServer:  "it is optional",
          network_id: "*" // Match any network id
      },
      production: {
          from: 'some other address',
          privateKey: 'some other private key',
          consume_user_resource_percent: 30,
          fee_limit: 100000000,
          fullNode: "https://api.trongrid.io",
          solidityNode: "https://api.trongrid.io",
          eventServer:  "it is optional",
          network_id: "*" // Match any network id
      },
    ..... you can define other network configuration as well
  }
};

Compiler Configuration

In tronbox.js, you can add the option useZeroFourCompiler: true to force TronBox to compile the contract as if the connected full node hosts a version of JavaTron lower than 3.6.

Contract Compiling

To compile the contract, use:

• Shell

tronbox compile

By default, tronbox compiler only compiles modified contracts since last compile, to reduce unnecessary compiling. If you wish to compile the entire file, you can use --compile-all.

• Shell

tronbox compile --compile-all

The compile output is in ./build/contracts directory. If the directory doesn't exist, it will be auto-generated.

Contract Deployment

Script migration is with a JavaScript file composed to broadcast onto Tron network. The script migration caches your broadcast responsibility. Its existence is based on your broadcast needs and will adjust accordingly. When your work incurs significant change, the migration script you created will propagate the changes through the blockchain. Previous migration history records will undergo a unique Migrationscontract to be recorded on the blockchain. Below is a detailed instruction.

To initiate the migration, use the following command:

• Shell

tronbox migrate

This command will initiate all migration scripts within the migrationdirectory. If your previous migration was successful, tronbox migrate will initiate a new migration and use the development network by default.

If there is no new migration script, this command will have no operation. Instead, you can use — reset to re-deploy. You can also use — network NETWORK_NAME to specify a network. Eg. tronbox migrate --reset --network production

• Shell

PS  C:\**\bare-box> tronbox migrate --reset --network production
Using network 'production'.
Running migration: 1_initial_migration.js
  Deploying Migrations...
  Migrations: 41271233ac2eea178ec52f1aea64627630403c67ce
  Deploying Test...
  Test: 41477f693ae6f691daf7d399ee61c32832c0314871
Saving successful migration to network...
Saving artifacts...

Trigger Contract

The testing scripts are in the ./tests directory. TronBox will ignore all other extensions except for .js, .es, .es6, and .jsx
Below is an example testing script for test.js:

• test.js

var Test = artifacts.require("./Test.sol");
contract('Test', function(accounts) {
	it("call method g", function() {
	    Test.deployed().then(function(instance) {
		  return instance.call('g');
		}).then(function(result) {
		  assert.equal("method g()", result[0], "is not call method g");
	    });
	});
	it("call method f", function() {
	    Test.deployed().then(function(instance) {
		  return instance.call('f');
		}).then(function(result) {
		  assert.equal("method f()", result[0], "is not call method f");
		});
	});
});

Running Testing Script

• Shell

PS C:\**\bare-box> tronbox test ./test/test.js 
Using network 'production'.
  Contract: Test
    √ call method g
    √ call method f
  2 passing (23ms)