Truffle external scripts working example

If you getting errors bellow while trying to execute your truffle external script continue to read.

errors:

TypeError: Cannot read property 'apply' of undefined 

exception at require.js:128:1 

TypeError: fn is not a function 

For some reason it was quite difficult to find solution how to run external script. After some time I finally have figure it out so I'm sharing it with world:

	module.exports = function(callback) {
	let Web3 = require('web3');
	const truffleContract = require('truffle-contract')
	let contract = truffleContract(require('../build/contracts/MetaCoin.json'));
	var provider = new Web3.providers.HttpProvider("http://localhost:8545");
	var web3 = new Web3(provider);
	contract.setProvider(web3.currentProvider);
	//workaround: https://github.com/trufflesuite/truffle-contract/issues/57
	if (typeof contract.currentProvider.sendAsync !== "function") {
	contract.currentProvider.sendAsync = function() {
	return contract.currentProvider.send.apply(
	contract.currentProvider, arguments
	);
	};
	}
	contract.deployed().then(function(instance){
	return instance.yourFunction();
	}).then(response => {
	console.log(response);
	});
	}

view raw truffle-extenal.js hosted with ❤ by GitHub