The contract JSON ABIs generated by Truffle contain sensitive and private informations: the File system path of the developer’s computer/machine. This scripts remove these sensitive entries and reduces by quite few MB the size of the contracts JSON ABIs in the process. (original source: https://github.com/ERC725Alliance/ERC725/pull/71/commits/1b…

reduce-truffle-artifacts.js

/**
 * This script removes source + AST entries inside the JSON artifacts generated by `truffle conpile`
 * It will make artifacts files smaller in size (truffle generated ABI files usually
 * contain around 5,000 to 20,000 lines).
 *
 * It is useful when deploying to a package registry like npm, as it helps to:
 *  - optimize package size
 *  - generate safer to use artifacts, as some artifact files contain sensitive informations
 *      (they key "sourcePath" in the artifacts generated by truffle contains the File system path
 *      of the user that compiled the contracts via `truffle compile` command)
 *
 * @see Github https://github.com/trufflesuite/truffle/issues/1269
 */
const fs = require('fs');
const TruffleConfig = require('@truffle/config');

// find config file & return new TruffleConfig object with config file settings (cwd)
const truffleConfig = TruffleConfig.detect();
const artifactsFolder = truffleConfig.contracts_build_directory;

function generateSmallerArtifact(_file) {
	fs.readFile(_file, (err, fileContent) => {
		if (err) console.error(`Error reading file: ${err}`);

		let jsonArtifact = JSON.parse(fileContent);
		removeSourcesEntries(jsonArtifact);
		removeASTEntries(jsonArtifact);

		fs.writeFile(_file, JSON.stringify(jsonArtifact), (err) => {
			err |
				console.log(
					'\u2713 Smaller JSON artifact created for -> ',
					_file.replace(artifactsFolder + '/', ''),
				);
		});
	});
}

function removeSourcesEntries(_content) {
	const sourceEntries = [
		'generatedSources',
		'deployedGeneratedSources',
		'sourceMap',
		'deployedSourceMap',
		'source',
		'sourcePath',
	];
	sourceEntries.map((entry) => delete _content[entry]);
}

function removeASTEntries(_content) {
	const astEntries = ['ast', 'legacyAST'];
	astEntries.map((entry) => delete _content[entry]);
}

fs.readdir(artifactsFolder, (err, files) => {
	if (err) console.error(`Error reading 'artifacts/' directory: ${err}`);
	for (const file of files) {
		generateSmallerArtifact(artifactsFolder + '/' + file);
	}
});