rollup.config.js

import resolve from '@rollup/plugin-node-resolve';
import typescript from 'rollup-plugin-typescript2';
import commonjs from '@rollup/plugin-commonjs';
import json from '@rollup/plugin-json';
import { terser } from 'rollup-plugin-terser';
import pkg from './package.json';

const external = ['assert'];

const banner = `/*!
 * ${pkg.name} v${pkg.version}
 * github.com/samber/chartjs-plugin-datasource-prometheus
 * (c) ${new Date().getFullYear()} chartjs-plugin-datasource-prometheus Contributors
 * Released under the MIT License
 */`;

export default [
	// browser-friendly UMD build
	{
		input: 'src/index.ts',
		output: [
			{
				name: 'ChartDatasourcePrometheusPlugin',
				file: pkg.browser,
				format: 'umd',
				banner,
				globals: {
					'chart.js': 'Chart',
				},
				sourcemap: true,
			},
		],
		external: [
			'chart.js',
		],
		plugins: [
            json(),
            // so Rollup can find `axios`
			resolve({
				browser: true,
			}),
            typescript({
                useTsconfigDeclarationDir: true,
                tsconfigOverride: { compilerOptions : { module: 'es2015' } }
            }),
            // so Rollup can convert `axios` to an ES module
            commonjs({
                extensions: ['.js', '.ts']
            }),
            terser({
				output: {
					preamble: banner
				}
			}),
		],
	},

	// CommonJS (for Node) and ES module (for bundlers) build.
	// (We could have three entries in the configuration array
	// instead of two, but it's quicker to generate multiple
	// builds from a single configuration where possible, using
	// an array for the `output` option, where we can specify
	// `file` and `format` for each target)
	{
		input: 'src/index.ts',
		external: [],
		output: [
			{
				file: pkg.main,
				format: 'cjs',
				globals: {
					'chart.js': 'Chart',
				},
                sourcemap: true,
			},
			{
				file: pkg.module,
				format: 'es',
				globals: {
					'chart.js': 'Chart',
				},
                sourcemap: true,
			}
		],
		external: [
			'chart.js',
		],
        plugins: [
            typescript({
                tsconfigOverride: { compilerOptions : { module: "es2015" } },
            }),
        ],
	}
];