rollup.config.ts

import resolve from 'rollup-plugin-node-resolve';
import commonjs from 'rollup-plugin-commonjs';
import sourceMaps from 'rollup-plugin-sourcemaps';
import typescript from 'rollup-plugin-typescript2';
import json from 'rollup-plugin-json';

const pkg = require('./package.json');

const banner = `/*!
 * ${pkg.title} ${pkg.version} <${pkg.homepage}>
 * Copyright (c) ${(new Date()).getFullYear()} ${pkg.author.name} <${pkg.author.url}>
 * Released under ${pkg.license} License
 */`;

export default {
    input: `src/index.ts`,
    output: [
        { file: pkg.main, name: pkg.name, format: 'umd', banner, sourcemap: true },
        { file: pkg.module, format: 'esm', banner, sourcemap: true },
    ],
    external: [],
    watch: {
        include: 'src/**',
    },
    plugins: [
        // Allow node_modules resolution, so you can use 'external' to control
        // which external modules to include in the bundle
        // https://github.com/rollup/rollup-plugin-node-resolve#usage
        resolve(),
        // Allow json resolution
        json(),
        // Compile TypeScript files
        typescript({ useTsconfigDeclarationDir: true }),
        // Allow bundling cjs modules (unlike webpack, rollup doesn't understand cjs)
        commonjs({
            include: 'node_modules/**'
        }),

        // Resolve source maps to the original source
        sourceMaps(),
    ],
}