rollup.config.js

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

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

const libraryName = 'esios-api';

var camelize = function camelize(str) {
    return str.toLowerCase().replace(/[^a-zA-Z0-9]+(.)/g, (_m, chr) => chr.toUpperCase());
};

export default {
    input: `src/${libraryName}.ts`,
    output: [
        { file: pkg.main, name: camelize(libraryName), format: 'umd', sourcemap: true },
        { file: pkg.module, format: 'es', sourcemap: true }
    ],
    // Indicate here external modules you don't wanna include in your bundle (i.e.: 'lodash')
    external: [],
    watch: {
        include: 'src/**'
    },
    plugins: [
        // Allow json resolution
        json(),
        // Compile TypeScript files
        typescript({ allowSyntheticDefaultImports: true }),
        // Allow bundling cjs modules (unlike webpack, rollup doesn't understand cjs)
        commonjs(),
        // 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(),

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