rollup.config.ts

import external from 'rollup-plugin-peer-deps-external'
import resolve from 'rollup-plugin-node-resolve'
import commonjs from 'rollup-plugin-commonjs'
import sourceMaps from 'rollup-plugin-sourcemaps'
import camelCase from 'lodash.camelcase'
import typescript from 'rollup-plugin-typescript2'
import json from 'rollup-plugin-json'

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

const libraryName = 'sanity-plugin-asset-source-unsplash'

export default {
  input: `src/index.ts`,
  output: [
    {
      file: pkg.main,
      name: camelCase(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: [
    '@sanity/base',
    '@sanity/components',
    'lodash',
    'react-dom',
    'react',
    'rxjs',
    '@sanity/ui',
    'styled-components'
  ],
  watch: {
    include: 'src/**'
  },
  plugins: [
    external(),
    // 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/**',
      namedExports: {
        'node_modules/react-is/index.js': ['isValidElementType']
      }
    }),
    // 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()
  ]
}