build-cdn.js

import path from 'path';
import esbuild from 'esbuild';
import glob from 'tiny-glob';
import pkg from './packages/plainjs/package.json' assert { type: 'json' };

const replaceDependenciesByJsdelivr = {
  name: 'replace-dependencies-by-jsdelivr',
  setup(build) {
    build.onResolve({ namespace: 'file', filter: /^@json2csv\/.*$/ }, async (args) => {
      if (args.kind !== 'import-statement') return;
      
      const [, relativePath] = args.path.match(/\@json2csv\/(.*)/);
      return {
        path: path.join('..', relativePath, 'index.js'),
        external: true,
        namespace: 'dependency',
      };
    });

    build.onResolve({ namespace: 'file', filter: /^\.\/.*$/ }, (args) => {
      if (args.kind !== 'import-statement') return;

      return {
        path: args.path,
        external: true,
        namespace: 'dependency',
      };
    });

    const dependencies = {
      '@streamparser/json': `https://cdn.jsdelivr.net/npm/@streamparser/json@${pkg.dependencies['@streamparser/json']}/dist/mjs/index.js`
    };

    build.onResolve({ namespace: 'file', filter: new RegExp(`(?:${Object.keys(dependencies).join('|')})`) }, (args) => {
      if (args.kind !== 'import-statement') return;

      if (dependencies[args.path]) {
        return {
          path: dependencies[args.path] || args.path,
          external: true
        };
      }
    });
  },
};

const pkgs = ['plainjs', 'whatwg', 'transforms', 'formatters'];

pkgs.forEach(async (pkg) => {
  const entryPoints = await glob(`packages/${pkg}/src/*.ts`);
  esbuild.build({
    entryPoints,
    bundle: true,
    target: 'es2019',
    format: 'esm',
    outdir: `dist/cdn/${pkg}`,
    plugins: [replaceDependenciesByJsdelivr],
  }).catch((err) => {
    console.error(err);
    process.exit(1);
  });
});