build.js

#!/usr/bin/env node

const { build } = require('esbuild');
// const { fileURLToPath } = require('url');
const { existsSync } = require('fs');
const { resolve } = require('path');

const arg = process.argv;

const pkgJsonPath = resolve(process.cwd(), 'package.json');
const srcDir = resolve(process.cwd(), arg[2] || 'src');
const wfSrcDir = resolve(process.cwd(), arg[3] || arg[2] || 'src');
const outDir = resolve(process.cwd(), 'build');

(async () => {
  const paths = {
    packageJson: pkgJsonPath,
    indexTS: resolve(srcDir, 'index.ts'),
    workflowsFolderTS: resolve(wfSrcDir, 'workflows/index.ts'),
  };
  const workerTS = existsSync(paths.indexTS) ? paths.indexTS : null;
  const workflowsTS = existsSync(paths.workflowsFolderTS)
    ? paths.workflowsFolderTS
    : null;

  const packages = Object.keys(require(paths.packageJson).dependencies || {});
  if (!workerTS) throw new Error(`No worker found in ${srcDir}`);
  if (!workflowsTS) throw new Error(`No workflows found in ${srcDir}`);

  try {
    const t1 = build({
      bundle: true,
      sourcemap: true,
      entryPoints: [workerTS],
      outfile: resolve(outDir, 'index.js'),
      platform: 'node',
      external: packages.concat(['./workflows', '@temporalio/worker', '*.png']),
      treeShaking: true,
      target: 'node18',
      keepNames: true,
      format: 'cjs',
    });
    const t2 = build({
      bundle: true,
      sourcemap: true,
      format: 'esm',
      entryPoints: [workflowsTS],
      outfile: resolve(outDir, 'workflows.js'),
      platform: 'node',
      external: packages.concat(['@temporalio/workflow', '*.png']),
      treeShaking: true,
      target: 'node18',
      keepNames: true,
    });
    await Promise.all([t1, t2]);
    console.log('Build success');
  } catch (err) {
    console.error(err);
    process.exitCode = 1;
  }
})();