extract-types.mjs

import fs from 'node:fs';
import path from 'node:path';

/**
 * This is used to extract the type declarations from the openai Node.js
 * package. Doing this allows it to be a devDependency instead of a dependency,
 * which greatly reduces the size of the final bundle.
 */
function extractTypes(srcDir, destDir) {
  if (!fs.existsSync(destDir)) {
    fs.mkdirSync(destDir, { recursive: true });
  }

  const entries = fs.readdirSync(srcDir, { withFileTypes: true });

  for (const entry of entries) {
    const srcPath = path.join(srcDir, entry.name);
    const destPath = path.join(destDir, entry.name);

    if (entry.isDirectory()) {
      extractTypes(srcPath, destPath);
    } else if (entry.isFile() && entry.name.endsWith('.d.ts')) {
      const depth = Math.max(0, destPath.split('/').length - 2);
      const relativePath = depth > 0 ? '../'.repeat(depth) : './';

      // OpenAI has some absolute package imports, so switch them to use relative imports.
      const content = fs
        .readFileSync(srcPath, 'utf8')
        .replaceAll(/'openai\/([^'.]*)'/g, `'${relativePath}$1.js'`);
      fs.writeFileSync(destPath, content);
      console.log(destPath);
    }
  }
}

extractTypes('node_modules/openai', 'openai-types');