ESM broken - Githubissues

thantos commented 1 year ago

What were you trying to do?

Use pdf-lib in node 18 with esm, esbuild (esm) to bundle, and run locally with nodejs in esm.

How did you attempt to do it?

import {PDFDocument} from "@cantoo/pdf-lib"

import PdfLib from "@cantoo/pdf-lib"
const {PDFDocument} = PdfLib;

import * as  PdfLib from "@cantoo/pdf-lib"

What actually happened?

Outcome of the import patterns in order

node 18 complains that the module is CJS and destructuring isn't supported
works for node, but esbuild complains that there is no default export for es/index.js
works for esbuild, but at runtime with esm on nodejs, all of the exports are undefined (because there is no default export).

What did you expect to happen?

I expect at least import pattern 1 to work.

How can we reproduce the issue?

index.mjs:

import { PDFDocument } from "@cantoo/pdf-lib";
PDFDocument.create();

{
  "name": "pdf-lib-sample",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "type": "module",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "devDependencies": {
    "@cantoo/pdf-lib": "^1.19.11",
  },
  "author": "",
  "license": "ISC"
}

npm i node index.mjs

Version

=1.19

What environment are you running pdf-lib in?

Node, Other

Checklist

[X] My report includes a Short, Self Contained, Correct (Compilable) Example.
[X] I have attached all PDFs, images, and other files needed to run my SSCCE.

Additional Notes

For typescript to recognize the es/index.js import, it needs a package.json with { type: "module" } in the directory at a minimum.

For node, it needs the new "exports" block in package.json

  "exports": {
    ".": {
      "types": "./cjs/index.d.ts",
      "require": "./cjs/index.js",
      "import": "./es/index.js"
    }
  },

Additionally, the es/* directory imports need to be updated to use full file paths.

Error [ERR_MODULE_NOT_FOUND]: Cannot find module '[redacted]/pdf-lib-sample/node_modules/@cantoo/pdf-lib/es/core/errors' imported from [redacted]/pdf-lib-sample/node_modules/@cantoo/pdf-lib/es/core/index.js

Is fixed by changing es/index.js to:

export * from './api/index.js';
export * from './core/index.js';
export * from './types/index.js';
export * from './utils/index.js';

But needs to be repeated all of the way down.

My current resolution is to downgrade back to 1.17, which does not have this issue.