`pouchdb-utils` depends on `events` npm package for the browser build, but does not declare it as a dependency.

[lgarron]

Issue

Bundle pouchdb-utils using a typical bundler. For example, bundle using esbuild with the following commands:

mkdir -p /tmp/dependency-repro && cd /tmp/dependency-repro
npm init -y
npm install pouchdb-utils esbuild
echo 'export * from "pouchdb-utils";' | npx esbuild --format=esm --target=es6 --bundle --minify

This results in:

✘ [ERROR] Could not resolve "events"

    node_modules/pouchdb-utils/lib/index-browser.es.js:2:25:
      2 │ import EventEmitter from 'events';
        ╵                          ~~~~~~~~

  The package "events" wasn't found on the file system but is built into node.
  Are you trying to bundle for node? You can use "--platform=node" to do that,
  which will remove this error.

1 error

Note that the suggested --platform=node argument is not appropriate, as this is happening while bundling the browser build.

It seems the browser build of pouchdb-utils expects the package events from npm to be installed as a polyfill for node's built-in node:events module. This is not good practice, and I think pouchdb-utils should explicitly declare this dependency so that its browser build has all required dependencies.

(It may also be wise to conditionally load the polyfill only when node:events is not available, but that isn't necessary for this issue.)

Info

• Environment: macOS 14.6.1
• Platform: macOS 14.6.1
• Adapter: N/A
• Server: N/A

Reproduce

See above

---

I would try to submit a PR to address this, but I can't figure out how package.json for pouchdb-utils is synthesized.

[lgarron]

Okay, it looks like this code tries to skip built-in node modules:

https://github.com/pouchdb/pouchdb/blob/14a566f2e7bb780c1af37fd468f419f029a0adc5/bin/build-module.js#L43-L44

I don't know how to submit a simple PR for this, as unfortunately I think this is an outdated approach to dependency handling. I think it would be better to distinguish between actual node modules and their polyfills:

• Explicitly use node: protocol imports whenever importing code that is only meant to be imported in a node-compatible runtime (e.g. node or bun).
• Audit which polyfill dependencies are needed for browser builds.
• Update the code above to declare node:* modules as external instead of the same-named polyfills.

This may require some of the code to be refactored to perform a conditional import based on the runtime. Alternatively, it may be simpler for this particular code to declare keep import of events and allow runtimes to map this to built-in modules (ignoring the npm package)` if they want.