NodeJS usage not working in ESM

[nickpharrison]

Hi,

It appears as if NodeJS needs a helping hand to identify the NodeJS version of this library as commonjs rather than a module, since the package.json that's shipped with NPM listed "type": "module,".

I was able to get this working in NodeJS ESM by renaming node_modules\parquet-wasm\esm\parquet_wasm.js to have an extension of .cjs and replacing references in the package.json to use the new extension.

Unfortunately I'm not familiar enough with the build/bundle process for this module to be able to submit a PR myself.

Hopefully this would be a small change which would allow compatibility with modern NodeJS code.

[kylebarron]

👋 Thanks for the issue.

I'm not that familiar with JS bundling, and it seems like bundling best practices in the JS ecosystem change often.

Is there a reason why you can't use the parquet-wasm/node export, which is explicitly intended for Node?

[nickpharrison]

Hi, sorry I should have mentioned! This is when using the "parquet-wasm/node" bundling.

From what I can gather, the current set-up doesn't work with ESM unless I make the changes mentioned.

It's possible I'm doing something wrong, but I was able to replicate to two different computers. One Linux running Node v20, one Windows running Node v22.

[kylebarron]

Hmm. Does it work using the parquet-wasm/esm bundling? Perhaps we should document that parquet-wasm/node is intended for old-style require usage?

[matt-condon]

It seems a recent change in the published package has introduced "type": "module" which tells Node.js to treat all .js files as ES modules, but the node/parquet_wasm.js file that uses CommonJS syntax

Couldn't find a more apt approach, so I'm also using a workaround of a wrapper with a cjs extension so node Node.js always treats as CommonJS

npm install parquet-wasm@0.7.0 && cat node_modules/parquet-wasm/package.json

cat node_modules/parquet-wasm/package.json
{
  "name": "parquet-wasm",
  "collaborators": [
    "Kyle Barron <kylebarron2@gmail.com>"
  ],
  "description": "WebAssembly Parquet reader and writer.",
  "license": "MIT OR Apache-2.0",
  ...  
  "type": "module",
  "version": "0.7.0",
  "main": "parquet_wasm.js"
}

npm install parquet-wasm@0.6.1 && cat node_modules/parquet-wasm/package.json

{
  "name": "parquet-wasm",
  "collaborators": [
    "Kyle Barron <kylebarron2@gmail.com>"
  ],
  "description": "WebAssembly Parquet reader and writer.",
  "license": "MIT OR Apache-2.0",
  ...
  "version": "0.6.1"
}

[kylebarron]

Thanks for looking into this. I don't know enough about JS bundling; is the solution just to take out the "type": "module"? I.e. we want that for the esm and bundler entry points but not the node entry point?

[matt-condon]

Yep I'm pretty sure that would work!

[kylebarron]

Would you be able to try #807 ?

You should be able to build it with yarn build, which will put it into the pkg directory.

On Mac you may need to set env vars, as described here