Support generating a UMD bundle

[ghost]

Choose one: feature request?

Right now, parcel is used for compiling code to be used for a frontend server. There's no way to create a named library that you can use drop in a <script src='...'> tag and call via myLibrary.Foo(). Both rollup and webpack allow you to specify a config similar to

output: {
    file: 'dist/styled-components.js',
    format: 'umd',
    name: 'styled',
    exports: 'named',
}

It would be awesome if parcel supported something similar and wasn't strictly for server/html code.

[danawoodman]

I too would be able to use Parcel more if this was supported. It is equivalent to WebPack's output.library option.

[devongovett]

Related: #453

[willin]

It is also equivalent to Rollup's output.format option.

https://rollupjs.org/guide/en#command-line-flags

• -f, --output.format [es] Type of output (amd, cjs, es, iife, umd)
• -n, --name Name for UMD export

[devongovett]

Fixed by #453. Modules are now exposed to CommonJS and AMD automatically, and if you specify a --global <name> flag, as a global variable.

[willin]

UMD...

[random-yang]

Fixed by #453. Modules are now exposed to CommonJS and AMD automatically, and if you specify a --global <name> flag, as a global variable.

This work for me, but there sames no way to expose myvariable on the globle window.

// lib.js

export default { ... }

then run parcel build lib.js --global mylib

<!-- index.htm -->
<script src'./lib.js'></script>
<script>
console.log(mylib)
</script>

the out put is:

Now I wanna use is have to code mylib.default, which is really wired.
How can I make mylib is mylib.default‘'s value.

Thanks !

[mischnic]

You cannot use ESM exports for that. module.exports = ... would make it available as mylib.

[niieani]

@devongovett is UMD still supported in Parcel 2? I see no mention of it in the docs - should we re-open this issue? Thanks! 🙇

[danmarshall]

@niieani - I'm not sure why this is not in V2, but here is my workaround:

window['MyGlobalName'] = myGlobalVar;

[zhaoyao91]

@niieani - I'm not sure why this is not in V2, but here is my workaround:

window['MyGlobalName'] = myGlobalVar;

Need umd/iife format in v2
it is expected to bundle all dependencies into the final bundle expect the native node modules.
I guess your workaround won't handle the dependencies bundling problem.