Node bundling

[mrvicadai]

Other bundlers (like webpack) can target node environment instead of browser. That largely involves leaving things like require('fs') and process intact in the code.

Is there a way to do the same in fastpack?
If no, is it on the roadmap?

The use case is when writing a Node application using ReasonML, but don't want to bring the compiler with it when deploying, therefore need to bundle the js code.

[zindel]

Hi, @mrvicadai. Thanks for the request! Unfortunately, it is impossible in the fastpack at the moment. We've been targeting browsers first. There are some builtin (not pluggable) features which prevent an easy addition of the node target at the moment:

1. Fastpack considers the browser field.
2. Requiring fs, path and other builtin Node.js packages leads to an error with the suggestion of the browser-friendly mocks
3. process.env.NODE_ENV is replaced across the codebase with the constant (development or production) as well as non-matched if/ternary branches are pruned.

If I understand the feature request correctly, for the node target you definitely don't want (1). (2) should leave require statements intact. What about (3)? Is it desired behaviour or it should be skipped as well? Is there anything else specific about the node target?

[juancampa]

I'm also interested in targeting node. Another difference that comes to mind is window vs global as the global object. Not sure if that's builtin or not

[mrvicadai]

Hi @zindel thanks for the reply! I think you're correct that (1) and (2) are preventing node environment from working. Not necessarily (3) though since the application might need different configuration profiles depending on the environment.

@juancampa also made a good point that global is the "Pervasive" variable in Node, as well as __dirname and __filename as seen here.

[zindel]

@juancampa @mrvicadai could you suggest a reasonably simple (but still with some dependencies) app we could use for testing?

[mrvicadai]

@zindel I was looking at the source tree of the parcel bundler and found some integration test cases that might just serve as SSCCE for this:

• fs-alias
• fs-assign-alias
• fs-assign
• fs-buffer
• fs-destructure-assign
• fs-import
• fs-inline

In terms of real world example, I can think of this one as reasonably small, but very frequently used node package: https://github.com/isaacs/rimraf/blob/master/rimraf.js

[MoOx]

Also what could be interesting for (2) is that we have a way to ignore some require() to be considered. See https://arunoda.me/blog/ssr-and-server-only-modules for an example. Webpack have its IgnorePlugin for this purpose.