Support both Node.js runtime and bundlers by default, out-of-the-box

[KSXGitHub]

When I write an NPM package, I rarely think of bundlers as they can comprehend require() syntax, so as long as I only use require() to load module, I don't worry about bundlers. This is not the case with Node.js WASM modules generated by wasm-bindgen as it uses fs.readFileSync (which cannot be polyfilled by bundlers) to load .wasm file.

wasm-pack build currently supports 2 targets:

• --target browser support bundlers (today's browsers cannot load the output script/module directly) but not Node.js.
• --target nodejs support Node.js runtime but not bundlers/browsers.

This is inconvenient, if I want to support both targets, I have to write my own wrapper that calls wasm-bindgen twice.

Suggestion

• Without options, generate 4 files for 4 targets:

  • index.bundler.js for JavaScript bundlers, set "browser" field in package.json to point to this file.
  • index.js for Node.js runtime, set "main" field in package.json to point to this file.
  • index.mjs to work with node --experimental-module, "module" field of package.json may or may not point to this file.
  • index.script.js to work with <script> tag (I want to be able to test this directly in browser console).

• Deprecate the use of --target <target> in favor of --nodejs index.js, --module index.mjs, --browser index.bundler.js, and --script index.script.js.

Additional Suggestion

Please don't use package name in Cargo.toml for JavaScript entry files, use index.* like most NPM packages.

[ashleygwilliams]

hi @KSXGitHub ! this is a pretty common request that we get and something we fully intend to implement starting after the most recent release comes out!

[KSXGitHub]

@ashleygwilliams Since you tagged this as "duplicate", can you also give me the link to the original issue?

BTW, this issue isn't a mere request, but also a small suggestion of how this could be implemented.

[ashleygwilliams]

#157

and i understand that it's a suggestion for implementation- we already have a pretty good idea of how we'd like to do this (very similar to what you have suggested- except we are not interested in supporting .mjs at this time) - just need to do it!

[KSXGitHub]

@ashleygwilliams Thanks.

except we are not interested in supporting .mjs at this time

What prevents you guy from doing this?

[ashleygwilliams]

i think at the moment it's still experimental and in the interest of keeping wasm-pack simple, we don't want to support experimental targets. once node stabilizes it we'll add support.

[ashleygwilliams]

closing in favor of #313 - going to copy your suggestions here into a comment on that issue. looking to do this for the 0.10.0 release