Support vendoring modules which read "static" files, like .wasm

[GJZwiers]

I would like to deno vendor a module that uses WebAssembly (WASM). It is compiled using wasm-bindgen so there is a directory structure like this:

pkg/
├── file.js
├── file_bg.wasm
├── file.d.ts

The .js file contains glue code that calls into the .wasm file. It is vendored successfully but tries to fetch the WASM from a URL like this:

input = new URL('file_bg.wasm', import.meta.url);

Unfortunately, after vendoring the URL points to a path in the local filesystem, but nothing is there because the .wasm file isn't brought over. So it is not possible to run the module locally after vendoring.

[kitsonk]

Hmmm... vendoring remote modules that read "static" files would be complex, but I can see the need.

@dsherret thoughts?

[mlafeldt]

Noticed this problem today when trying to vendor eszip:

❯ deno vendor https://deno.land/x/[email protected]/mod.ts
Vendored 3 modules into vendor/ directory.

To use vendored modules, specify the `--import-map` flag when invoking deno subcommands:
  deno run -A --import-map vendor/import_map.json main.ts

❯ tree vendor/
vendor/
├── deno.land
│   └── x
│       └── [email protected]
│           ├── eszip_wasm.generated.js
│           ├── loader.ts
│           └── mod.ts
└── import_map.json

3 directories, 4 files

Since https://deno.land/x/[email protected]/eszip_wasm_bg.wasm isn't downloaded, the vendored version of eszip is broken.

[bartlomieju]

I believe this will have to wait for #2552

[CreatCodeBuild]

Any update on this?

[petamoriken]

I believe we need to wait for Import Attributions (a.k.a Import Assertions).

[dsherret]

Actually, yeah this would be supported by #2552. For now, this can be solved by manually running a custom post-vendoring step to download the necessary .wasm files.

[serhalp]

@dsherret now that #26668 has landed, can we reopen this issue? 👀

[dsherret]

I don't think there's anything actionable in this issue. With Wasm modules this now works, but they need to be imported using Wasm imports.

For static files, follow #25354

[serhalp]

@dsherret Ah, my bad — you're saying that when WASM support landed, WASM vendoring support landed too? In that case, carry on :)