Unable to use WASM module

[rygine]

source code here: https://github.com/xmtp/snap
branch: rygine/upgrade-sdk

i recently upgraded our SDK for use with a snap and the WASM integration has stopped working.

our SDK now includes 2 different ways to access the WASM module via wasm-pack build targets.

when using the bundler target (which was the previously used target), i'm seeing this error when attempting to access the WASM bindings: MetaMask - RPC Error: Cannot read properties of undefined (reading '__wbindgen_add_to_stack_pointer')

the snap manifest hasn't changed and includes the webassembly endowment.

the snap config also includes the experiment wasm support flag.

if i attempt to use the web target, which fetches the WASM module via new URL(...) and fetch, i'm seeing a different error: MetaMask - RPC Error: Failed to construct 'URL': Invalid URL.

for this error, the issue seems to be that import.meta.url is translated to a local file path: file:///Users/user/Projects/snap/node_modules/@xmtp/user-preferences-bindings-wasm/dist/web/user_preferences_bindings_wasm.js, which is not accessible from within the snap.

i would prefer to use the web targeted WASM module, but understand if that's not possible.

please advise, thanks!

[Mrtenz]

I tried to reproduce using @xmtp/user-preferences-bindings-wasm, but I can't get the Snap to build, probably because it's an ESM package now, whereas xmtp-js bundles it. Do you have a simple way to reproduce the error with xmtp-js?

✖ Compiled 1 file in 126ms with 1 error.

  • Module not found: Error: Package path ./bundler is not exported from package ./node_modules/@xmtp/user-preferences-bindings-wasm (see exports field in ./node_modules/@xmtp/user-preferences-bindings-wasm/package.json)

[rygine]

hmm, that error seems to be because the standard node module resolver can't resolve the exports field in package.json. have you tried changing moduleResolution to Bundler?

[rygine]

this has been resolved. it was an issue with sideEffects: false being set in package.json. for wasm-pack builds using the bundler option, webpack will tree-shake necessary code when this option is set.

also, using the web option in wasm-pack is not supported due to the use of import.meta.url.

thank you to @Mrtenz for help in debugging this issue!