mediainfo.js 0.3.5 giving error loading MediaInfoModule.wasm

I have an AWS javascript lambda using CommonJS modules running under Node.js 18.x. (I know it's a bit old and just went out of support). I'm running currently with mediainfo.js 0.1.9 and everything works fine. I tried to upgrade to mediainfo.js 0.3.5 and, after making appropriate adjustments (like changing new MediaInfoFactory(..) to mediaInfoFactory(..)), I get the following errors when I'm trying to run:

2025-07-25T05:29:49.977Z    da5eb22d-0494-41dd-8aa8-194b0e8b42be    ERROR   failed to asynchronously prepare wasm: CompileError: WebAssembly.instantiate(): invalid value type 0x64 @+249

2025-07-25T05:29:49.977Z    da5eb22d-0494-41dd-8aa8-194b0e8b42be    ERROR   Aborted(CompileError: WebAssembly.instantiate(): invalid value type 0x64 @+249)

2025-07-25T05:29:49.977Z    da5eb22d-0494-41dd-8aa8-194b0e8b42be    ERROR   RuntimeError: Aborted(CompileError: WebAssembly.instantiate(): invalid value type 0x64 @+249). Build with -sASSERTIONS for more info.
    at abort (/var/task/node_modules/mediainfo.js/dist/cjs/MediaInfoModule.cjs:297:15)
    at instantiateArrayBuffer (/var/task/node_modules/mediainfo.js/dist/cjs/MediaInfoModule.cjs:343:9)
    at async createWasm (/var/task/node_modules/mediainfo.js/dist/cjs/MediaInfoModule.cjs:417:22)
    at async /var/task/node_modules/mediainfo.js/dist/cjs/MediaInfoModule.cjs:2645:23

I temporarily built a custom locateFile function and passed it to the 0.3.5 mediaInfoFactory and I verified that I'm loading MediaInfoModule.wasm from the correct location. I also verified that offset 249 (decimal) = 0xf9 (hex) indeed contains a x'64'.

The error is on this statement: let mi = await mediaInfoFactory({chunkSize: CHUNK_SIZE, coverData: false, format: 'JSON'});

and the require that I'm using is: const { mediaInfoFactory } = require('mediainfo.js');

I'm not sure what I'm doing wrong or if it's something with my environment or what.

I appreciate any help. Thanks, Gary

Solution

TL;DR Node 18 is not supported.

👉️ Solution: Switch to at least Node 20 or use an older release of mediainfo.js.

Explanation:

0x64 (decimal 100) is the LEB-128 encoded value of the type externref in the WebAssembly binary.

Node 18’s V8 (8.9-ish) was released before the reference-types proposal reached phase-4, so the byte that encodes externref is illegal → the decoder throws "invalid value type".

0x64 is one byte in the .wasm file.
The parser is at offset 249 in the type section (section id 1).
Every function signature starts with its parameter/result types; the spec says that a type byte must be one of
- 0x7F i32
- 0x7E i64
- 0x7D f32
- 0x7C f64

or, if the engine understands the reference-types proposal, the new type bytes

0x6F funcref
0x64 externref

V8 8.9 (Node 18) does not know those two new bytes, so 0x64 is simply illegal and the whole module is rejected.

Full disclosure: I am the maintainer of mediainfo.js.