@ue-shed/uasset-inspection-wasm

Portable WebAssembly inspection for classic, uncooked, versioned Unreal package bytes. The package accepts a Uint8Array and a display path; it does not discover files, read project roots, run processes, maintain caches, or write assets.

The first public contract is deliberately small:

• generic inspection returns schema 8;
• extractText and extractTextures return compact projection schema 1;
• malformed, unsupported, partial, and resource-limited packages are represented as typed result values;
• cooked, unversioned, IoStore/Zen, swapped-endian, and native bulk-data decoding remain outside the parser boundary.

The default input and serialized-output limit is 64 MiB. The Rust adapter also bounds package exports and compact projection records. JavaScript rejects an oversized Uint8Array before wasm-bindgen copies it into WebAssembly linear memory, and Rust stops JSON serialization when the output cap is reached instead of first constructing an oversized string.

These public limits compose with the parser's own ArchiveLimits: declared table/container counts are rejected before allocation, and nested property types, values, and struct fields are bounded by the parser. The WASM adapter calls the same Package::parse and decode_export paths; it adds host input/output, export, and projection caps rather than duplicating parser nesting or allocation policy.

Node

import {
	createNodeRuntime,
	inspect,
	extractText,
	extractTextures
} from "@ue-shed/uasset-inspection-wasm/node";

const runtime = createNodeRuntime();
const bytes = new Uint8Array(await readFile("Content/Fixture/Example.uasset"));
const inspection = runtime.inspect("Content/Fixture/Example.uasset", bytes);
const text = runtime.extractText("Content/Fixture/Example.uasset", bytes);

// The root Node entry exposes the same operations when a configured runtime is not needed.
const sameInspection = inspect("Content/Fixture/Example.uasset", bytes);
void extractTextures;
void sameInspection;

Browser

Use the explicit browser entry so bundlers do not select the Node loader:

import { createBrowserRuntime } from "@ue-shed/uasset-inspection-wasm/browser";

const runtime = await createBrowserRuntime();
const bytes = new Uint8Array(await (await fetch("/assets/Example.uasset")).arrayBuffer());
const inspection = runtime.inspect("Example.uasset", bytes);

The browser entry loads its adjacent .wasm file using import.meta.url. Servers should serve .wasm with application/wasm; the generated loader falls back to an ordinary fetch when streaming instantiation is unavailable.

WasmInputLimitError, WasmOutputLimitError, WasmProtocolError, and WasmInitializationError are thrown for host/runtime failures. Parser failures are returned as status: "error" values with schema-specific kind fields, so malformed input does not require exception-based control flow.

The npm package is MIT licensed. It is a read-only bytes-to-evidence adapter and does not publish the private Rust crate to crates.io.