fix: lock js-component-bindgen version (#358)

* fix: lock js-component-bindgen version

Pin bindgen to v2.11.0 and require --locked in CI

* fix: explicitly configure splicer filesystem access

Newer preview2-shim releases no longer expose the host filesystem by
default, preventing the splicer from reading wit paths.

Author: andreiltd

.github/workflows/main.yml

@@ -34,7 +34,7 @@ jobs:
         run: cargo fmt -- --check
 
       - name: Run clippy
-        run: cargo clippy --workspace --all-targets --all-features
+        run: cargo clippy --locked --workspace --all-targets --all-features
 
   #########
   # Build #
@@ -59,7 +59,7 @@ jobs:
         uses: actions/cache@v4
         id: splicer-build
         with:
-          key: splicer-${{ matrix.os }}-${{ hashFiles('Cargo.lock', 'crates/spidermonkey-embedding-splicer/src/**/*.rs') }}
+          key: splicer-${{ matrix.os }}-${{ hashFiles('Makefile', 'Cargo.lock', 'crates/spidermonkey-embedding-splicer/src/**/*.rs') }}
           path: |
             lib
             target
@@ -134,7 +134,7 @@ jobs:
         uses: actions/cache/restore@v4
         id: splicer-build
         with:
-          key: splicer-${{ matrix.os }}-${{ hashFiles('Cargo.lock', 'crates/spidermonkey-embedding-splicer/src/**/*.rs') }}
+          key: splicer-${{ matrix.os }}-${{ hashFiles('Makefile', 'Cargo.lock', 'crates/spidermonkey-embedding-splicer/src/**/*.rs') }}
           path: |
             lib
             target
@@ -195,7 +195,7 @@ jobs:
         uses: actions/cache/restore@v4
         id: splicer-build
         with:
-          key: splicer-${{ matrix.os }}-${{ hashFiles('Cargo.lock', 'crates/spidermonkey-embedding-splicer/src/**/*.rs') }}
+          key: splicer-${{ matrix.os }}-${{ hashFiles('Makefile', 'Cargo.lock', 'crates/spidermonkey-embedding-splicer/src/**/*.rs') }}
           path: |
             lib
             target
@@ -239,7 +239,7 @@ jobs:
         uses: actions/cache/restore@v4
         id: splicer-build
         with:
-          key: splicer-${{ matrix.os }}-${{ hashFiles('Cargo.lock', 'crates/spidermonkey-embedding-splicer/src/**/*.rs') }}
+          key: splicer-${{ matrix.os }}-${{ hashFiles('Makefile', 'Cargo.lock', 'crates/spidermonkey-embedding-splicer/src/**/*.rs') }}
           path: |
             lib
             target

Cargo.lock

@@ -33,4 +33,4 @@ wit-parser = { version = "0.258.0", features = ["decoding", "serde"] }
 wit-bindgen = { version = "0.54.0", features = ["macros", "async", "realloc"] }
 wit-bindgen-core = { version = "0.61.1", default-features = false }
 
-js-component-bindgen = { version = "2.11.0" }
+js-component-bindgen = { version = "=2.11.0" }

Cargo.toml

@@ -17,12 +17,12 @@ debug: lib/starlingmonkey_embedding.debug.wasm lib/spidermonkey-embedding-splice
 release: lib/starlingmonkey_embedding.wasm lib/spidermonkey-embedding-splicer.js
 release-weval: lib/starlingmonkey_ics.wevalcache lib/spidermonkey-embedding-splicer.js
 
-lib/spidermonkey-embedding-splicer.js: target/wasm32-wasip1/release/splicer_component.wasm crates/spidermonkey-embedding-splicer/wit/spidermonkey-embedding-splicer.wit | obj lib
+lib/spidermonkey-embedding-splicer.js: Makefile target/wasm32-wasip1/release/splicer_component.wasm crates/spidermonkey-embedding-splicer/wit/spidermonkey-embedding-splicer.wit | obj lib
 	@$(JCO) new target/wasm32-wasip1/release/splicer_component.wasm -o obj/spidermonkey-embedding-splicer.wasm --wasi-reactor
-	@$(JCO) transpile -q --name spidermonkey-embedding-splicer obj/spidermonkey-embedding-splicer.wasm -o lib -- -O1
+	@$(JCO) transpile -q --instantiation async --no-wasi-shim --name spidermonkey-embedding-splicer obj/spidermonkey-embedding-splicer.wasm -o lib -- -O1
 
-target/wasm32-wasip1/release/splicer_component.wasm: Cargo.toml crates/spidermonkey-embedding-splicer/Cargo.toml crates/spidermonkey-embedding-splicer/src/*.rs crates/splicer-component/src/*.rs
-	cargo build --lib --release --target wasm32-wasip1
+target/wasm32-wasip1/release/splicer_component.wasm: Cargo.toml Cargo.lock crates/spidermonkey-embedding-splicer/Cargo.toml crates/spidermonkey-embedding-splicer/src/*.rs crates/splicer-component/src/*.rs
+	cargo build --locked --lib --release --target wasm32-wasip1
 
 lib/starlingmonkey_embedding.wasm: $(STARLINGMONKEY_DEPS) | lib
 	cmake -B build-release -DCMAKE_BUILD_TYPE=Release

Makefile

@@ -218,7 +218,8 @@ export function componentize(opts: {
    */
   sourcePath: string;
   /**
-   * Path to WIT file or folder
+   * Path to a WIT file or folder. Dependencies must be inside the given folder
+   * or, for a file, its parent folder. Subfolders are included.
    */
   witPath?: string;
   /**

README.md

@@ -7,7 +7,7 @@ export TEST_BINARY_PATH=$(realpath host)/target/release/wasmtime-test
 # Build the JS component if not present
 echo -e "[info] expecting component WASM at [$COMPONENT_WASM_PATH]...";
 if [ ! -f "$COMPONENT_WASM_PATH" ]; then
-    cd guest && npm install && npm run build && cd ..
+    cd guest && npm install --no-save ../../.. && npm run build && cd ..
 fi
 
 # Build the Rust embedding test binary if not present

examples/hello-world/test.sh

@@ -15,13 +15,13 @@
     "import": "./src/componentize.js"
   },
   "devDependencies": {
-    "@bytecodealliance/preview2-shim": "^0.17.4",
     "cross-env": "^7.0.3",
     "semver": "^7.7.2",
     "vitest": "^3.2.4"
   },
   "dependencies": {
     "@bytecodealliance/jco": "^1.15.1",
+    "@bytecodealliance/preview2-shim": "^0.29.0",
     "@bytecodealliance/weval": "^0.5.0",
     "@bytecodealliance/wizer": "^10.0.0",
     "es-module-lexer": "^1.6.0",

package-lock.json

@@ -19,7 +19,7 @@ import {
   preview1AdapterReactorPath,
 } from '@bytecodealliance/jco';
 
-import { splicer } from '../lib/spidermonkey-embedding-splicer.js';
+import { createSplicer } from './splicer.js';
 
 import { maybeWindowsPath } from './platform.js';
 
@@ -148,12 +148,16 @@ export async function componentize(
     features.delete('fetch-event');
   }
 
-  // Splice the bindigns for the given WIT world into the engine WASM
+  const { splicer, witPath: splicerWitPath } = await createSplicer(
+    witWorld == null ? witPath : undefined,
+  );
+
+  // Splice the bindings for the given WIT world into the engine WASM
   let { wasm, jsBindings, exports, imports } = splicer.spliceBindings(
     await readFile(engine),
     [...features],
     witWorld,
-    maybeWindowsPath(witPath),
+    splicerWitPath,
     worldName,
     false,
   );
@@ -393,7 +397,7 @@ export async function componentize(
     bin,
     [...features],
     witWorld,
-    maybeWindowsPath(witPath),
+    splicerWitPath,
     worldName,
   );
 

package.json

@@ -0,0 +1,34 @@
+import { readFile, realpath, stat } from 'node:fs/promises';
+import { basename, dirname } from 'node:path';
+import { WASIShim } from '@bytecodealliance/preview2-shim/instantiation';
+
+import { instantiate } from '../lib/spidermonkey-embedding-splicer.js';
+
+// Compiled modules can be shared, but instances must retain isolated preopens.
+const coreModules = new Map();
+
+function getCoreModule(name) {
+  if (!coreModules.has(name)) {
+    coreModules.set(
+      name,
+      readFile(new URL(`../lib/${name}`, import.meta.url)).then(WebAssembly.compile),
+    );
+  }
+  return coreModules.get(name);
+}
+
+export async function createSplicer(witPath) {
+  const preopens = {};
+  let guestWitPath;
+
+  if (witPath != null) {
+    const hostPath = await realpath(witPath);
+    const isDirectory = (await stat(hostPath)).isDirectory();
+    preopens['/wit'] = isDirectory ? hostPath : dirname(hostPath);
+    guestWitPath = isDirectory ? '/wit' : `/wit/${basename(hostPath)}`;
+  }
+
+  const wasi = new WASIShim({ sandbox: { preopens } });
+  const { splicer } = await instantiate(getCoreModule, wasi.getImportObject());
+  return { splicer, witPath: guestWitPath };
+}