init

node_modules/@matrix-org/matrix-sdk-crypto-wasm/node.mjs

@@ -0,0 +1,125 @@
+// Copyright 2024 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// @ts-check
+
+/**
+ * This is the entrypoint on node-compatible ESM environments.
+ * `asyncLoad` will use `fs.readFile` to load the WASM module.
+ */
+
+import { fileURLToPath } from "node:url";
+import { readFileSync } from "node:fs";
+import { readFile } from "node:fs/promises";
+import * as bindings from "./pkg/matrix_sdk_crypto_wasm_bg.js";
+
+const filename = fileURLToPath(new URL("./pkg/matrix_sdk_crypto_wasm_bg.wasm", import.meta.url));
+
+// In node environments, we want to automatically load the WASM module
+// synchronously if the consumer did not call `initAsync`. To do so, we install
+// a `Proxy` that will intercept calls to the WASM module.
+bindings.__wbg_set_wasm(
+    new Proxy(
+        {},
+        {
+            get(_target, prop) {
+                const instance = loadModuleSync();
+                // @ts-expect-error: This results in an `any` type, which is fine
+                return instance[prop];
+            },
+        },
+    ),
+);
+
+/**
+ * Stores a promise which resolves to the WebAssembly module
+ * @type {Promise<WebAssembly.Module> | null}
+ */
+let modPromise = null;
+
+/**
+ * Tracks whether the module has been instantiated or not
+ * @type {boolean}
+ */
+let initialised = false;
+
+/**
+ * Loads and instantiates the WASM module synchronously
+ *
+ * It will throw if there is an attempt to load the module asynchronously running
+ *
+ * @returns {typeof import("./pkg/matrix_sdk_crypto_wasm_bg.wasm.d.ts")}
+ */
+function loadModuleSync() {
+    if (modPromise) throw new Error("The WASM module is being loaded asynchronously but hasn't finished");
+    const bytes = readFileSync(filename);
+    const mod = new WebAssembly.Module(bytes);
+
+    const instance = new WebAssembly.Instance(mod, {
+        // @ts-expect-error: The bindings don't exactly match the 'ExportValue' type
+        "./matrix_sdk_crypto_wasm_bg.js": bindings,
+    });
+
+    initInstance(instance);
+
+    // @ts-expect-error: Typescript doesn't know what the module exports are
+    return instance.exports;
+}
+
+/**
+ * Loads and instantiates the WASM module asynchronously
+ *
+ * @returns {Promise<typeof import("./pkg/matrix_sdk_crypto_wasm_bg.wasm.d.ts")>}
+ */
+async function loadModuleAsync() {
+    const bytes = await readFile(filename);
+    const { instance } = await WebAssembly.instantiate(bytes, {
+        // @ts-expect-error: The bindings don't exactly match the 'ExportValue' type
+        "./matrix_sdk_crypto_wasm_bg.js": bindings,
+    });
+
+    initInstance(instance);
+
+    // @ts-expect-error: Typescript doesn't know what the module exports are
+    return instance.exports;
+}
+
+/**
+ * Initializes the WASM module and returns the exports from the WASM module.
+ *
+ * @param {WebAssembly.Instance} instance
+ */
+function initInstance(instance) {
+    if (initialised) throw new Error("initInstance called twice");
+    bindings.__wbg_set_wasm(instance.exports);
+    // @ts-expect-error: Typescript doesn't know what the module exports are
+    instance.exports.__wbindgen_start();
+    initialised = true;
+}
+
+/**
+ * Load the WebAssembly module in the background, if it has not already been loaded.
+ *
+ * Returns a promise which will resolve once the other methods are ready.
+ *
+ * @returns {Promise<void>}
+ */
+export async function initAsync() {
+    if (initialised) return;
+    if (!modPromise) modPromise = loadModuleAsync();
+    await modPromise;
+}
+
+// Re-export everything from the generated javascript wrappers
+export * from "./pkg/matrix_sdk_crypto_wasm_bg.js";