Feature/workers optimised

lib/package.json

@@ -53,8 +53,8 @@
     "lint": "eslint ./src/**/*.ts ./tdf3/**/*.ts ./tests/**/*.ts",
     "prepack": "npm run build",
     "test": "npm run build && npm run test:mocha && npm run test:wtr && npm run test:browser && npm run coverage:merge",
-    "test:browser": "node dist/web/tests/server.js & trap \"node dist/web/tests/stopServer.js\" EXIT; npx webpack --config webpack.test.config.cjs && npx karma start karma.conf.cjs",
-    "test:mocha": "node dist/web/tests/server.js & trap \"node dist/web/tests/stopServer.js\" EXIT; c8 --exclude=\"dist/web/tests/\" --exclude=\"dist/web/tdf3/src/utils/aws-lib-storage/\"  --exclude=\"dist/web/tests/**/*\" --report-dir=./coverage/mocha mocha 'dist/web/tests/mocha/**/*.spec.js' --file dist/web/tests/mocha/setup.js && npx c8 report --reporter=json --report-dir=./coverage/mocha",
+    "test:browser": "node --require ./preServer.js dist/web/tests/server.js & trap \"node dist/web/tests/stopServer.js\" EXIT; npx webpack --config webpack.test.config.cjs && npx karma start karma.conf.cjs",
+    "test:mocha": "node --require ./preServer.js dist/web/tests/server.js & trap \"node dist/web/tests/stopServer.js\" EXIT; c8 --exclude=\"dist/web/tests/\" --exclude=\"dist/web/tdf3/src/utils/aws-lib-storage/\"  --exclude=\"dist/web/tests/**/*\" --report-dir=./coverage/mocha mocha 'dist/web/tests/mocha/**/*.spec.js' --file dist/web/tests/mocha/setup.js && npx c8 report --reporter=json --report-dir=./coverage/mocha",
     "test:wtr": "web-test-runner",
     "watch": "(trap 'kill 0' SIGINT; npm run build && (npm run build:watch & npm run test -- --watch))"
   },
@@ -69,6 +69,7 @@
     "dpop": "^1.2.0",
     "events": "^3.3.0",
     "jose": "^4.14.4",
+    "p-limit": "^5.0.0",
     "streamsaver": "^2.0.6",
     "uuid": "~9.0.0"
   },
@@ -98,6 +99,7 @@
     "colors": "^1.4.0",
     "eslint": "^8.46.0",
     "eslint-config-prettier": "^8.9.0",
+    "fetch-blob": "^4.0.0",
     "glob": "^10.3.3",
     "jsdom": "^22.1.0",
     "karma": "^6.4.2",

lib/preServer.js

@@ -0,0 +1 @@
+import('./dist/web/tests/mocha/setup.js').catch(e => console.error(e));

lib/tdf3/src/crypto/decrypt-worker.ts

@@ -0,0 +1,75 @@
+import { TdfDecryptError } from '../../../src/errors.js';
+
+const maxWorkers = navigator?.hardwareConcurrency || 4; // save fallback number
+
+interface DecryptData {
+  key: CryptoKey;
+  encryptedPayload: ArrayBuffer;
+  algo: AesCbcParams | AesGcmParams;
+}
+
+const workerScript = `
+  self.onmessage = async (event) => {
+    const { key, encryptedPayload, algo } = event.data;
+
+    try {
+      const decryptedData = await crypto.subtle.decrypt(algo, key, encryptedPayload);
+      self.postMessage({ success: true, data: decryptedData });
+    } catch (error) {
+      self.postMessage({ success: false, error: error.message });
+    }
+  };
+`;
+
+const workerBlob = new Blob([workerScript], { type: 'application/javascript' });
+const workerUrl = URL.createObjectURL(workerBlob);
+const workersArray: Worker[] = Array.from({ length: maxWorkers }, () => new Worker(workerUrl));
+
+interface WorkersQueue {
+  freeWorkers: Worker[];
+  resolvers: ((worker: Worker) => void)[];
+  push: (worker: Worker) => void;
+  pop: () => Promise<Worker>;
+}
+
+export const workersQueue: WorkersQueue = {
+  freeWorkers: [...workersArray],
+  resolvers: [],
+
+  push(worker: Worker) {
+    const resolve = this.resolvers.shift();
+    if (typeof resolve === 'function') {
+      resolve(worker);
+    } else {
+      this.freeWorkers.push(worker);
+    }
+  },
+
+  pop(): Promise<Worker> {
+    return new Promise((resolve) => {
+      const worker = this.freeWorkers.shift();
+      if (worker instanceof Worker) {
+        resolve(worker);
+      } else {
+        this.resolvers.push(resolve);
+      }
+    });
+  },
+};
+
+export async function decrypt(data: DecryptData): Promise<ArrayBuffer> {
+  const worker: Worker = await workersQueue.pop();
+  return await new Promise((resolve, reject) => {
+    worker.onmessage = (event) => {
+      const { success, data, error } = event.data;
+      workersQueue.push(worker);
+      if (success) {
+        resolve(data as ArrayBuffer);
+      } else {
+        reject(new TdfDecryptError(error));
+      }
+    };
+
+    worker.postMessage(data);
+  });
+}

lib/tdf3/src/crypto/index.ts

@@ -5,6 +5,7 @@
  */
 
 import { Algorithms } from '../ciphers/index.js';
+import { decrypt as workerDecrypt } from './decrypt-worker.js';
 import { Binary } from '../binary.js';
 import {
   CryptoService,
@@ -274,17 +275,23 @@ async function _doDecrypt(
   const importedKey = await _importKey(key, algoDomString);
   algoDomString.iv = iv.asArrayBuffer();
 
-  const decrypted = await crypto.subtle
-    .decrypt(algoDomString, importedKey, payloadBuffer)
-    // Catching this error so we can specifically check for OperationError
-    .catch((err) => {
-      if (err.name === 'OperationError') {
-        throw new TdfDecryptError(err);
-      }
-
-      throw err;
-    });
-  return { payload: Binary.fromArrayBuffer(decrypted) };
+  try {
+    const decrypted = navigator?.hardwareConcurrency
+      ? await workerDecrypt({
+          key: importedKey,
+          encryptedPayload: payloadBuffer,
+          algo: algoDomString,
+        })
+      : await crypto.subtle.decrypt(algoDomString, importedKey, payloadBuffer);
+
+    return { payload: Binary.fromArrayBuffer(decrypted) };
+  } catch (err) {
+    if (err.name === 'OperationError') {
+      throw new TdfDecryptError(err);
+    }
+
+    throw err;
+  }
 }
 
 function _importKey(key: Binary, algorithm: AesCbcParams | AesGcmParams) {