Don't attempt to use workers if they fail to load

README.md

@@ -119,7 +119,7 @@ Here are some examples of how to use the v2.x+ API. For more elaborate examples
 ```js
 var openpgp = require('openpgp'); // use as CommonJS, AMD, ES6 module or via window.openpgp
 
-openpgp.initWorker({ path:'openpgp.worker.js' }) // set the relative web worker path
+await openpgp.initWorker({ path:'openpgp.worker.js' }) // set the relative web worker path
 ```
 
 #### Encrypt and decrypt *Uint8Array* data with a password
@@ -159,7 +159,7 @@ Encryption will use the algorithm preferred by the public key (defaults to aes25
 ```js
 const openpgp = require('openpgp') // use as CommonJS, AMD, ES6 module or via window.openpgp
 
-openpgp.initWorker({ path:'openpgp.worker.js' }) // set the relative web worker path
+await openpgp.initWorker({ path:'openpgp.worker.js' }) // set the relative web worker path
 
 // put keys in backtick (``) to avoid errors caused by spaces or tabs
 const pubkey = `-----BEGIN PGP PUBLIC KEY BLOCK-----

src/openpgp.js

@@ -63,12 +63,19 @@ let asyncProxy; // instance of the asyncproxy
  * @param {String} path            relative path to the worker scripts, default: 'openpgp.worker.js'
  * @param {Number} n               number of workers to initialize
  * @param {Array<Object>} workers  alternative to path parameter: web workers initialized with 'openpgp.worker.js'
+ * @returns {Promise<Boolean>}     returns a promise that resolves to true if all workers have succesfully finished loading
+ * @async
  */
-export function initWorker({ path='openpgp.worker.js', n = 1, workers = [] } = {}) {
+export async function initWorker({ path='openpgp.worker.js', n = 1, workers = [] } = {}) {
   if (workers.length || (typeof window !== 'undefined' && window.Worker && window.MessageChannel)) {
-    asyncProxy = new AsyncProxy({ path, n, workers, config });
-    return true;
+    const proxy = new AsyncProxy({ path, n, workers, config });
+    const loaded = await proxy.loaded();
+    if (loaded) {
+      asyncProxy = proxy;
+      return true;
+    }
   }
+  return false;
 }
 
 /**

src/worker/async_proxy.js

@@ -49,6 +49,9 @@ function AsyncProxy({ path='openpgp.worker.js', n = 1, workers = [], config } =
   const handleMessage = workerId => event => {
     const msg = event.data;
     switch (msg.event) {
+      case 'loaded':
+        this.workers[workerId].loadedResolve(true);
+        break;
       case 'method-return':
         if (msg.err) {
           // fail
@@ -83,10 +86,15 @@ function AsyncProxy({ path='openpgp.worker.js', n = 1, workers = [], config } =
 
   let workerId = 0;
   this.workers.forEach(worker => {
+    worker.loadedPromise = new Promise(resolve => {
+      worker.loadedResolve = resolve;
+    });
     worker.requests = 0;
     worker.onmessage = handleMessage(workerId++);
     worker.onerror = e => {
-      throw new Error('Unhandled error in openpgp worker: ' + e.message + ' (' + e.filename + ':' + e.lineno + ')');
+      worker.loadedResolve(false);
+      console.error('Unhandled error in openpgp worker: ' + e.message + ' (' + e.filename + ':' + e.lineno + ')');
+      return false;
     };
 
     if (config) {
@@ -99,6 +107,15 @@ function AsyncProxy({ path='openpgp.worker.js', n = 1, workers = [], config } =
   this.currentID = 0;
 }
 
+/**
+ * Returns a promise that resolves when all workers have finished loading
+ * @returns {Promise<Boolean>} Resolves to true if all workers have loaded succesfully; false otherwise
+*/
+AsyncProxy.prototype.loaded = async function() {
+  const loaded = await Promise.all(this.workers.map(worker => worker.loadedPromise));
+  return loaded.every(Boolean);
+};
+
 /**
  * Get new request ID
  * @returns {integer}          New unique request ID

src/worker/worker.js

@@ -135,3 +135,8 @@ function delegate(id, method, options) {
 function response(event) {
   self.postMessage(event, openpgp.util.getTransferables(event.data, true));
 }
+
+/**
+ * Let the main window know the worker has loaded.
+ */
+postMessage({ event: 'loaded' });

test/general/brainpool.js

@@ -273,8 +273,8 @@ describe('Brainpool Cryptography', function () {
 
   tryTests('Brainpool Worker Tests', omnibus, {
     if: typeof window !== 'undefined' && window.Worker,
-    before: function() {
-      openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
+    before: async function() {
+      await openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
     },
     beforeEach: function() {
       openpgp.config.use_native = true;

test/general/ecc_nist.js

@@ -297,8 +297,8 @@ describe('Elliptic Curve Cryptography', function () {
 
   tryTests('ECC Worker Tests', omnibus, {
     if: typeof window !== 'undefined' && window.Worker,
-    before: function() {
-      openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
+    before: async function() {
+      await openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
     },
     beforeEach: function() {
       openpgp.config.use_native = true;

test/general/openpgp.js

@@ -444,13 +444,16 @@ describe('[Sauce Labs Group 2] OpenPGP.js public api tests', function() {
       openpgp.destroyWorker(); // cleanup worker in case of failure
     });
 
-    it('should work', function() {
+    it('should work', async function() {
       const workerStub = {
         postMessage: function() {}
       };
-      openpgp.initWorker({
-        workers: [workerStub]
-      });
+      await Promise.all([
+        openpgp.initWorker({
+          workers: [workerStub]
+        }),
+        workerStub.onmessage({ data: { event: 'loaded' } })
+      ]);
       expect(openpgp.getWorker()).to.exist;
       openpgp.destroyWorker();
       expect(openpgp.getWorker()).to.not.exist;
@@ -595,13 +598,16 @@ describe('[Sauce Labs Group 2] OpenPGP.js public api tests', function() {
       });
     });
 
-    it('should delegate to async proxy', function() {
+    it('should delegate to async proxy', async function() {
       const workerStub = {
         postMessage: function() {}
       };
-      openpgp.initWorker({
-        workers: [workerStub]
-      });
+      await Promise.all([
+        openpgp.initWorker({
+          workers: [workerStub]
+        }),
+        workerStub.onmessage({ data: { event: 'loaded' } })
+      ]);
       const proxyGenStub = stub(openpgp.getWorker(), 'delegate');
       getWebCryptoAllStub.returns();
 
@@ -643,9 +649,9 @@ describe('[Sauce Labs Group 2] OpenPGP.js public api tests', function() {
       });
     });
 
-    it('should work in JS (with worker)', function() {
+    it('should work in JS (with worker)', async function() {
       openpgp.config.use_native = false;
-      openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
+      await openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
       const opt = {
         userIds: [{ name: 'Test User', email: 'text@example.com' }],
         numBits: 512
@@ -727,11 +733,11 @@ describe('[Sauce Labs Group 2] OpenPGP.js public api tests', function() {
       openpgp.config.aead_chunk_size_byte = aead_chunk_size_byteVal;
     });
 
-    it('Configuration', function() {
+    it('Configuration', async function() {
       openpgp.config.show_version = false;
       openpgp.config.commentstring = 'different';
       if (openpgp.getWorker()) { // init again to trigger config event
-        openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
+        await openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
       }
       return openpgp.encrypt({ publicKeys:publicKey.keys, message:openpgp.message.fromText(plaintext) }).then(function(encrypted) {
         expect(encrypted.data).to.exist;
@@ -749,7 +755,7 @@ describe('[Sauce Labs Group 2] OpenPGP.js public api tests', function() {
       const { workers } = openpgp.getWorker();
       try {
         await privateKey.keys[0].decrypt(passphrase)
-        openpgp.initWorker({path: '../dist/openpgp.worker.js', workers, n: 2});
+        await openpgp.initWorker({path: '../dist/openpgp.worker.js', workers, n: 2});
 
         const workerTest = (_, index) => {
           const plaintext = input.createSomeMessage() + index;
@@ -770,7 +776,7 @@ describe('[Sauce Labs Group 2] OpenPGP.js public api tests', function() {
         };
         await Promise.all(Array(10).fill(null).map(workerTest));
       } finally {
-        openpgp.initWorker({path: '../dist/openpgp.worker.js', workers, n: 1 });
+        await openpgp.initWorker({path: '../dist/openpgp.worker.js', workers, n: 1 });
       }
     });
 
@@ -828,8 +834,8 @@ describe('[Sauce Labs Group 2] OpenPGP.js public api tests', function() {
 
     tryTests('CFB mode (asm.js, worker)', tests, {
       if: typeof window !== 'undefined' && window.Worker,
-      before: function() {
-        openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
+      before: async function() {
+        await openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
       },
       beforeEach: function() {
         openpgp.config.aead_protect = false;

test/general/x25519.js

@@ -319,8 +319,8 @@ describe('X25519 Cryptography', function () {
 
   tryTests('X25519 Worker Tests', omnibus, {
     if: typeof window !== 'undefined' && window.Worker,
-    before: function() {
-      openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
+    before: async function() {
+      await openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
     },
     beforeEach: function() {
       openpgp.config.use_native = true;

test/worker/async_proxy.js

@@ -37,7 +37,7 @@ let pubKey;
 tryTests('Async Proxy', tests, {
   if: typeof window !== 'undefined' && window.Worker && window.MessageChannel,
   before: async function() {
-    openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
+    await openpgp.initWorker({ path:'../dist/openpgp.worker.js' });
     pubKey = (await openpgp.key.readArmored(pub_key)).keys[0];
   },
   after: function() {
@@ -48,11 +48,13 @@ tryTests('Async Proxy', tests, {
 function tests() {
 
   describe('Random number pipeline', function() {
-    it('Random number buffer automatically reseeded', function() {
+    it('Random number buffer automatically reseeded', async function() {
       const worker = new Worker('../dist/openpgp.worker.js');
       const wProxy = new openpgp.AsyncProxy({ path:'../dist/openpgp.worker.js', workers: [worker] });
-
-      return wProxy.delegate('encrypt', { publicKeys:[pubKey], message:openpgp.message.fromText(plaintext) });
+      const loaded = await wProxy.loaded();
+      if (loaded) {
+        return wProxy.delegate('encrypt', { publicKeys:[pubKey], message:openpgp.message.fromText(plaintext) });
+      }
     });
   });