From 0455923e439974b6de848754332d05ebe4b2d3c1 Mon Sep 17 00:00:00 2001
From: Jerome Wu <jeromewus@gmail.com>
Date: Wed, 30 Oct 2019 21:23:51 +0800
Subject: [PATCH] Fix worker cross domain issue

---
 README.md                            |  4 ++++
 src/createWorker.js                  |  5 +++--
 src/utils/getEnvironment.js          | 10 ++++++++++
 src/utils/resolvePaths.js            | 12 ++++++++++++
 src/worker/browser/defaultOptions.js |  1 +
 src/worker/browser/spawnWorker.js    | 16 +++++++++++++---
 6 files changed, 43 insertions(+), 5 deletions(-)
 create mode 100644 src/utils/getEnvironment.js
 create mode 100644 src/utils/resolvePaths.js

diff --git a/README.md b/README.md
index b52d72b..b8143e7 100644
--- a/README.md
+++ b/README.md
@@ -22,6 +22,10 @@ Use FFmpeg directly in your browser without any backend services!!
   </a>
 </p>
 
+<a href="https://codepen.io/jeromewu/pen/NWWaMeY" target="_blank">
+<img alt="codepen" width="128px" src="https://blog.codepen.io/wp-content/uploads/2012/06/codepen-wordmark-display-inside-black@10x.png">
+</a>
+
 [Source Code](https://github.com/ffmpegjs/ffmpeg.js/blob/master/examples/browser/transcode.html)
 
 ---
diff --git a/src/createWorker.js b/src/createWorker.js
index a8469e1..8a4829b 100644
--- a/src/createWorker.js
+++ b/src/createWorker.js
@@ -1,6 +1,7 @@
 const createJob = require('./createJob');
 const { log } = require('./utils/log');
 const getId = require('./utils/getId');
+const resolvePaths = require('./utils/resolvePaths');
 const {
   defaultOptions,
   spawnWorker,
@@ -17,10 +18,10 @@ module.exports = (_options = {}) => {
   const {
     logger,
     ...options
-  } = {
+  } = resolvePaths({
     ...defaultOptions,
     ..._options,
-  };
+  });
   const resolves = {};
   const rejects = {};
   let worker = spawnWorker(options);
diff --git a/src/utils/getEnvironment.js b/src/utils/getEnvironment.js
new file mode 100644
index 0000000..71b1c01
--- /dev/null
+++ b/src/utils/getEnvironment.js
@@ -0,0 +1,10 @@
+module.exports = (key) => {
+  const env = {
+    type: (typeof window !== 'undefined') && (typeof window.document !== 'undefined') ? 'browser' : 'node',
+  };
+
+  if (typeof key === 'undefined') {
+    return env;
+  }
+  return env[key];
+};
diff --git a/src/utils/resolvePaths.js b/src/utils/resolvePaths.js
new file mode 100644
index 0000000..93be72f
--- /dev/null
+++ b/src/utils/resolvePaths.js
@@ -0,0 +1,12 @@
+const isBrowser = require('./getEnvironment')('type') === 'browser';
+const resolveURL = isBrowser ? require('resolve-url') : s => s; // eslint-disable-line
+
+module.exports = (options) => {
+  const opts = { ...options };
+  ['corePath', 'workerPath'].forEach((key) => {
+    if (typeof options[key] !== 'undefined') {
+      opts[key] = resolveURL(opts[key]);
+    }
+  });
+  return opts;
+};
diff --git a/src/worker/browser/defaultOptions.js b/src/worker/browser/defaultOptions.js
index 55146c0..61bd237 100644
--- a/src/worker/browser/defaultOptions.js
+++ b/src/worker/browser/defaultOptions.js
@@ -11,4 +11,5 @@ module.exports = {
     ? resolveURL(`/dist/worker.dev.js?nocache=${Math.random().toString(36).slice(3)}`)
     : `https://unpkg.com/@ffmpeg/ffmpeg@v${version}/dist/worker.min.js`,
   corePath: `https://unpkg.com/@ffmpeg/core@v${dependencies['@ffmpeg/core'].substring(1)}/ffmpeg-core.js`,
+  workerBlobURL: true,
 };
diff --git a/src/worker/browser/spawnWorker.js b/src/worker/browser/spawnWorker.js
index 5604aa4..4344f8a 100644
--- a/src/worker/browser/spawnWorker.js
+++ b/src/worker/browser/spawnWorker.js
@@ -5,6 +5,16 @@
  * @function create a new Worker in browser
  * @access public
  */
-module.exports = ({ workerPath }) => (
-  new Worker(workerPath)
-);
+module.exports = ({ workerPath, workerBlobURL }) => {
+  let worker;
+  if (Blob && URL && workerBlobURL) {
+    /* Use Blob to load cross domain worker script */
+    const blob = new Blob([`importScripts("${workerPath}");`], {
+      type: 'application/javascript',
+    });
+    worker = new Worker(URL.createObjectURL(blob));
+  } else {
+    worker = new Worker(workerPath);
+  }
+  return worker;
+};