Duktape Javascript Virtual Machine
This project is a thin wrapper around the Duktape Embedded Javascript Engine compiled to webassembly/asmjs.
- Airtight sandbox for unsafe js code.
- Runs in modern web browsers using Webassembly with asmjs fallback.
- Runs on anything that supports NodeJS (no native code/compilation!).
- Restricted code (cannot access node.js or window methods).
- VM supports ES5 and earlier javascript.
- Supports bidirectional messaging.
- Only 110KB gzipped.
2 minute example
const obj = {
key: "value";
}
const vm = await DuktapeVM(`
// Provide data and methods to VM instance
// vm_breakout() allows you to eval code in the parent window/global space.
// vm_breakout is only available here, it's not available in subsequent "vm.eval" calls.
exports.console = function(message) {
// print to parent console
vm_breakout("console.log('" + message + "');")
};
exports.someObj = ${JSON.stringify(obj)};
// you can also inline js libraries here
`);
vm.eval("2 + 2")
vm.eval("exports.console('hello, world!')")
vm.eval("exports.someObj.key")
vm.eval(`
exports.onMessage(function(msg) {
// got message from parent!
})
// send message to parent
exports.message("some message to parent");
`);
vm.message("this is a message to the vm");
vm.onMessage((msg) => {
console.log("Got message from vm: " + msg);
})
vm.destroy();
Installation
npm i duktape-vm --save
Using in Typescript/Babel project:
import { DuktapeVM } from "duktape-vm";
Using in Node:
const DuktapeVM = require("duktape-vm").DuktapeVM;
To use directly in the browser, drop ONE of the tags below into your <head>
.
<script src="https://cdn.jsdelivr.net/npm/duktape-vm@0.0.3/build/duktape-vm.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/duktape-vm@0.0.3/build/duktape-vm.min.asm.js"></script>
<script src="https://cdn.jsdelivr.net/npm/duktape-vm@0.0.3/build/duktape-vm.min.both.js"></script>
MIT License
Copyright (c) 2018 Scott Lott
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.