2021-05-28 17:19:31 +02:00

270 lines
9.4 KiB
Markdown

# Bytenode
A minimalist bytecode compiler for Node.js.
This tool truly compiles your JavaScript code into `V8` bytecode, so that you can protect your source code. It can be used with Node.js, as well as Electron and NW.js (check `examples/` directory).
---
## Install
```console
npm install --save bytenode
```
Or globally:
```console
sudo npm install -g bytenode
```
---
## Known Issues and Limitations
* In Node 10.x, Bytenode does not work in debug mode. See [#29](https://github.com/OsamaAbbas/bytenode/issues/29).
* Any code depends on `Function.prototype.toString` function will break, because Bytenode removes the source code from `.jsc` files and puts a dummy code instead. See [#34](https://github.com/OsamaAbbas/bytenode/issues/34).
* In recent versions of Node, the `--no-flush-bytecode` must be set. Bytenode sets it internally, but if you encounter any issues, try to run Node with that flag: ` $ node --no-flush-bytecode server.js`. See [#41](https://github.com/OsamaAbbas/bytenode/issues/41).
* Arrow functions (especially Async arrow functions) cause crash in Puppeteer and in Electron apps if used in render processes. See [#106](https://github.com/bytenode/bytenode/issues/106), [#47](https://github.com/OsamaAbbas/bytenode/issues/47). They also cause an issue with the ndb debugger. See [#135](https://github.com/bytenode/bytenode/issues/135). Use the usual async functions instead.
---
## Bytenode CLI
```
Usage: bytenode [option] [ FILE... | - ] [arguments]
Options:
-h, --help show help information.
-v, --version show bytenode version.
-c, --compile [ FILE... | - ] compile stdin, a file, or a list of files
-n, --no-module compile without producing commonjs module
-e, --electron compile for Electron
-l, --loader [ FILE | PATTERN ] create a loader file and optionally define
loader filename or pattern using % as filename replacer
defaults to %.loader.js
Examples:
$ bytenode -c script.js compile `script.js` to `script.jsc`.
$ bytenode -c server.js app.js
$ bytenode -c src/*.js compile all `.js` files in `src/` directory.
$ bytenode -c *.js -l %.load.js create `filename.load.js` loader files along side `.jsc` files
$ bytenode script.jsc [arguments] run `script.jsc` with arguments.
$ bytenode open Node REPL with bytenode pre-loaded.
```
Examples:
* Compile `express-server.js` to `express-server.jsc`.
```console
user@machine:~$ bytenode --compile express-server.js
```
* Run your compiled file `express-server.jsc`.
```console
user@machine:~$ bytenode express-server.jsc
Server listening on port 3000
```
* Compile all `.js` files in `./app` directory.
```console
user@machine:~$ bytenode --compile ./app/*.js
```
* Compile all `.js` files in your project.
```console
user@machine:~$ bytenode --compile ./**/*.js
```
Note: you may need to enable `globstar` option in bash (you should add it to `~/.bashrc`):
`shopt -s globstar`
* Starting from v1.0.0, bytenode can compile from `stdin`.
```console
$ echo 'console.log("Hello");' | bytenode --compile - > hello.jsc
```
---
## Bytenode API
```javascript
const bytenode = require('bytenode');
```
---
#### bytenode.compileCode(javascriptCode) → {Buffer}
Generates v8 bytecode buffer.
- Parameters:
| Name | Type | Description |
| ---- | ---- | ----------- |
| javascriptCode | string | JavaScript source that will be compiled to bytecode. |
- Returns:
{Buffer} The generated bytecode.
- Example:
```javascript
let helloWorldBytecode = bytenode.compileCode(`console.log('Hello World!');`);
```
This `helloWorldBytecode` bytecode can be saved to a file. However, if you want to use your code as a module (i.e. if your file has some `exports`), you have to compile it using `bytenode.compileFile({compileAsModule: true})`, or wrap your code manually, using `Module.wrap()` function.
---
#### bytenode.compileElectronCode(javascriptCode) → {Promise\<Buffer\>}
Asynchronous function which generates v8 bytecode buffer for Electron.
Same as `bytenode.compileCode()`, but generates bytecode for the version of Electron currently installed in node_modules.
- Parameters:
| Name | Type | Description |
| ---- | ---- | ----------- |
| javascriptCode | string | JavaScript source that will be compiled to bytecode. |
- Returns:
{Promise\<Buffer\>} A Promise which resolves with the generated bytecode.
- Example:
```javascript
let helloWorldBytecode = await bytenode.compileElectronCode(`console.log('Hello World!');`);
```
This `helloWorldBytecode` bytecode can be saved to a file. However, if you want to use your code as a module (i.e. if your file has some `exports`), you have to compile it using `bytenode.compileFile({compileAsModule: true})`, or wrap your code manually, using `Module.wrap()` function.
---
#### bytenode.runBytecode(bytecodeBuffer) → {any}
Runs v8 bytecode buffer and returns the result.
- Parameters:
| Name | Type | Description |
| ---- | ---- | ----------- |
| bytecodeBuffer | Buffer | The buffer object that was created using compileCode function. |
- Returns:
{any} The result of the very last statement executed in the script.
- Example:
```javascript
bytenode.runBytecode(helloWorldBytecode);
// prints: Hello World!
```
---
#### bytenode.compileFile(args, output) → {Promise\<string\>}
Asyncrhonous function which compiles JavaScript file to .jsc file.
- Parameters:
| Name | Type | Description |
| ---- | ---- | ----------- |
| args | object \| string | |
| args.filename | string | The JavaScript source file that will be compiled. |
| args.compileAsModule | boolean | If true, the output will be a commonjs module. Default: true. |
| args.electron | boolean | If true, the output will be a compiled through Electrong. Default: false. |
| args.output | string | The output filename. Defaults to the same path and name of the original file, but with `.jsc` extension. |
| output | string | The output filename. (Deprecated: use args.output instead) |
- Returns:
{Promise\<string\>}: A Promise that resolves as the compiled filename.
- Examples:
```javascript
let compiledFilename = bytenode.compileFile({
filename: '/path/to/your/file.js',
output: '/path/to/compiled/file.jsc' // if omitted, it defaults to '/path/to/your/file.jsc'
});
```
Previous code will produce a commonjs module that can be required using `require` function.
```javascript
let compiledFilename = await bytenode.compileFile({
filename: '/path/to/your/file.js',
output: '/path/to/compiled/file.jsc',
compileAsModule: false
});
```
Previous code will produce a direct `.jsc` file, that can be run using `bytenode.runBytecodeFile()` function. It can NOT be required as a module. Please note that `compileAsModule` MUST be `false` in order to turn it off. Any other values (including: `null`, `""`, etc) will be treated as `true`. (It had to be done this way in order to keep the old code valid.)
---
#### bytenode.runBytecodeFile(filename) → {any}
Runs .jsc file and returns the result.
- Parameters:
| Name | Type |
| ---- | ---- |
| filename | string |
- Returns:
{any} The result of the very last statement executed in the script.
- Example:
```javascript
// test.js
console.log('Hello World!');
```
```javascript
bytenode.runBytecodeFile('/path/to/test.jsc');
// prints: Hello World!
```
---
#### require(filename) → {any}
- Parameters:
| Name | Type |
| ---- | ---- |
| filename | string |
- Returns:
{any} exported module content
- Example:
```javascript
let myModule = require('/path/to/your/file.jsc');
```
Just like regular `.js` modules. You can also omit the extension `.jsc`.
`.jsc` file must have been compiled using `bytenode.compileFile()`, or have been wrapped inside `Module.wrap()` function. Otherwise it won't work as a module and it can NOT be required.
Please note `.jsc` files must run with the same Node.js version that was used to compile it (using same architecture of course). Also, `.jsc` files are CPU-agnostic. However, you should run your tests before and after deployment, because V8 sanity checks include some checks related to CPU supported features, so this may cause errors in some rare cases.
---
## Acknowledgements
I had the idea of this tool many years ago. However, I finally decided to implement it after seeing this [issue](https://github.com/nodejs/node/issues/11842) by @hashseed. Also, some parts were inspired by [v8-compile-cache](https://github.com/zertosh/v8-compile-cache) by @zertosh.