PhpExecJs

PhpExecJS lets you run JavaScript code from PHP.

Short example:

print_r($phpexecjs->evalJs("'red yellow blue'.split(' ')"));

Will print:

Array
(
    [0] => red
    [1] => yellow
    [2] => blue
)

Installation

composer require nacmartin/phpexecjs

Sample program

Usage

<?php
    require __DIR__ . '/../vendor/autoload.php';
    
    use Nacmartin\PhpExecJs\PhpExecJs;
    
    $phpexecjs = new PhpExecJs();
    
    print_r($phpexecjs->evalJs("'red yellow blue'.split(' ')"));

Will print:

Array
(
    [0] => red
    [1] => yellow
    [2] => blue
)

Using contexts

You can set up a context, like libraries and whatnot, that you want to use in your eval'd code. This is used for instance by the ReactBundle to render React server-side.

For instance, we can compile CoffeeScript using this feature:

    $phpexecjs->createContextFromFile("http://coffeescript.org/extras/coffee-script.js");
    print_r($phpexecjs->call("CoffeeScript.compile", ["square = (x) -> x * x", ['bare' => true]]));


That will print:

      var square;
    
      square = function(x) {
        return x * x;
      };

You can extend this example to do things like use this function as context:

    $square = $phpexecjs->call("CoffeeScript.compile", ["square = (x) -> x * x", ['bare' => true]]);
    $phpexecjs->createContext($square);
    print_r($phpexecjs->evalJs('square(3)'));

That will print 9.

This can be used for instance, to use CoffeeScript or compile templates in JavaScript templating languages.

How it works

When you run evalJs, the code will be inserted into a small wrapper used to run JavaScript's eval() against your code and check the status for error handling.

If you set up a context, the code will be inserted before the call to eval() in JavaScript, and if you have the V8Js extension installed, it will precompile it.

Runtimes supported

By default, PhPExecjs will auto-detect the best runtime available. Currently, the routines supported are:

• V8Js (PHP extension)
• node.js

It is recommended to have V8Js installed, but you may want to have it installed in production and still be able to use PhpExecJs calling node as a subprocess during development, so you don't need to install the extension.

Adding a external runtime

If you have a external runner (let's say, Spidermonkey), and you want to use it, pass it to the constructor:

    $myRuntime = new ExternalRuntime('My runtime name', 'my_command');
    $phpExecJs = new PhpExecJs($myRuntime);

Contributing with runtimes

We would like to support more runtimes (Duktape, for instance). If you want to contribute with a runtime, it is pretty simple. You just have to implement src/Runtimes/RuntimeInterface. Check the directory src/Runtimes for examples.

Why can't I use some functions like setTimeout?

PhpExecJs provides a common denominator interface to JavaScript runtimes, so it can only run code that is agnostic about the interpreter. Thus, some features are disabled. Notably, timer functions are disabled because not all runtimes guarantee a full JavaScript event loop. If you want to use any of these please use directly node.js instead of this higher level library:

global, module, exports, require, console, setTimeout, setInterval, clearTimeout, clearInterval, setImmediate, clearImmediate

Credits

This library is inspired in ExecJs, A Ruby library.

The code used to manage processes and temporary files has been adapted from the Snappy library by KNP Labs.