true-pasky / PyExecJS

Run JavaScript code from Python

PyExecJS

Run JavaScript code from Python.

PyExecJS is a porting of ExecJS from Ruby. PyExecJS automatically picks the best runtime available to evaluate your JavaScript program, then returns the result to you as a Python object.

A short example:

>>> import execjs
>>> execjs.eval("'red yellow blue'.split(' ')")
['red', 'yellow', 'blue']
>>> ctx = execjs.compile("""
...     function add(x, y) {
...         return x + y;
...     }
... """)
>>> ctx.call("add", 1, 2)
3

Of course, you can pick particular JavaScript runtime by get() function:

>>> default = execjs.get() # the automatically picked runtime
>>> default.eval("1 + 2")
3
>>> jscript = execjs.get("JScript")
>>> jscript.eval("1 + 2")
3
>>> node = execjs.get("Node")
>>> node.eval("1 + 2")
3

If EXECJS_RUNTIME environment variable is specified, PyExecJS pick the JavaScript runtime as a default:

>>> #execjs.get().name # this value is depends on your environment.
>>> os.environ["EXECJS_RUNTIME"] = "Node"
>>> execjs.get().name
'Node.js (V8)'

PyExecJS supports these runtimes:

• PyV8 - A python wrapper for Google V8 engine,
• Node.js
• Apple JavaScriptCore - Included with Mac OS X
• Mozilla SpiderMonkey
• Microsoft Windows Script Host (JScript)

Installation

$ pip install PyExecJS

or

$ easy_install PyExecJS

License

Copyright (c) 2012 Omoto Kenji. Copyright (c) 2011 Sam Stephenson and Josh Peek.

Released under the MIT license. See LICENSE for details.

Changes

1.0.5

• Supported Python 3.3
• Fixed file handle leaking
• Fixed issue with passenger-nginx-4.0

1.0.4

• Removed "import execjs" (it prevent execution of setup.py by Python 2.6)

1.0.3

• Javascript sources were embeded in init.py. 'which' command were reimplemented by pure python.

1.0.2

• Python 2.6.x was supported.

1.0.1

• Forgotten shell=True was added to Popen.

1.0.0

• First release.