Package: pyduktape2
IntroductionPyduktape is a python wrapper aroundDuktape,
an embeddable Javascript interpreter.On top of the interpreter wrapper, pyduktape offers easy integration
between the Python and the Javascript environments. You can pass
Python objects to Javascript, call methods on them and access their
attributes.  Similarly, you can pass Javascript objects to Python.Objects are never copied or serialized. Instead, they are passed
between the two environments using proxy objects. Proxy objects
delegate the execution to the original object environment.ThreadingIt is possible to invoke Javascript code from multiple threads. Each
thread will need to use its own embedded interpreter. Javascript
objects returned to the Python environment will only be usable on the
same thread that created them. The runtime always checks this
condition automatically, and raises aDuktapeThreadErrorif it’s
violated.Getting StartedInstallationTo install from pypi:$ pip install pyduktape2To install the latest version from github:$ pip install git+https://github.com/phith0n/pyduktape2Running Javascript codeTo run Javascript code, you need to create an execution context and
use the methodeval_js:import pyduktape2

context = pyduktape2.DuktapeContext()
context.eval_js("print(Duktape.version);")Each execution context starts its own interpreter. Each context is
independent, and tied to the Python thread that created it. Memory is
automatically managed.To evaluate external Javascript files, useeval_js_file:// helloWorld.js
print('Hello, World!');

# in the Python interpreter
import pyduktape2

context = pyduktape2.DuktapeContext()
context.eval_js_file('helloWorld.js')Pyduktape supports Javascript modules:// js/helloWorld.js
exports.sayHello = function () {
    print('Hello, World!');
};

// js/main.js
var helloWorld = require('js/helloWorld');
helloWorld.sayHello();

# in the Python interpreter
import pyduktape2

context = pyduktape2.DuktapeContext()
context.eval_js_file('js/main')The.jsextension is automatically added if missing.  Relative
paths are relative to the current working directory, but you can
change the base path usingset_base_path:# js/helloWorld.js
print('Hello, World!');

# in the Python interpreter
import pyduktape2

context = pyduktape2.DuktapeContext()
context.set_base_path('js')
context.eval_js_file('helloWorld')Python and Javascript integrationYou can useset_globalsto set Javascript global variables:import pyduktape2

def say_hello(to):
    print 'Hello, {}!'.format(to)

context = pyduktape2.DuktapeContext()
context.set_globals(sayHello=say_hello, world='World')
context.eval_js("sayHello(world);")You can useget_globalto access Javascript global variables:import pyduktape2

context = pyduktape2.DuktapeContext()
context.eval_js("var helloWorld = 'Hello, World!';")
print context.get_global('helloWorld')eval_jsreturns the value of the last expression:import pyduktape2

context = pyduktape2.DuktapeContext()
hello_world = context.eval_js("var helloWorld = 'Hello, World!'; helloWorld")
print hello_worldYou can seamlessly use Python objects and functions within Javascript
code.  There are some limitations, though: any Python callable can
only be used as a function, and other attributes cannot be
accessed. Primitive types (int, float, string, None) are converted to
equivalent Javascript primitives.  The following code shows how to
interact with a Python object from Javascript:import pyduktape2

class Hello(object):
    def __init__(self, what):
        self.what = what

    def say(self):
        print('Hello, {}!'.format(self.what))

context = pyduktape2.DuktapeContext()
context.set_globals(Hello=Hello)
context.eval_js("var helloWorld = Hello('World'); helloWorld.say();")In the same way, you can use Javascript objects in Python.  You can
use the special methodnewto instantiate an object:import pyduktape2

context = pyduktape2.DuktapeContext()
Hello = context.eval_js("""
function Hello(what) {
    this.what = what;
}

Hello.prototype.say = function () {
    print('Hello, ' + this.what + '!');
};

Hello
""")

hello_world = Hello.new('World')
hello_world.say()You can use Python lists and dicts from Javascript, and viceversa:import pyduktape2

context = pyduktape2.DuktapeContext()
res = context.eval_js('[1, 2, 3]')

for item in res:
    print(item)

context.set_globals(lst=[4, 5, 6])
context.eval_js('for (var i = 0; i < lst.length; i++) { print(lst[i]); }')

res = context.eval_js('var x = {a: 1, b: 2}; x')
for key, val in res.items():
    print(key, '=', val)
res.c = 3
context.eval_js('print(x.c);')

context.set_globals(x=dict(a=1, b=2))
context.eval_js("""
var items = x.items();
for (var i = 0; i < items.length; i++) {
    print(items[i][0] + ' = ' + items[i][1]);
}
""")
context.set_globals(x=dict(a=1, b=2))
context.eval_js('for (var k in x) { print(k + ' = ' + x[k]); }')