How do I call a Javascript function from Python?

Question

I am working on a web-scraping project. One of the websites I am working with has the data coming from Javascript.

There was a suggestion on one of my earlier questi

Answer 1

An interesting alternative I discovered recently is the Python bond module, which can be used to communicate with a NodeJs process (v8 engine).

Usage would be very similar to the pyv8 bindings, but you can directly use any NodeJs library without modification, which is a major selling point for me.

Your python code would look like this:

val = js.call('add2', var1, var2)

or even:

add2 = js.callable('add2')
val = add2(var1, var2)

Calling functions though is definitely slower than pyv8, so it greatly depends on your needs. If you need to use an npm package that does a lot of heavy-lifting, bond is great. You can even have more nodejs processes running in parallel.

But if you just need to call a bunch of JS functions (for instance, to have the same validation functions between the browser/backend), pyv8 will definitely be a lot faster.