I have a question that has been asked several times here and other places around the internet*, but answers I've seen are inplete or ineffective.

I would like to have a JavaScript function runPy() that, upon being called (in a browser, via a button-click for instance), will execute a Python script in my server that we'll call test.py.

Let's say that test.py is simply designed to create a text file and write in it 'hello world'

Python

f = open('test.txt', 'w+')
f.write('hello world')

Based on other answers, I have pieced together the following JavaScript/jQuery function:

JavaScript

function runPy() {
    $.ajax({
        type:'POST',
        url:'test.py',
        success: function(data) {                                                     
            console.log(data)
        };
    });
}

Now, this is of course incorrect. As one might expect, rather than running the Python script, it prints to the console the contents of the script:

Console

f = open('test.txt', 'w+')
f.write('hello world')

How would I go about editing my JavaScript (and/or Python) to achieve the functionality I would like? In a perfect world, I would like to avoid importing any new dependencies (I've seen some answers dependent on Flask or Django) but of course beggars can't be choosers.

Additionally, if I will allow myself to get greedy, it would be very nice to be able to pass arguments to the Python script as well, or even use JavaScript to call a specific function in the Python script, and have the results passed back to the client-side JavaScript.

*Similar Questions
Call python function from JS
how to call python script from javascript?
Run Python scripts from JavaScript functions

I have a question that has been asked several times here and other places around the internet*, but answers I've seen are inplete or ineffective.

I would like to have a JavaScript function runPy() that, upon being called (in a browser, via a button-click for instance), will execute a Python script in my server that we'll call test.py.

Let's say that test.py is simply designed to create a text file and write in it 'hello world'

Python

f = open('test.txt', 'w+')
f.write('hello world')

Based on other answers, I have pieced together the following JavaScript/jQuery function:

JavaScript

function runPy() {
    $.ajax({
        type:'POST',
        url:'test.py',
        success: function(data) {                                                     
            console.log(data)
        };
    });
}

Now, this is of course incorrect. As one might expect, rather than running the Python script, it prints to the console the contents of the script:

Console

f = open('test.txt', 'w+')
f.write('hello world')

How would I go about editing my JavaScript (and/or Python) to achieve the functionality I would like? In a perfect world, I would like to avoid importing any new dependencies (I've seen some answers dependent on Flask or Django) but of course beggars can't be choosers.

Additionally, if I will allow myself to get greedy, it would be very nice to be able to pass arguments to the Python script as well, or even use JavaScript to call a specific function in the Python script, and have the results passed back to the client-side JavaScript.

*Similar Questions
Call python function from JS
how to call python script from javascript?
Run Python scripts from JavaScript functions

• javascript
• python
• ajax

• Youre probably not finding good answers because you are using the wrong search terms. If I understand it correctly you want to execute a python script serverside when the web server receives a specific request. This needs to be configured serverside, either through cgi, or by having your server side logic execute the python script for certain routes. – visibleman Commented May 25, 2020 at 4:34
• You can use the built-in http.server. you make a request to the http server instead of accessing the python file directly. you can execute any python code inside the server based on the request URL. you can send back the data with a print statement. yes, you can even pass arguments as http query strings or post data. using a library like Flask makes it way easier. – Himal Commented May 25, 2020 at 4:54

1 Answer 1

You're going on the right path.

But, here's why the POST isn't working. Except for HTML filetype, making a POST call to fetch a static file on the server (i.e. random.js, random.css etc) will print the raw file content. In this scenario, you'll need to handle this on the server-side backend code. I don't know which backend framework you're using but here are some articles that can help you with this:

NodeJS: https://medium./swlh/run-python-script-from-node-js-and-send-data-to-browser-15677fcf199f

.NET: https://medium./better-programming/running-python-script-from-c-and-working-with-the-results-843e68d230e5

Java: Running a .py file from Java

UPDATE!!: Due to the recent developments in the space of Web Development, it is now possible to run Python on the Client-side through WebAssembly. Please find more instructions here: Pyodide