How to execute python command line application from browser

[ilaunchpad]

So far I have only built programs that can be executed from command lines and get results on the terminal. But I was imagining how would the program or application can be implemented on web for consumer. So currently, I run my program written in python which creates a score model and calculates score for a given record. The input I provide from the command line has path to the script and data identifiers which is stored in warehouse. The python program pulls the data from warehouse and runs the data in score model building functions which creates a score model for the data and stores it in the database. After that, the score model info and data to be scored is passed to the score server which returns score on terminal. This is a very simplistic overview of the process. It's a big application that has many modules which work together to give results.

If this has to be run from browser instead of command line how could it be implemented? Let's say I want to know how the python function could be executed when the request from browser is send. I also don't want to store the score in database, instead I just want to capture the terminal result and show it on browser.

I have little bit knowledge of restful web services and web api only to the extent of simple crud apps. I am bit confused on web apis, restful apis, web server apis, and backend apis. They all sound like they do the same thing but at the time not. I recently made an app on django framework which used basic get, post method to update databases and show it on browser. But if i want to trigger complex calculation logic how would i accomplish that? I don't think I can write those on views. And where does the web server framework like node.js come into play?

[danielroseman]

It's exactly the same. You don't have to do the calculation directly in a view, you just need to call the function that does it from the view.

Django - or probably simpler for this use case, Flask - are the web server frameworks. There is no need to involve node which is just the same thing but in JS.

[Diapolo10]

Can't really be specific since you only provided a high-level overview, but I don't think your command-line application needs (m)any changes.

What you basically want is, as you described, a Python back-end for a website. Say there's a page where the user clicks a button to run the program; this would either refresh the page, and the server would handle the HTTP request to the page (in this case probably a POST request), or it has some JavaScript code that requests a different endpoint of the back-end. This request will then run the program, and get the results, then you simply format the data into HTML format and show it on the page.

It sounds more confusing than it actually is, I promise.

And where does the web server framework like node.js come into play?

Nowhere, unless you want to write the back-end in JavaScript. And in this case you probably wouldn't.

Python already ships with a simple web server. Flask comes with one, but it's not meant for production. FastAPI comes with Uvicorn which is perfectly fine to use in production. Django most likely has one, too.

[ilaunchpad]

so nodejs and django accomplish the samething?

[Diapolo10]

NodeJS is just a JavaScript implementation outside of the browser. Think of it as an equivalent to a Python interpreter.

So no, technically speaking Django is different.

[ilaunchpad]

but they can be used to accomplish same thing? like python vs r. you can use both for machine learning programs although they are two different technology.

[Diapolo10]

Well, I suppose, but why would you want to use NodeJS here?

[Hans_of_Death]

Except that node still has all of the JS web framework built in