The file generation application running on the server will be generated to the local PC.

Thank you for your help.
Could you tell me about the relationship between the server and the local PC network?
Currently
using nuxt.js and firebase I am developing a printing application for a certain document.

It uses nuxt.js servermiddleware to generate pdf from the main body application.
Post the form with axios to /api/pdf
The specification is to generate a pdf file into the static directory of nuxt, such as hoge.pdf.

The host of the application is 127.0.0.1.
port is 3100
The server has a Ubuntu 18.04.2 LTS operating system. The web server is nginx.

When running the app in this way on the server

on the local PC 127.0.0.1: Test running a similar app on 3100

The destination of the pdf is the static directory of the nuxt on the local machine.

I don't know much about the network myself, but
In my interpretation, 127.0.0.1 is a private ip. I don't think it should be shared with external machines, but is it different?

Why is the app running on server 127.0.0.1
Does it affect the application running on the local machine 127.0.0.1?

By the way, if you close the app that runs on the local 127.0.0.1
pdf does not generate pdf on the local machine or on the server side.

How does the network work around here?
Anyone familiar with the network
Could you please let me know?

Thank you for your cooperation.