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Can't serve swagger on remotely hosted server with different url

I'm trying to serve some simple service using flask and flask_restx (a forked project of flask-restplus, that would be eventually served on AWS.
When it is served, I want to generate swagger page for others to test it easily.
from flask import Flask
from flask_restx import Api
from my_service import service_namespace
app = Flask(__name__)
api = Api(app, version='1.0')
api.add_namespace(service_namespace)
if __name__ == '__main__':
app.run(debug=True)
When I test it locally (e.g. localhost:5000), it works just fine. Problem is, when it is hosted on AWS, because it has a specific domain (gets redirected?) (e.g. my-company.com/chris-service to a container), the document page is unable to find its required files like css and so:
What I've looked and tried
Python (Flask + Swagger) Flasgger throwing 404 error
flask python creating swagger document error
404 error in Flask
Also tried adding Blueprint (albeit without knowing exactly what it does):
app = Flask(__name__)
blueprint = Blueprint("api", __name__,
root_path="/chris-service",
# url_prefix="/chris-service", # doesn't work
)
api = Api(blueprint)
app.register_blueprint(blueprint)
...
And still no luck.
Update
So here's more information as per the comments (pseudo, but technically identical)
Access point for the swagger is my-company.com/chris (with or without http:// or https:// doesn't make difference)
When connecting to the above address, the request URL for the assets are my-company.com/swaggerui/swagger-ui.css
You can access the asset in my-company.com/chris/swaggerui/swagger-ui.css
So I my resolution (which didn't work) was to somehow change the root_path (not even sure if it's the correct wording), as shown in What I've looked and tried.
I've spent about a week to solve this but can't find a way.
Any help will be greatful :) Thanks

Swagger parameters defined at apidoc.py file. Default apidoc object also created in this file. So if you want to customize it you have change it before app and api initialization.
In your case url_prefix should be changed (I recommend to use environment variables to be able set url_prefix flexibly):
$ export URL_PREFIX='/chris'
from os import environ
from flask import Flask
from flask_restx import Api, apidoc
if (url_prefix := environ.get('URL_PREFIX', None)) is not None:
apidoc.apidoc.url_prefix = url_prefix
app = Flask(__name__)
api = Api(app)
...
if __name__ == '__main__':
app.run()

Always very frustrating when stuff is working locally but not when deployed to AWS. Reading this github issue, these 404 errors on swagger assets are probably caused by:
Missing javascript swagger packages
Probably not the case, since flask-restx does this for you. And running it locally should also not work in this case.
Missing gunicorn settings
Make sure that you are also setting gunicorn up correctly as well with
--forwarded-allow-ips if deploying with it (you should be). If you are in a kubernetes cluster you can set this to *
https://docs.gunicorn.org/en/stable/settings.html#forwarded-allow-ips
According to this post, you also have to explicitly set
settings.FLASK_SERVER_NAME to something like http://ec2-10-221-200-56.us-west-2.compute.amazonaws.com:5000
If that does not work, try to deploy a flask-restx example, that should definetely work. This rules out any errors on your end.

Flask Server not responding to HTTP POST Request

I built a simple flask server in order to automate python scripts based on an HTTP POST Request coming in from an outside service. This service sends these requests in response to events that we have created based on data conditions. All the flask server needs to do is parse the requests, and take the numerical value stored in the request and use it to run the corresponding python script. At one point, this system was working consistently. Fast forward a few months, the server was no longer working when tried again. No changes were made to the code. According to wireshark, The computer hosting the flask server is receiving the request to the correct port, but the request is now timing out. The host system is failing to respond to the request. Any Idea what is going on here? The firewall has temporarily been turned off.
Alternatively, is there another better package to achieve this goal with?
from flask import Flask, request
import threading
import runpy
app = Flask(__name__)
#app.route('/', methods=['POST'])
def PostHandler():
directory = {}
with open(r"M:\redacted") as f:
for line in f:
(key,val) = line.split()
directory[int(key)] = val
print(directory)
path = r"M:\redacted"
content = request.json
content = content['value']
print(content)
sel_script = int(content)
print(directory[sel_script])
runpy.run_path(path_name=path + directory[sel_script])
return
app.run(host="10.244.xx.xx", port=8080, threaded=True)

Publish a script online

I have a Python script written up and the output of this script is a list.
Right now I need to get it online and make it accessible to others. I looked at Django , but then I realized that it may be kind of hard to create the UI. Is there any simple way to create a UI in Django and map it to an existing Python script.
Right now I using nltk, numpy, sqlite3 and things like that. Or is there a simpler way by which I can proceed?

In your case, Django is redundant.
You can use something smaller, Flask or maybe Aiohttp.
For example, all you need in aiohttp:
basic hmtl template
handler for one url (here you will call your script)
aiohttp webserver
The main idea:
Your server catch some url (for example /),
start your script, receives result,
respond with your html template (also render script result in it).

You can try creating a flask App.
Just do a pip install Flask and try the code below
from flask import Flask
import flask
import json
from flask import Response
app = Flask(__name__)
#app.route('/test',methods=['GET'])
def test():
'''
GET: Receives the request in /test route and returns a response containing {"response": [1,2,3]}
'''
my_list = [1,2,3]
resp = Response(response=json.dumps({"response": my_list}), status=200, mimetype='application/json')
return resp
if __name__ == '__main__':
app.run(debug=True, host='0.0.0.0', port=8082)
Then to test your app from your browser accessing
localhost:8082/test
or also through some app like postman
I would suggest looking into something like React for creating the UI. This way your UI would only make calls to your Flask server.

How to pass URLs as parameters in a GET request within python flask (restplus)?

I am creating a REST API using python flask. The API is ready and works on port number 8000 of my localhost. Now I intend to give this REST API a user friendly interface for which I decided to go with python - restplus. I thought of calling this service (running on 8000) internally from swagger application running on 5000
I was able to create the basic structure of the API (Swagger). The code for which looks like this:
import flask
from flask import Flask, request
from flask_restplus import Resource, Api
app = Flask(__name__)
api = Api(app)
#api.route('/HybridComparator/<string:url2>/<string:url1>')
class HybridComparator(Resource):
def get(self, url1, url2):
print(url1)
print(url2)
return url1 + ' ' + url2
if __name__ == '__main__':
app.run(debug=True)
The application as a whole runs seamlessly (with random strings as parameters) on port 5000. But when the URLs I pass are actual links, the application returns a response of 404 - Not found. Further to my investigation I realized the culprit being '/' embedded within the links I try to provide. Is there a way to handle URLs in particular?
Should I encode them before sending a request. (This will make my parameters look ugly). Is there something I am missing?

This is an entirely old question and I am sure you solved your problem by now.
But for new searchers, this may come in handy;
replace <string:url2>/<string:url1> with <path:url2>/<path:url1>

it seems that :
#api.route('/HybridComparator/<path:url2>/<path:url1>')
should fix it ,it fixes the 404 but i am getting only "http:/" part of the param

Routes With Custom Domains Using Flask

My web app assigns a subdomain to users and optionally allows them to use a custom domain. This works except when the user visits their custom domain for a route without including a trailing slash.
GET requests to this url works as expected: http://user.example.com:5000/book/12345/
GET requests to this url works as expected: http://custom.com:5000/book/12345/
GET requests to this url attempt to redirect, but fail: http://custom.com:5000/book/12345
Flask ends up redirecting the browser to this url which, of course, doesn't work: http://<invalid>.example.com:5000/book/12345/
Is there a different way that I should handle custom domains? Here's a complete minimal example to reproduce this. I have set custom.com, example.com. and user.example.com to point to 127.0.0.1 in my /etc/hosts file in my development environment so that Flask receives the request.
from flask import Flask
app = Flask(__name__)
server = app.config['SERVER_NAME'] = 'example.com:5000'
#app.route('/', subdomain="<subdomain>")
#app.route('/')
def index(subdomain=None):
return ("index")
#app.route('/book/<book_id>/', subdomain="<subdomain>")
#app.route('/book/<book_id>/')
def posts(post_id, subdomain=None):
return (book_id)
if __name__ == '__main__':
app.run(host='example.com', debug=True)

I'm not sure that's possible. host matching and subdomain matching are mutually exclusive (look at host matching parameter).
I'd love to be wrong though.
One way around this issue that I can think of is to use something in front of Flask (say nginx) that points custom.com to custom.com._custom.example.com or something like that. In your code you could create a custom url_for function that would recognize this as a custom domain. I would ask on the Flask mailing list as they would be able to give you a solid answer.