Flask-SQLAlchemy error MySQL server has gone away - mysql

Question

I'm newbie running a Flask app connected to a MySQL remote server with Flask-SQLAlchemy.
The app has very little traffic and it's usual to stay idle for more than 8 hours, I then get disconnected from the MySQL server.
this is my app code:
from flask import Flask, render_template, request, redirect, jsonify, make_response
from flask_sqlalchemy import SQLAlchemy
from sqlalchemy import or_
app = Flask(__name__)
app.config['DEBUG'] = True
app.config['SQLALCHEMY_ENGINE_OPTIONS'] = {'pool_pre_ping': True, 'pool_recycle': 300, 'echo':'debug',}
app.config['SQLALCHEMY_DATABASE_URI']='mysql+pymysql://user:pass#myipcode/db'
db = SQLAlchemy(app)
Everything works ok until no querys are performed for 8 hours, then I lose db connection and logs show this error code:
"MySQL server has gone away (%r)" % (e,)) sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2006, "MySQL server has gone away (BrokenPipeError(32, 'Broken pipe'))
I did some research and was adviced to set 'SQLALCHEMY_ENGINE_OPTIONS' as written in the code sample but it behaves the same with or without such engine options, connection is not recycled every 300 seconds as It should, and pool_pre_ping doesn't seem to make any difference. 'echo':'debug' option works as intended since I get every transaction logged.
What should I do to prevent the connection from being disconnected even after a long period of inactivty?
EDIT:
To add some additional info:
The database is hosted in Cloud SQL from GCP .
I'm lost...
Any help would be greatly appreciated.

Answer 1

Finally I figured it out myself,
It had to do with the fact that my app was running on a mountpoint like http://ServerIP/app instead of http://ServerIP/ because it was initially intended as a staging server.
I was using uWSGI and, in order to make it work in the aforementioned path, I had to specify a mount parameter in the [UWSGI] block from app.ini file.
When the uWSGI server started it showed like it was mounting two apps, one in '' and the other in '/app', and I guess that created a conflict that made the app unable to manage connections on MySQL server.
Mounting the app in http://ServerIP/ worked like a charm.