Best practices for persistent database connections in Python when using Flask

Turns out there is a straightforward way to achieve what I was after. But as the commenters suggested, if it is at all possible to go the flask sqlalchemy route, then you might want to go that way. My approach to solving the problem is to save the connection object in a module level variable that is then imported as necessary. That way it will be available for use from within Flask and by other modules. Here is a simplified version of what I did:

app.py

from flask import Flask
from extensions import neo4j

app = Flask(__name__)
neo4j.init_app(app)

extensions.py

from neo4j_db import Neo4j

neo4j = Neo4j()

neo4j_db.py

from neo4j import GraphDatabase

class Neo4j:
    def __init__(self):
        self.app = None
        self.driver = None

    def init_app(self, app):
        self.app = app
        self.connect()

    def connect(self):
        self.driver = GraphDatabase.driver('bolt://xxx')
        return self.driver

    def get_db(self):
        if not self.driver:
            return self.connect()
        return self.driver

example.py

from extensions import neo4j

driver = neo4j.get_db()

And from here driver will contain the database driver that will persist across Flask requests.

Hope that helps anyone that has the same issue.

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Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)