'No application found. Either work inside a view function or push an application context.' [duplicate]

问题

This question already has answers here:

creating a database outside the application context (3 answers)

When scattering Flask Models, RuntimeError: 'application not registered on db' was raised (2 answers)

Closed 2 years ago.

I'm trying to separate my Flask-SQLAlchemy models into separate files. When I try to run db.create_all() I get No application found. Either work inside a view function or push an application context.

shared/db.py:

from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()

app.py:

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from shared.db import db

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'My connection string'
db.init_app(app)

user.py:

from shared.db import db

class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    email_address = db.Column(db.String(300), unique=True, nullable=False)
    password = db.Column(db.Text, nullable=False)

回答1:

Use with app.app_context() to push an application context when creating the tables.

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'My connection string'
db.init_app(app)

with app.app_context():
    db.create_all()

来源：https://stackoverflow.com/questions/46540664/no-application-found-either-work-inside-a-view-function-or-push-an-application