Flask, SQLAlchemy cannot retrieve data from db, and send it in GET request

问题

I''m still new to Flask/SQLAlchemy. I made this where I was having context issues. I've managed to fixed the SQLAlchemey issue, but now I am unable to retrieve data from my postgres DB

I have a separate directory for models, routes and a main app.py file. I'm initializing my db in app.py, importing the db in models.model and creating a basic class. I've managed to add data manually in python terminal and by hard coding a new class in the app.py file. I see this table/data in postgres.

The next thing I'd like to do is retrieve this data in one of my routes, and send it as part of a Get request. Below is code for all 2 files.

app.py

from flask import Flask
from flask_restful import Api
from flask_sqlalchemy import SQLAlchemy

from my_routes.user import User

app = Flask(__name__)
app.config.from_pyfile('config.py')
api = Api(app)
db = SQLAlchemy(app)

from models.model import Task

db.create_all()
db.session.commit()

# task = Task(4, 'nothing yet')
# db.session.add(task)
# db.session.commit()
# task = Task.query.all()
# print (task)


# api.add_resource(root.HelloWorld, '/')
api.add_resource(User, '/user')
# api.add_resource(MyTest, '/test')

if __name__ == '__main__':
    app.run()

models.model

from app import db

class Task(db.Model):
    id = db.Column('id', db.Integer, primary_key=True)
    data = db.Column('data', db.Unicode)

    def __init__(self, id, data):
        self.id = id
        self.data = data

routes.my_test.MyTest

from flask_restful import Resource
from models.model import Task

class MyTest(Resource):
    def get(self):
        first_task = Task.query.first()
        return {'test route': first_task}

When I try to run app.py, I get the following error:

ImportError: cannot import name 'Task'

How do I go about fixing this import error, and making data from my Task table available to all my routes?

来源：https://stackoverflow.com/questions/49102195/flask-sqlalchemy-cannot-retrieve-data-from-db-and-send-it-in-get-request

标签

python-3.x

postgresql

Flask

flask-sqlalchemy