部署Python Flask包时出现问题，更具体地说，无法打开数据库文件

Question

显示的错误消息为sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file (Background on this error at: https://sqlalche.me/e/14/e3q8)Traceback将错误声明为fighters = Fighter.query.all()我尝试过不同的方法

战斗机.查询.获取(战斗机(

`我刚试过

fighters=Fighter.query.order_by('id'(.all((

我也遇到了同样的错误，这让我认为这是初始化数据库或数据库路径的问题。

我不确定是创建数据库还是查询结果。

我在run.py文件中的代码如下-

import os
from flask import Flask, render_template
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)
# DATABASE_URL is by default
app.config['SQLALCHEMY_DATABASE_URI'] = os.environ.get('DATABASE_URL', 'sqlite:///tmp/test.db')
db = SQLAlchemy(app)
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
email = db.Column(db.String(120), unique=True)
def __init__(self, email):
self.email = email
def __repr__(self):
return '<User %r>' % self.email

class Fighter(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(120), unique=True)

class Vote(db.Model):
id = db.Column(db.Integer, primary_key=True)
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
user = db.relationship('User', backref=db.backref('votes', lazy='dynamic'))
fighter_id = db.Column(db.Integer, db.ForeignKey('fighter.id'))
fighter = db.relationship('Fighter', backref=db.backref('votes', lazy='dynamic'))

@app.route('/', methods=['GET', 'POST'])
def homepage():
fighters = Fighter.query.all()
return render_template('index.html', fighters=fighters)

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

我的init_db.py文件如下所示-

from run import db, Fighter
# Create all the tables
db.create_all()
# create fighters
conor = Fighter(name='Conor McGregor')
floyd = Fighter(name='Floyd Mayweather')
# add fighters to session
db.session.add(conor)
db.session.add(floyd)
# commit the fighters to database
db.session.commit()

Answer 1

尝试这个

app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///tmp/test.db'

而不是这个

app.config['SQLALCHEMY_DATABASE_URI'] = os.environ.get('DATABASE_URL', 'sqlite:///tmp/test.db')