sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) no such table
I just got done setting up a Flask app and I dealt with this kind of problem.
I strongly suspect the problem here is that the instance of db
that you are creating in __init__.py
is unaware of the contents of models.py
, including the User
class. The db
object in __init__.py
is a totally separate object from the db
you are creating in models.py
. So when you run db.create_all()
in __init__.py
, it is checking the list of tables that it knows about and isn't finding any. I ran into this exact issue.
What I discovered is that the models (like User
) are registered with the particular db
object that is listed in the model's class definition (e.g. class User(db.Model):
).
So basically my understanding is that the way to fix this is to run db.create_all()
using the same instance of db
that is being used to define the models. In other words, run db.create_all()
from within models.py
.
Here's my code so you can see how I have it set up:
app.py
:
#!flask/bin/python
import os
from flask import Flask
class CustomFlask(Flask):
jinja_options = Flask.jinja_options.copy()
jinja_options.update(dict(
variable_start_string='%%', # Default is '{{', I'm changing this because Vue.js uses '{{' / '}}'
variable_end_string='%%',
))
app = CustomFlask(__name__)
app.config['SECRET_KEY'] = 'hard to guess string'
import yaml
if os.environ['SERVER_ENVIRONMENT'] == 'PRODUCTION':
config_filename = "production.yaml"
elif os.environ['SERVER_ENVIRONMENT'] == 'LOCAL':
config_filename = "local.yaml"
else:
config_filename = "local.yaml"
base_directory = path = os.path.dirname(os.path.realpath(__file__))
with open(base_directory + "/config/" + config_filename) as config_file:
config = yaml.load(config_file)
db_config = config['database']
SQLALCHEMY_DATABASE_URI = "mysql+mysqlconnector://{username}:{password}@{hostname}/{databasename}".format(
username=db_config['username'],
password=db_config['password'],
hostname=db_config['hostname'],
databasename=db_config['databasename'],
)
app.config["SQLALCHEMY_DATABASE_URI"] = SQLALCHEMY_DATABASE_URI
app.config["SQLALCHEMY_POOL_RECYCLE"] = 299
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy(app)
db.app = app
def clear_the_template_cache():
app.jinja_env.cache = {}
app.before_request(clear_the_template_cache)
from flask_login import LoginManager
login_manager = LoginManager()
login_manager.init_app(app)
@login_manager.user_loader
def load_user(email):
from models import User
return User.query.filter_by(email=email).first()
if __name__ == '__main__':
from routes import web_routes
app.register_blueprint(web_routes)
from api import api
app.register_blueprint(api)
# To get PyCharm's debugger to work, you need to have "debug=False, threaded=True"
#app.run(debug=False, threaded=True)
app.run(debug=True)
models.py
:
from app import db
import datetime
from werkzeug.security import generate_password_hash, \
check_password_hash
class Song(db.Model):
id = db.Column(db.Integer, primary_key=True, autoincrement=True)
name = db.Column(db.String(80))
datetime_created = db.Column(db.DateTime, default=datetime.datetime.utcnow())
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
lines = db.relationship('Line', cascade="all,delete", backref=db.backref('song', lazy='joined'), lazy='dynamic')
is_deleted = db.Column(db.Boolean, default=False)
class Line(db.Model):
id = db.Column(db.Integer, primary_key=True, autoincrement=True)
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
song_id = db.Column(db.Integer, db.ForeignKey('song.id'))
spans_of_time = db.relationship('SpanOfTime', cascade="all,delete", backref=db.backref('line', lazy='joined'), lazy='dynamic')
class SpanOfTime(db.Model):
id = db.Column(db.Integer, primary_key=True, autoincrement=True)
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
line_id = db.Column(db.Integer, db.ForeignKey('line.id'))
starting_64th = db.Column(db.Integer) # I'm assuming the highest-granularity desired will be a 1/64th note-length.
length = db.Column(db.Integer) # I guess this'll be in 1/64th notes, so a 1/16th note will be '4'.
content = db.Column(db.String(80))
class User(db.Model):
id = db.Column(db.Integer, primary_key=True, autoincrement=True)
email = db.Column(db.String(80), primary_key=True, unique=True)
display_name = db.Column(db.String(80), default="A Rhymecraft User")
password_hash = db.Column(db.String(200))
datetime_subscription_valid_until = db.Column(db.DateTime, default=datetime.datetime.utcnow() - datetime.timedelta(days=1))
datetime_joined = db.Column(db.DateTime, default=datetime.datetime.utcnow())
songs = db.relationship('Song', cascade="all,delete", backref=db.backref('user', lazy='joined'), lazy='dynamic')
def __init__(self, email, password):
self.email = email
self.set_password(password)
def __repr__(self):
return '<User %r>' % self.email
def set_password(self, password):
self.password_hash = generate_password_hash(password)
def check_password(self, password):
return check_password_hash(self.password_hash, password)
def is_authenticated(self):
return True
def is_active(self):
return True
def is_anonymous(self):
return False
def get_id(self):
return str(self.email)
def init_db():
db.create_all()
# Create a test user
new_user = User('[email protected]', 'aaaaaaaa')
new_user.display_name = 'Nathan'
db.session.add(new_user)
db.session.commit()
new_user.datetime_subscription_valid_until = datetime.datetime(2019, 1, 1)
db.session.commit()
if __name__ == '__main__':
init_db()
Very simple solution: in the app.py or main.py you can just add these lines of code for fixing this issue:
@app.before_first_request
def create_tables():
db.create_all()
In your case, require to add following code into __init__.py:
from models import User, Role
@app.shell_context_processor
def make_shell_context():
return dict(db=db, User=User, Role=Role)
then you do your previous works, it's all work.