I'm following precisely your Flask Mega-Tutorial (I bought the book ;-)). I'm using windows, and pipenv for my virtual environments.

After executing p.40 << flask db init >> command I gave a look to the env.py file and pylint showed the error in the subject: Module 'alembic.context' has no 'config' member

Nevertheless I run << flask db migrate -m "users table" >> and I had the following error: sqlalchemy.exc.NoSuchModuleError: Can't load plugin: sqlalchemy.dialects:sqllite

Thank you in advance. Roberto

I am trying to get the "python manage.py db migrate" to work but I keep getting these two lines only.

INFO [alembic.runtime.migration] Context impl PostgresqlImpl. INFO [alembic.runtime.migration] Will assume transactional DDL.

Can someone explains what does the two lines mean? I am guessing the heroku backend that I am having couldn't compare the models.py and update the table. Correct me if I am wrong.

In my view.py, I have "from models import *" and in my app.py, I have "from view.py".

My friend has no problem migrating the database at all and he couldn't remember what he did to solve it.

I ran "python manage.py db show" and it shows me this

empty message

Revision ID: b8b188e67d59 Revises: 5b82870de25a Create Date: 2018-08-31 13:24:27.359151

I ran this "select * from alembic_version;" and I get

version_num 32a4b24d4961

Please let me know if the numbers makes any sense or the numbers are not helping at all. I just want to be able to update the table using the migrate and upgrade command whenever I add a column. and I have no idea what preventing it from reading my models.

With SQLALCHEMY_DATABASE_URI = 'sqlite://', upgrade() doesn't appear to create tables.

My tests fail with: OperationalError: (sqlite3.OperationalError) no such table

I run

$ python run.py db init

And that runs without issue. Then,

$ python run.py db migrate -m 'First migration'
Traceback (most recent call last):
  File "run.py", line 3, in <module>
    myapp.manager.run()
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/flask_script/__init__.py", line 412, in run
    result = self.handle(sys.argv[0], sys.argv[1:])
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/flask_script/__init__.py", line 383, in handle
    res = handle(*args, **config)
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/flask_script/commands.py", line 216, in __call__
    return self.run(*args, **kwargs)
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/flask_migrate/__init__.py", line 136, in migrate
    version_path=version_path, rev_id=rev_id)
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/alembic/command.py", line 113, in revision
    script.run_env()
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/alembic/script.py", line 390, in run_env
    util.load_python_file(self.dir, 'env.py')
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/alembic/util.py", line 243, in load_python_file
    module = load_module_py(module_id, path)
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/alembic/compat.py", line 79, in load_module_py
    mod = imp.load_source(module_id, path, fp)
  File "migrations/env.py", line 19, in <module>
    config.set_main_option('sqlalchemy.url', current_app.config.get('SQLALCHEMY_DATABASE_URI'))
  File "/Users/bfh/.virtualenvs/myapp/lib/python2.7/site-packages/alembic/config.py", line 198, in set_main_option
    self.file_config.set(self.config_ini_section, name, value)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/ConfigParser.py", line 743, in set
    raise TypeError("option values must be strings")
TypeError: <flask_script.commands.Command object at 0x107aba950>: option values must be strings

Any advice for a fella?

Hi Miguel!

I'm attempting to use your flask-migrate CLI tool as per your tutorial.

Issue: Running flask db init from the terminal fails with error:

    directory = current_app.extensions['migrate'].directory
KeyError: 'migrate' 

Desired result: flask db init should create the database (sqlite) and initialize database tables from all models.

Context:

1. I've exported FLASK_APP='run.py', where run.py does the import of 'app' and 'db' from (myapp)/__init__.py
2. Flask app is created with: app = Flask(APP_NAME) in run.py
3. DB object is created with: db = SQLAlchemy(app) in run.py

Speculative analysis: It seems that current_app.extensions is not somehow being populated with a desired key migrate, which I assume refers to your Flask extension.

Where/how is that supposed to happen?

There may be steps here I've missed or required parameters I'm unaware of. Can you point me in the right direction?

Thanks!

Hello there, I'm in a huge pickle. Flask-Migrate is not generating any migrations. I keep getting the following:

INFO  [alembic.runtime.migration] Context impl PostgresqlImpl.
INFO  [alembic.runtime.migration] Will assume transactional DDL.
INFO  [alembic.env] No changes in schema detected.

My directory structure is as follows:

.
├── app
│   ├── config.py
│   ├── credentials.json
│   ├── database.py
│   ├── errors.py
│   ├── factory.py
│   ├── fake.json
│   ├── models
│   │   ├── helium.py
│   │   ├── __init__.py
│   │   ├── logs.py
├── app.db
├── credentials.json
├── env-example
├── fake.json
├── migrations
│   ├── alembic.ini
│   ├── env.py
│   ├── env.pyc
│   ├── README
│   ├── script.py.mako
│   └── versions
├── pytest.ini
├── README.md
├── requirements.txt
├── run.py
├── sample-loan.json
├── tasks.py
├── test.sh
├── worker.sh
├── wsgi.py

Here's my main __init__.py file:

from .factory import Factory


def create_app(environment='development'):
    factory = Factory(environment)
    factory.set_flask()
    factory.set_celery()

    factory.set_db()
    factory.set_migration()
    from . import models


    factory.register(lms_blueprint)
    factory.register(mifos_blueprint)
    factory.register(br_blueprint)

    return factory.flask

My model's __init__.py file is as follows:

__all__ = ['helium', 'logs']

My database.py file is as follows:

from flask_migrate import Migrate
from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()
migrate = Migrate()

They are later initialized in factory.py below:

from __future__ import absolute_import

import logging
import logging.config
import os
import sys
from logging.handlers import RotatingFileHandler

from flask import Flask

from .config import config
from .database import db, migrate
from .tasks import celery_app, redis


class Factory:

    def __init__(self, environment='development'):
        self._environment = os.environ.get('APP_ENVIRONMENT', environment)

    @property
    def environment(self):
        return self._environment

    @environment.setter
    def environment(self, environment):
        self._environment = environment
        self.flask.config.from_object(config[self._environment])

    def set_flask(self, **kwargs):
        self.flask = Flask(__name__, **kwargs)
        self.flask.config.from_object(config[self._environment])
        # setup logging
        file_handler = RotatingFileHandler('br.log', maxBytes=10000, backupCount=1)
        file_handler.setLevel(logging.INFO)
        self.flask.logger.addHandler(file_handler)
        stdout = logging.StreamHandler(sys.stdout)
        stdout.setLevel(logging.DEBUG)
        self.flask.logger.addHandler(stdout)
        # werkzeug = logging.getLogger('werkzeug')
        # werkzeug.setLevel(logging.DEBUG)
        # self.flask.logger.addHandler(werkzeug)
        return self.flask

    def set_celery(self, **kwargs):
        return celery_app

    def set_db(self):
        db.init_app(self.flask)
        return db

    def set_migration(self):
        migrate.init_app(self.flask, db)
        return migrate

I can't get it to work with sqlite or postgres. I'm not sure if my directory structure is the problem or I'm missing a step. Some guidance would be highly appreciated.

Thanks.

Greetings. I am doing a project and I need to migrate to several databases simultaneously. For example, I have bind 2 databases in SQLALCHEMY_BINDS like that :

 **app.config['SQLALCHEMY_BINDS'] = {
'bobkov1': 'postgresql://postgres:zabil2012@localhost:5431/bobkov1',
'bobkov' : 'postgresql://postgres:zabil2012@localhost:5431/bobkov'

}**

And now i want to migrate models to both of this databases. I'm tried to do it like that:

**class User(BaseModel, db.Model): tablename = 'user' bind_key = {'bobkov','bobkov1'}

id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(64), index=True, unique=True)
email = db.Column(db.String(120), index=True, unique=True)
password_hash = db.Column(db.String(128))
posts = db.relationship('Post', backref='author', lazy='dynamic')

class Post(db.Model): tablename = 'post' bind_key = {'bobkov','bobkov1'} id = db.Column(db.Integer, primary_key=True) body = db.Column(db.String(140)) user_id = db.Column(db.Integer, db.ForeignKey('user.id'))**

When trying to run this code, the model migrates only to the main database, which is defined in SQLALCHEMY_DATABASE_URI.

Help me please, how to configure that?

when I try to run heroku flask db migrate or heroku flask db upgrade on Heroku. Heroku gives me the error below:

Traceback (most recent call last): File "/app/.heroku/python/bin/flask", line 8, in sys.exit(main()) File "/app/.heroku/python/lib/python3.6/site-packages/flask/cli.py", line 967, in main cli.main(args=sys.argv[1:], prog_name="python -m flask" if as_module else None) File "/app/.heroku/python/lib/python3.6/site-packages/flask/cli.py", line 586, in main return super(FlaskGroup, self).main(*args, **kwargs) File "/app/.heroku/python/lib/python3.6/site-packages/click/core.py", line 782, in main rv = self.invoke(ctx) File "/app/.heroku/python/lib/python3.6/site-packages/click/core.py", line 1259, in invoke return _process_result(sub_ctx.command.invoke(sub_ctx)) File "/app/.heroku/python/lib/python3.6/site-packages/click/core.py", line 1259, in invoke return _process_result(sub_ctx.command.invoke(sub_ctx)) File "/app/.heroku/python/lib/python3.6/site-packages/click/core.py", line 1066, in invoke return ctx.invoke(self.callback, **ctx.params) File "/app/.heroku/python/lib/python3.6/site-packages/click/core.py", line 610, in invoke return callback(*args, **kwargs) File "/app/.heroku/python/lib/python3.6/site-packages/click/decorators.py", line 21, in new_func return f(get_current_context(), *args, **kwargs) File "/app/.heroku/python/lib/python3.6/site-packages/flask/cli.py", line 426, in decorator return __ctx.invoke(f, *args, **kwargs) File "/app/.heroku/python/lib/python3.6/site-packages/click/core.py", line 610, in invoke return callback(*args, **kwargs) File "/app/.heroku/python/lib/python3.6/site-packages/flask_migrate/cli.py", line 134, in upgrade _upgrade(directory, revision, sql, tag, x_arg) File "/app/.heroku/python/lib/python3.6/site-packages/flask_migrate/init.py", line 96, in wrapped f(*args, **kwargs) File "/app/.heroku/python/lib/python3.6/site-packages/flask_migrate/init.py", line 269, in upgrade config = current_app.extensions['migrate'].migrate.get_config(directory, KeyError: 'migrate'

python manage.py db init && python manage.py db migrate && python manage.py db upgrade

All commands run without error messages yet no tables were created. Here are the relevant files:

project/__init__.py

from flask import Flask
from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()

def create_app():
    app = Flask(__name__)
    app.config.from_object(os.environ['APP_SETTINGS'])
    db.init_app(app)
    return app

run.py

from project import create_app
app = create_app()

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

manage.py

from flask_script import Manager
from flask_migrate import Migrate, MigrateCommand
from project.models import *
from flask_sqlalchemy import SQLAlchemy
from run import app


db = SQLAlchemy(app)

migrate = Migrate(app, db)
manager = Manager(app)

manager.add_command('db', MigrateCommand)

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

I'm trying to change my project from a single database to multiple databases. I'm still building it, so it doesn't matter if I lose all of my data. But every time I do a flask db init --multidb and then try to run a flask db migrate, I get the below error:

sqlalchemy.exc.OperationalError: (pyodbc.OperationalError) ('08001', '[08001] [Microsoft][ODBC Driver 17 for SQL Server]Neither DSN nor SERVER keyword supplied (0) (SQLDriverConnect)')

If I run the init again without the multidb tag, everything works.

Looking at the below item, it seems like it might be an SSL issue, but I'm not sure how to use any of the solutions, since I'm on a Windows computer. https://github.com/mkleehammer/pyodbc/issues/610

My app.py

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_script import Manager
from flask_migrate import Migrate, MigrateCommand
from config import Config

app = Flask(__name__)
app.debug = True
app.config.from_object(Config)

db = SQLAlchemy(app)
from models import Users

migrate = Migrate(app, db)
manager = Manager(app)
manager.add_command('db', MigrateCommand)



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

models.py

from app import db, app from datetime import date, datetime

class Users(db.Model):
    # Users
    __tablename__ = 'users'
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    username = db.Column(db.String(120), index=True, unique=True)
    last_name = db.Column(db.String(128))
    first_name = db.Column(db.String(128))
    created = db.Column(db.DateTime, default=datetime.now())
    user_days = db.relationship("Days", back_populates="user_days")
    user_tasks = db.relationship("Tasks", back_populates="user_tasks")
    user_chats = db.relationship("Chats", back_populates="user_chats")

    def __init__(self, username, last_name, first_name):
        self.username = username
        self.last_name = last_name
        self.first_name = first_name

    def __repr__(self):
        return '<User {}>'.format(self.username)

Run commands:

python app.py db init
python app.py db migrate
python app.py db upgrade

And have a problem:

Traceback (most recent call last):
  File "app.py", line 12, in <module>
    from models import Users
  File "C:\Users\vandr\PycharmProjects\telegrambot_with_flask\models.py", line 1, in <module>
    from app import db, app
  File "C:\Users\vandr\PycharmProjects\telegrambot_with_flask\app.py", line 12, in <module>
    from models import Users
ImportError: cannot import name 'Users'

Can you help me?

With flask-alchemy 3.1.0 all works as expected. We add a column to one of the tables of the db.Model and all works as expected. It detected added columns and a new versions file is generated.

After upgrade from flask-alchemy 3.1.0 to flask-alchemy 4.0.0 fails to detect any changes and generate a new versions file. There are no errors reported. It seems to fail to dive into the alembic.runtime.migration

See attached logs

flask-migrate_310.log poetry upgrade.log flask-migrate_400.log

Hi there,

I started to run into a weird issue in my GitHub actions. Sometimes my migrations just don't want to apply on my Postgres DB:

The output of the step running on GitHub actions:

INFO  [alembic.runtime.migration] Context impl PostgresqlImpl.
INFO  [alembic.runtime.migration] Will assume transactional DDL.
INFO  [alembic.runtime.migration] Running upgrade 616e0cbe0c24 -> 7001b6cb06f8, empty message.
1

The step does nothing difficult:

docker-compose run --rm app sh -c "wait-for-it.sh db:5432 -- flask db upgrade -d /app/migrations heads"

The migration itself is also easy:

def upgrade():
    with op.get_context().autocommit_block():
        op.execute(
            """
            ALTER TYPE aggregationperiodtype ADD VALUE IF NOT EXISTS 'WEEKLY';
            """
        )

This happens randomly (not always on this migration, sometimes on different and sometimes it passed without an error). Is it also possible to get more detail on this kind of error?

requirements: Werkzeug==2.2.2 Flask==2.0.3 Flask-Migrate==3.1.0 Flask-SQLAlchemy==2.5.1 SQLAlchemy==1.4.31

We are using Flask-Migrate(version 3.1.0) from a long time and it used to work fine with our previous flask version BUT after upgrading our Flask version to 2.1.3 it's producing the below error on any flask db command

Traceback (most recent call last):
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/bin/flask", line 8, in <module>
    sys.exit(main())
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/flask/cli.py", line 986, in main
    cli.main()
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/flask/cli.py", line 567, in main
    return super().main(*args, **kwargs)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/click/core.py", line 1055, in main
    rv = self.invoke(ctx)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/click/core.py", line 1657, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/click/core.py", line 1657, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/click/core.py", line 1404, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/click/core.py", line 760, in invoke
    return __callback(*args, **kwargs)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/click/decorators.py", line 26, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/flask/cli.py", line 407, in decorator
    return __ctx.invoke(f, *args, **kwargs)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/click/core.py", line 760, in invoke
    return __callback(*args, **kwargs)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/flask_migrate/cli.py", line 104, in migrate
    _migrate(directory, message, sql, head, splice, branch_label, version_path,
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/flask_migrate/__init__.py", line 98, in wrapped
    f(*args, **kwargs)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/flask_migrate/__init__.py", line 155, in migrate
    command.revision(config, message, autogenerate=True, sql=sql,
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/command.py", line 229, in revision
    script_directory.run_env()
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/script/base.py", line 569, in run_env
    util.load_python_file(self.dir, "env.py")
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/util/pyfiles.py", line 94, in load_python_file
    module = load_module_py(module_id, path)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/util/pyfiles.py", line 110, in load_module_py
    spec.loader.exec_module(module)  # type: ignore
  File "<frozen importlib._bootstrap_external>", line 850, in exec_module
  File "<frozen importlib._bootstrap>", line 228, in _call_with_frames_removed
  File "migrations/env.py", line 98, in <module>
    run_migrations_online()
  File "migrations/env.py", line 92, in run_migrations_online
    context.run_migrations()
  File "<string>", line 8, in run_migrations
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/runtime/environment.py", line 853, in run_migrations
    self.get_context().run_migrations(**kw)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/runtime/migration.py", line 611, in run_migrations
    for step in self._migrations_fn(heads, self):
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/command.py", line 205, in retrieve_migrations
    revision_context.run_autogenerate(rev, context)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/autogenerate/api.py", line 526, in run_autogenerate
    self._run_environment(rev, migration_context, True)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/autogenerate/api.py", line 544, in _run_environment
    if set(self.script_directory.get_revisions(rev)) != set(
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/script/base.py", line 296, in get_revisions
    self.revision_map.get_revisions(id_),
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/script/revision.py", line 527, in get_revisions
    return sum([self.get_revisions(id_elem) for id_elem in id_], ())
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/script/revision.py", line 527, in <listcomp>
    return sum([self.get_revisions(id_elem) for id_elem in id_], ())
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/script/revision.py", line 552, in get_revisions
    return tuple(
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/script/revision.py", line 553, in <genexpr>
    self._revision_for_ident(rev_id, branch_label)
  File "/Users/vinitpayal/engineering/tribes/codes/backend-api-python-3/venv/lib/python3.9/site-packages/alembic/script/revision.py", line 613, in _revision_for_ident
    assert resolved_id
AssertionError

The error appears on all

flask db migrate -m
flask db upgrade

The error is being raised from a function named _revision_for_ident in dependency alembic BUT not sure what can be the cause of it and have no idea about how we can get it fixed.

I want to be able to specify a username:password to Flask-Migrate with permissions to alter tables and drop and create tables, but I don't want my SQLAlchemy user to have those permissions. SQLAlchemy should only be able to insert, update, select and join. Is this possible at the moment? If so, how would I do that?

Hi

just trying to build the package for openSUSE and I'm getting

Error: No such template 'custom_template'

when running the tests. The tar-ball seems to have the custom_template directory missing that's in the test directory, is that the issue?

run

flask db migrate
# return success

# then
flask db upgrade
# return failed
# o my models file define error,  so i corrected it.
# then run
flask db migrate
# return:   ERROR [flask_migrate] Error: Target database is not up to date.

What do I do in this case next?

i fix models file, but can’t migrate or upgrade again.

one way is delete all file, and db init again, but this is not what I want.