Flask - migration in specific folder

Change default directory of migration.

step1. Make new folder: Resources

step2. Move current files to new folder

• open migrations/versions
• move files into the new folder

step3. set new directory location in main.py

• pip install Flask-Script needed.
• should working with requirement later.

import os
from flask_script import Manager
from flask_migrate import Migrate, MigrateCommand
#from myapp import app, db
#from myapp.models import User, Post


MIGRATION_DIR = os.path.join('resources')

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

manager.add_command('db', MigrateCommand)

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

@app.shell_context_processor
def make_shell_context():
    return {'db': db, 'User': User, 'Post': Post}

setp4. when model updated

• update models.py first

  class User(UserMixin, db.Model):
    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') # post.author ==> user instance
    about_me = db.Column(db.String(140))
    last_seen = db.Column(db.DateTime, default=datetime.utcnow)
  

• do migration in terminal
• don’t forget flask db migrate -m "message"

(venv) (base) ➜  microblog git:(master) ✗ flask db migrate -m "about me and last seen in User model"
INFO  [alembic.runtime.migration] Context impl SQLiteImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
INFO  [alembic.autogenerate.compare] Detected added column 'user.about_me'
INFO  [alembic.autogenerate.compare] Detected added column 'user.last_seen'
  Generating /Users/paduck/code/paduck210/microblog/resources/versions/21f1a3ec4311_about_me_and_last_seen_in_user_model.py ...  done

and should do flask db upgrade

(venv) (base) ➜  microblog git:(master) ✗ flask db upgrade
INFO  [alembic.runtime.migration] Context impl SQLiteImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
INFO  [alembic.runtime.migration] Running upgrade 1a79a82916d4 -> 21f1a3ec4311, about me and last seen in User model