• Flask-Mail for email management
• threading for sending emails asynchronously
• Flask-Bootstrap for working with HTML-forms
• Flask-WTF and wtforms for working with WEB-forms
• Flask-SQLAlchemy for working with DB models
• Flask-Migrate for migrating DB model (not data)
• Flask-Moment for working with date
• Flask-login for management user sessions after authentication;
• Werkzeug for password hashing;
• itsdangerous for creating encrypted tokens and validates them

This is a fake mail server that accepts email messages but instead of sending them, it prints them to the console in a separate terminal. To run it add these settings for Flask application:

config.py:

MAIL_SERVER = os.environ.get('MAIL_SERVER', 'localhost')
MAIL_PORT = int(os.environ.get('MAIL_PORT', '8025'))

or set environment variables:

export MAIL_SERVER=localhost
export MAIL_PORT=8025

After that open a second terminal session and run the following command on it:

(venv) $ python -m smtpd -n -c DebuggingServer localhost:8025

Inserting Records:

./manage.py shell
User.query.all()
u1 = User(email='[email protected]', username='test')
db.session.add(u)
db.session.commit()

Querying Records:

User.query.filter_by(username='test').first()
User.query.filter_by(username='test').first().confirmed

Deleting Records:

./manage.py shell
u = User(username='test')
db.session.delete(u)
db.session.commit()

Update data for existing Records:

./manage.py shell
>>> User.query.filter_by(username='purple').first()
<User 'purple'>
>>> User.query.filter_by(username='purple').first().role_id
>>> User.query.filter_by(username='purple').first().__init__()
>>> User.query.filter_by(username='purple').first().role_id
1
>>> db.session.commit()
>>> exit()

Deleting Existing Records:

./manage.py shell
>>> User.query.all()
[<User 'purple5'>, <User 'test2'>]
>>> User.query.filter_by(username='test2').first().id
10
>>> User.query.filter_by(id=10).delete()
1
>>> User.query.all()
[<User 'purple5'>]
>>> db.session.commit()

DB migration:

1. Create .flaskenv:

   pip install python-dotenv

   Remember that the flask command puts in the environment variable FLASK_APP to know where the Flask application is located.

2. Create repository for migration:

   (venv) $ flask db init
     Creating directory <path>/purple/migrations ...  done
     Creating directory <path>/purple/migrations/versions ...  done
     Generating  <path>/purple/migrations/env.py ...  done
     Generating  <path>/purple/migrations/script.py.mako ...  done
     Generating  <path>/purple/migrations/alembic.ini ...  done
     Generating  <path>/purple/migrations/README ...  done
     Please edit configuration/connection/logging settings in ' <path>/purple/migrations/alembic.ini' before proceeding.
   

3. Creates a snapshot of the database (model) from the code:

   (venv) $ flask db migrate -m "add roles"
       INFO  [alembic.runtime.migration] Context impl SQLiteImpl.
       INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
       INFO  [alembic.autogenerate.compare] Detected added column 'roles.default'
       INFO  [alembic.autogenerate.compare] Detected added column 'roles.permissions'
       INFO  [alembic.autogenerate.compare] Detected added index 'ix_roles_default' on '['default']'
         Generating /<path>/purple/migrations/versions/835a1164988b_add_roles.py ...  done
   

4. Update the database structure (tables, but not data):

   (venv) $ 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 b0cc2a37fb87 -> 835a1164988b, add roles
   

Run unittests:

(venv) $ ./manage.py test
    test_app_exists (test_basics.BasicsTestCase) ... ok
    test_app_is_testing (test_basics.BasicsTestCase) ... ok
    test_duplicate_email_change_token (test_user_model.UserModelTestCase) ... ok
    test_expired_confirmation_token (test_user_model.UserModelTestCase) ... ok
    test_valid_reset_token (test_user_model.UserModelTestCase) ... ok
    ----------------------------------------------------------------------
    Ran 5 tests in 9.171s
    
    OK