To run this application, follow these steps:

1. Create a .env File:

   Create a file named .env in the root directory of your project.

2. Insert the Following Credentials:

   Open the .env file and insert the following lines, replacing the placeholders with your actual credentials:

   # .env
   
    DEBUG=True
    PORT=5000
    HOST=0.0.0.0
    DB_URI=postgresql://postgres:root@localhost:5432/TaskManager
   SECRET_KEY=your_flask_secret_key
   SQLALCHEMY_TRACK_MODIFICATIONS=False
   RESULT_BACKEND=rpc://
   BROKER_URL=pyamqp://guest:guest@localhost:5672//

   Adjust these values based on your specific database and application configuration.

3. Save and Close the File:

   Save the changes to the .env file and close it.

Below are the common commands used for managing database migrations in a Flask application using Flask-Migrate and Flask-Script.

1. Initialize the Migration Repository:

   python manage.py db init

   This command initializes a new migration repository. Run this command only once when setting up your project.

2. Generate a Migration:

   python manage.py db migrate -m "Your migration message"

   This command generates a new migration based on changes in your models. Run this command every time you make changes to your database models.

3. Apply Migrations:

   python manage.py db upgrade

   This command applies any pending migrations to the database.

4. Downgrade a Migration:

   python manage.py db downgrade

   This command rolls back the last applied migration. Use it with caution, especially in production environments.

5. Show the List of Migrations:

   python manage.py db history

   This command displays a list of migrations and their statuses.

6. Show the Current Revision:

   python manage.py db current

   This command shows the current revision of the database.