- AirBnB_clone - a command interpreter to manipulate data without a visual interface, like in a Shell (perfect for development and debugging)
    - AirBnB_clone_v4 (this focus) - a website (the front-end) that shows the final product to everybody: static and dynamic - load objects from the client side by using from RESTful API

    - AirBnB_clone_v2 - a database or files that store data (data = objects)
    - AirBnB_clone_v3 - an API that provides a communication interface between the front-end and your data (retrieve, create, delete, update them):
        - expose all your objects stored via a JSON web interface
        - manipulate your objects via a RESTful API

.
├── AUTHORS - Docker specified formatted file for contributors
├── README.md - project documentation.
├── console.py - single-use command interpreter(uses Python `cmd` module).
├── models/ - the main driver of the project; lays out Python Object Orientation, initialization,  serialization, (de)serialization etc.
│   ├── __init__.py - effectively make a `Python` Package out of these modules, unique FileStorage instance for app
│   ├── base_model.py  - includes base (class) model ; for subclassing/inheritance - is the superclass.
│   ├── user.py - sample file with subclass of BaseModel(from module base_model)
│   ├── engine/ - abstracted storage engine/system for persisting data.
│   │   ├── __init__.py - effectively make a `Python` Package out of these modules
│   │   └── file_storage.py - module with methodes meant to interact with file storage(read from/write to JSON file), and models
└── tests/ - directory for unit testing, test cases/test suites etc.
    ├── __init__.py - effectively make a `Python` Package out of these modules, for Python test discovery.
    └── test_models/ - files that test models eg test_base_model.py, test_user.py, test_review.py
        └── __init__.py - effectively make a `Python` Package out of these modules, for Python test discovery.
...
├── web_dynamic - JavaScript jQuary, Flask Routing etc - focus of AirBnB v4
│   ├── *-hbnb.py - Routing file
│   ├── 100-dump.sql - file for database Dump to get mock data for user-facing of MVC
│   ├── static
│   │   ├── images
│   │   │   ├── icon.png
│   │   ├── scripts
│   │   │   └── *-hbnb.js - JQuery for DOM manipulation
│   │   └── styles - CSS
│   ├── templates - Jinja Templates
│   │   └── *-hbnb.html
│   └── w3c_validator.py
...
├── web_flask
│   ├── *.py - Flask routing files
│   ├── README.md
│   ├── __init__.py
│   ├── static
│   │   ├── images
│   │   │   └── logos/icons
│   │   └── styles - Cascading Style Sheets
│   │       └── *.css
│   └── templates - Jinja templating
│       └── *.html
└── web_static
    └── Frontend of the application directory hosting static files: CSS, HTML, Images.

$ cat setup_mysql_dev.sql | sudo mysql # -uroot -p # if root user uses passwd
$ cat web_dynamic/100-dump.sql | sudo mysql # -uroot -p # if root user uses passwd

# terminal 1:
$ HBNB_MYSQL_USER=hbnb_dev HBNB_MYSQL_PWD=hbnb_dev_pwd HBNB_MYSQL_HOST=localhost HBNB_MYSQL_DB=hbnb_dev_db HBNB_TYPE_STORAGE=db python3 -m web_dynamic.*-hbnb 
# where *-hbnb  is any of the Flask routing files

# terminal 2:
$ HBNB_MYSQL_USER=hbnb_dev HBNB_MYSQL_PWD=hbnb_dev_pwd HBNB_MYSQL_HOST=localhost HBNB_MYSQL_DB=hbnb_dev_db HBNB_TYPE_STORAGE=db HBNB_API_PORT=5001 python3 -m api.v1.app

# run the interpreter in interactive mode:
/AirBnB_clone$ ./console.py

# prompt designates you are in the "HBnB" console
(hbnb)

(hbnb) User.update("98bea5de-9cb0-4d78-8a9d-c4de03521c30", name "Todd the Toad")
(hbnb)
(hbnb) User.all()
(hbnb) ["[User] (98bea5de-9cb0-4d78-8a9d-c4de03521c30) {'updated_at': datetime.datetime(2020, 2, 19, 21, 47, 29, 134362), 'id': '98bea5de-9cb0-4d78-8a9d-c4de03521c30', 'name': 'Todd the Toad', 'created_at': datetime.datetime(2020, 2, 19, 21, 47, 29, 134343)}"]

(hbnb) User.update("98bea5de-9cb0-4d78-8a9d-c4de03521c30", {'name': 'Fred the Frog', 'age': 9})
(hbnb)
(hbnb) User.all()
(hbnb) ["[User] (98bea5de-9cb0-4d78-8a9d-c4de03521c30) {'updated_at': datetime.datetime(2020, 2, 19, 21, 47, 29, 134362), 'name': 'Fred the Frog', 'age': 9, 'id': '98bea5de-9cb0-4d78-8a9d-c4de03521c30', 'created_at': datetime.datetime(2020, 2, 19, 21, 47, 29, 134343)}"]

# execute tests using this command for all tests: 
$ python3 -m unittest discover tests
# test file by file by using this command: 
$ python3 -m unittest tests/test_models/test_base_model.py