Foundations > Higher-level programming > AirBnB clone

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This is the first step towards building your first full web application: the AirBnB clone. This first step is very important because you will use what you build during this project with all other following projects: HTML/CSS templating, database storage, API, front-end integration…

Each task is linked and will help you to:

• put in place a parent class (called [ BaseModel ]) to take care of the initialization, serialization and deserialization of your future instances
• create a simple flow of serialization/deserialization: Instance <-> Dictionary <-> JSON string <-> file
• create all classes used for AirBnB ([ User, State, City, Place… ]) that inherit from [ BaseModel ]
• create the first abstracted storage engine of the project: File storage.
• create all unittests to validate all our classes and storage engine

Do you remember the Shell? It’s exactly the same but limited to a specific use-case. In our case, we want to be able to manage the objects of our project:

• Create a new object (ex: a new User or a new Place)
• Retrieve an object from a file, a database etc…
• Do operations on objects (count, compute stats, etc…)
• Update attributes of an object
• Destroy an object

All tests should also pass in non-interactive mode: $ echo "python3 -m unittest discover tests" | bash

Your shell should work like this in interactive mode:

$ ./console.py
(hbnb)help

Documented commands (type help <topic>):
========================================
EOF  all  count  create  destroy  help  nothing  quit  show  update

(hbnb)
(hbnb) 
(hbnb)quit
$ 

But also in non-interactive mode: (like the Shell project in C)

$ echo "help" | ./console.py
(hbnb)

Documented commands (type help <topic>):
========================================
EOF  help  quit
(hbnb) 
$
$ cat test_help
help
$
$ cat test_help | ./console.py
(hbnb)

Documented commands (type help <topic>):
========================================
EOF  all  count  create  destroy  help  nothing  quit  show  update
(hbnb) 
$

All tests should also pass in non-interactive mode:

$ echo "python3 -m unittest discover tests" | bash

.......
----------------------------------------------------------------------
Ran 52 tests in 0.021s

OK

Write a README.md:

• description of the project
• description of the command interpreter: how to start it how to use it
• You should have an AUTHORS file at the root of your repository, listing all individuals having contributed content to the repository. For format, reference Docker’s AUTHORS page
• You should use branches and pull requests on GitHub - it will help you as team to organize your work

Write beautiful code that passes the PEP8 checks.

All your files, classes, functions must be tested with unit tests

python3 -m unittest discover tests Warning: Unit tests must also pass in non-interactive mode: echo "python3 -m unittest discover tests" | bash

Write a class BaseModel that defines all common attributes/methods for other classes:

• [ models/base_model.py ]
• Public instance attributes: id: string - assign with an uuid when an instance is created: you can use uuid.uuid4() to generate unique id but don’t forget to convert to a string the goal is to have unique id for each BaseModel [ created_at: ] datetime - assign with the current datetime when an instance is created [ updated_at: ] datetime - assign with the current datetime when an instance is created and it will be updated every time you change your object
• str: should print: [] (<self.id>) <self.dict>
• Public instance methods: [ save(self): ] updates the public instance attribute updated_at with the current datetime [ to_dict(self): ] returns a dictionary containing all keys/values of dict of the instance: by using self.dict, only instance attributes set will be returned a key class must be added to this dictionary with the class name of the object created_at and updated_at must be converted to string object in ISO format: format: %Y-%m-%dT%H:%M:%S.%f (ex: 2017-06-14T22:31:03.285259) you can use isoformat() of datetime object This method will be the first piece of the serialization/deserialization process: create a dictionary representation with “simple object type” of our BaseModel

you will have a complete web application composed by:

• A command interpreter to manipulate data without a visual interface, like in a Shell (perfect for development and debugging)
• A website (the front-end) that shows the final product to everybody: static and dynamic
• A database or files that store data (data = objects)
• An API that provides a communication interface between the front-end and your data (retrieve, create, delete, update them)

./test_base_model.py

Previously we created a method to generate a dictionary representation of an instance (method to_dict()). Now it’s time to re-create an instance with this dictionary representation.

<class 'BaseModel'> -> to_dict() -> <class 'dict'> -> <class 'BaseModel'>

./test_base_model_dict.py

Now we can recreate a BaseModel from another one by using a dictionary representation:

<class 'BaseModel'> -> to_dict() -> <class 'dict'> -> <class 'BaseModel'> 

Now the flow of serialization-deserialization will be:

<class 'BaseModel'> -> to_dict() -> <class 'dict'> -> JSON dump -> <class 'str'> -> FILE -> <class 'str'> -> JSON load -> <class 'dict'> -> <class 'BaseModel'>

./test_save_reload_base_model.py

Write a program called console.py that contains the entry point of the command interpreter:

• You must use the module cmd
• Your class definition must be: class HBNBCommand(cmd.Cmd):
• Your command interpreter should implement: [ quit ] and [ EOF ] to exit the program [ help ] (this action is provided by default by [ cmd ] but you should keep it updated and documented as you work through tasks) a custom prompt: [ (hbnb) ] an empty line + [ ENTER ] shouldn’t execute anything
• Your code should not be executed when imported

./console.py

$ ./console.py
(hbnb) help

Documented commands (type help <topic>):
========================================
EOF  help  quit

(hbnb) 
(hbnb) help quit
Quit command to exit the program

(hbnb) 
(hbnb) 
(hbnb) quit 
$

Update your command interpreter (console.py) to have these commands:

• [create] : Creates a new instance of BaseModel, saves it (to the JSON file) and prints the id. Ex: $ create BaseModel If the class name is missing, print ** class name missing ** (ex: $ create) If the class name doesn’t exist, print ** class doesn't exist ** (ex: $ create MyModel)
• [show] : Prints the string representation of an instance based on the class name and id. Ex: $ show BaseModel 1234-1234-1234. If the class name is missing, print ** class name missing ** (ex: $ show) If the class name doesn’t exist, print ** class doesn't exist ** (ex: $ show MyModel) If the id is missing, print ** instance id missing ** (ex: $ show BaseModel) If the instance of the class name doesn’t exist for the id, print ** no instance found ** (ex: $ show BaseModel 121212)
• [destroy] : Deletes an instance based on the class name and id (save the change into the JSON file). Ex: $ destroy BaseModel 1234-1234-1234. If the class name is missing, print ** class name missing ** (ex: $ destroy) If the class name doesn’t exist, print ** class doesn't exist ** (ex:$ destroy MyModel) If the id is missing, print ** instance id missing ** (ex: $ destroy BaseModel) If the instance of the class name doesn’t exist for the id, print ** no instance found ** (ex: $ destroy BaseModel 121212)
• [all] : Prints all string representation of all instances based or not on the class name. Ex: $ all BaseModel or $ all. The printed result must be a list of strings (like the example below) If the class name doesn’t exist, print ** class doesn't exist ** (ex: $ all MyModel)
• [update] : Updates an instance based on the class name and id by adding or updating attribute (save the change into the JSON file). Ex: $ update BaseModel 1234-1234-1234 email "[email protected]". Usage: update "" If the class name is missing, print ** class name missing ** (ex: $ update) If the class name doesn’t exist, print ** class doesn't exist ** (ex: $ update MyModel) If the id is missing, print ** instance id missing ** (ex: $ update BaseModel) If the instance of the class name doesn’t exist for the id, print ** no instance found ** (ex: $ update BaseModel 121212) If the attribute name is missing, print ** attribute name missing ** (ex: $ update BaseModel existing-id) If the value for the attribute name doesn’t exist, print ** value missing ** (ex: $ update BaseModel existing-id first_name) All other arguments should not be used (Ex: $ update BaseModel 1234-1234-1234 email "[email protected]" first_name "Betty" = $ update BaseModel 1234-1234-1234 email "[email protected]") id, created_at and updated_at cant’ be updated. You can assume they won’t be passed in the update command

./console.py

(hbnb) all MyModel
** class doesn't exist **
(hbnb) show BaseModel
** instance id missing **
(hbnb) show BaseModel Holberton
** no instance found **
(hbnb) create BaseModel
49faff9a-6318-451f-87b6-910505c55907
(hbnb) all BaseModel
...
show BaseModel 49faff9a-6318-451f-87b6-910505c55907
...
(hbnb) destroy
** class name missing **
(hbnb) update BaseModel 49faff9a-6318-451f-87b6-910505c55907 first_name "Betty"
(hbnb) show BaseModel 49faff9a-6318-451f-87b6-910505c55907
...
(hbnb) create BaseModel
2dd6ef5c-467c-4f82-9521-a772ea7d84e9
(hbnb) all BaseModel
...
(hbnb) destroy BaseModel 49faff9a-6318-451f-87b6-910505c55907
(hbnb) show BaseModel 49faff9a-6318-451f-87b6-910505c55907
** no instance found **
(hbnb)

Write a class User that inherits from BaseModel:

• models/user.py
• Public class attributes: email: string - empty string password: string - empty string first_name: string - empty string last_name: string - empty string Update your command interpreter (console.py) to allow show, create, destroy, update and all used with User.

cat file.json ; echo "" ./test_save_reload_user.py

Write all those classes that inherit from BaseModel:

• State (models/state.py): Public class attributes: name: string - empty string
• City (models/city.py): Public class attributes: state_id: string - empty string: it will be the State.id name: string - empty string
• Amenity (models/amenity.py): Public class attributes: name: string - empty string
• Place (models/place.py): Public class attributes: city_id: string - empty string: it will be the City.id user_id: string - empty string: it will be the User.id name: string - empty string description: string - empty string number_rooms: integer - 0 number_bathrooms: integer - 0 max_guest: integer - 0 price_by_night: integer - 0 latitude: float - 0.0 longitude: float - 0.0 amenity_ids: list of string - empty list: it will be the list of Amenity.id later
• Review (models/review.py): Public class attributes: place_id: string - empty string: it will be the Place.id user_id: string - empty string: it will be the User.id text: string - empty string

Update FileStorage to manage correctly serialization and deserialization of all our new classes: Place, State, City, Amenity and Review Update your command interpreter (console.py) to allow those actions: show, create, destroy, update and all with all classes created previously.

Update your command interpreter (console.py) to retrieve all instances of a class by using: .all().

$ ./console.py (hbnb) User.all()

Update your command interpreter (console.py) to retrieve the number of instances of a class: .count(). $ ./console.py (hbnb) User.count() 2 (hbnb)

Update your command interpreter (console.py) to retrieve an instance based on its ID: .show(). Errors management must be the same as previously. $ ./console.py (hbnb) User.show("246c227a-d5c1-403d-9bc7-6a47bb9f0f68") (hbnb) User.show("Holberton") ** no instance found ** (hbnb)

Update your command interpreter (console.py) to destroy an instance based on his ID: .destroy(). Errors management must be the same as previously $ ./console.py (hbnb) User.count() 2 (hbnb) User.destroy("246c227a-d5c1-403d-9bc7-6a47bb9f0f68") (hbnb) User.count() 1 (hbnb) User.destroy("Holberton") ** no instance found ** (hbnb)

Update your command interpreter (console.py) to update an instance based on his ID: .update(, , ). Errors management must be the same as previously. ./console.py (hbnb) User.show("38f22813-2753-4d42-b37c-57a17f1e4f88") (hbnb) (hbnb) User.update("38f22813-2753-4d42-b37c-57a17f1e4f88", "first_name", "John") (hbnb) User.update("38f22813-2753-4d42-b37c-57a17f1e4f88", "age", 89) (hbnb) (hbnb) User.show("38f22813-2753-4d42-b37c-57a17f1e4f88")

Update your command interpreter (console.py) to update an instance based on his ID with a dictionary: .update(, ).

Errors management must be the same as previously. ./console.py (hbnb) User.show("38f22813-2753-4d42-b37c-57a17f1e4f88") (hbnb) (hbnb) User.update("38f22813-2753-4d42-b37c-57a17f1e4f88", "first_name", "John") (hbnb) User.update("38f22813-2753-4d42-b37c-57a17f1e4f88", "age", 89) (hbnb) (hbnb) User.show("38f22813-2753-4d42-b37c-57a17f1e4f88")

Contributors:

1. Agboola Olawale
2. Godwin Williams ..........................................................................................................................