file_storage.py

#!/usr/bin/python3

import json
import os
from models.base_model import BaseModel
from models.user import User
from models.state import State
from models.city import City
from models.place import Place
from models.amenity import Amenity
from models.review import Review


class FileStorage:
    """
    Defines FileStorage class

    Attributes:
        __file_path = string, private, file name
        __objects = Dictionary, empty but will grow with value
        __classes
    """
    __file_path = "file.json"
    __objects = {}
    __classes = {
            "BaseModel": BaseModel,
            "User": User,
            "State": State,
            "City": City,
            "Place": Place,
            "Amenity": Amenity,
            "Review": Review
            }

    def __init__(self):
        """Initialization"""
        pass

    def all(self):
        """
        returns the dictionary __objects
        """
        # return (FileStorage.__objects)
        return (self.__objects)

    def new(self, obj):
        """
        sets in __objects the obj with key <obj class name>.id
        """
        my_key = ("{}.{}".format(obj.__class__.__name__, obj.id))
        # FileStorage.__objects[my_key] = obj
        self.__objects[my_key] = obj

    def save(self):
        """serializes __objects to the JSON file (path: __file_path)"""
        my_temp_dict = {}
        for key, value in FileStorage.__objects.items():
            my_temp_dict[key] = value.to_dict()

        with open(FileStorage.__file_path, "w", encoding="utf-8") as myFile:
            json.dump(my_temp_dict, myFile)
        # with open(FileStorage.__file_path, "w", encoding="utf-8") as file:
        #     dict_value = {key: value.to_dict() for key,
        #                   value in FileStorage.__objects.items()}
        #     json.dump(dict_value, file)

    def reload(self):
        """deserializes the JSON file to __objects
        (only if the JSON file (__file_path) exists; otherwise, do nothing.
        If the file doesn’t exist, no exception should be raised)"""

        # Error check when file.json does not exist.
        if os.path.exists(FileStorage.__file_path):
            # with open(self.__file_path, "r", encoding="utf-8") as myFile:
            with open(FileStorage.__file_path, "r", encoding="utf-8") as myFil:
                my_reload_dict = json.load(myFil)
                for key, value in my_reload_dict.items():
                    split_result = key.split(".")
                    class_name = split_result[0]
                    class_ID = split_result[1]
                    obj_class = FileStorage.__classes.get(class_name)
                    if obj_class is not None:
                        FileStorage.__objects[key] = obj_class(**value)