Сделали метамодель и переопределили классы с полиморфизмом

This commit is contained in:
2026-06-03 20:00:12 +03:00
parent bd7aaa58a3
commit 9c69656554
+66 -45
View File
@@ -2,9 +2,39 @@ import sqlite3
db_name = 'mydb.db'
class BaseModel:
def __init__(self,id):
self.__id = id
class Field:
def __init__(self,name,column_type):
self.name = name
self.type = column_type
def __str__(self):
return f'{self.name}:{self.type}'
class IntegerField(Field):
def __init__(self,name):
super().__init__(name,'INTEGER')
class StringField(Field):
def __init__(self,name):
super().__init__(name,'TEXT')
class ModelMeta(type):
def __new__(cls, name, bases, attrs):
if name == 'BaseModel':
return super().__new__(cls,name,bases,attrs)
fields = dict()
for k,v in attrs.items():
if isinstance(v,Field):
fields[k] = v
attrs['_fields'] = fields
return super().__new__(cls,name,bases,attrs)
class BaseModel(metaclass=ModelMeta):
def __init__(self,**kwargs):
for k,v in kwargs.items():
setattr(self,k,v) #{'name': 'Alex'} self.name = 'Alex'
@classmethod
def get_by_id(cls,id):
@@ -24,6 +54,19 @@ class BaseModel:
def save(self):
conn = sqlite3.connect(db_name)
cursor = conn.cursor()
fields = []
values = []
for name, field in self._fields.items():
fields.append(field.name)
values.append(getattr(self,name,None))
query =f'''INSERT INTO {self.__class__.__name__.lower()}({','.join(fields)})
VALUES({','.join(['?']*len(values))})'''
print(query,values)
conn.close()
'''
property_list = [f"{k}" for k, v in self.__class__.__dict__.items() if isinstance(v, property)]
if self.__id != None:
@@ -41,42 +84,28 @@ class BaseModel:
cursor.execute(query,property_values)
conn.commit()
self.__id = cursor.lastrowid
conn.close()
'''
def validate_email(func):
def wrapper(self,*args,**kwargs):
if hasattr(self,'email'):
if '@' not in self.email:
raise ValueError('Некоректный email')
return func(self,*args,**kwargs)
return wrapper
class User(BaseModel):
def __init__(self,name,email,age,id = None):
super().__init__(id)
self.__name = name
self.__email = email
self.__age = age
id = IntegerField('id')
name = StringField('name')
age = Field('age','REAL')
email = StringField('email')
@property
def name(self):
return self.__name
@name.setter
def name(self,value):
self.__name = value
@property
def email(self):
return self.__email
@email.setter
def email(self,value):
if '@' in value:
self.__email = value
else:
raise ValueError('Не корректный адрес почты')
@property
def age(self):
return self.__age
@age.setter
def age(self,value):
if 0 <= value <= 120:
self.__age = value
else:
raise ValueError('Неправильно указан возраст')
@validate_email
def save(self):
super().save()
'''
class Product(BaseModel):
def __init__(self,name,category,price,id=None):
super().__init__(id)
@@ -92,15 +121,7 @@ class Product(BaseModel):
@property
def price(self):
return self.__price
'''
product1 = Product('Свинина, шея','Мясные продукты',250)
product1.save()
'''
user2 = User.get_by_id(9)
user2.name = 'Andrey'
user2.save()
user1 = User('Igor','igor@example.com',44)
user1 = User(name='John',age=18, email='john@example.com')
user1.save()
user1.age = 55
user1.save()
'''