SerializationMixin

The SerializationMixin class provides methods for serializing and deserializing SQLAlchemy models.

It uses the InspectionMixin class functionality.

Table of Contents

• SerializationMixin
• Serialization
  • to_dict
  • to_json
• Deserialization
  • from_dict
  • from_json

Serialization

to_dict

def to_dict(
    nested: bool = False,
    hybrid_attributes: bool = False,
    exclude: list[str] | None = None,
    nested_exclude: list[str] | None = None,
)

Serializes the model to a dictionary.

Parameters:

• nested: Set to True to include nested relationships' data, by default False.
• hybrid_attributes: Set to True to include hybrid attributes, by default False.
• exclude: Exclude specific attributes from the result, by default None.

Returns:

• dict[str, Any]: Serialized model.

Example:

user = await User.get(id=1)
user.to_dict()
# {'id': 1, 'username': 'user1', 'name': 'John', 'age': 30, ...}
user.to_dict(nested=True)
# {'id': 1, 'username': 'user1', 'name': 'John', 'age': 30, 'posts': [...], ...}
user.to_dict(hybrid_attributes=True)
# {'id': 1, 'username': 'user1', 'name': 'John', 'age': 30, 'posts_count': 3, ...}
user.to_dict(exclude=['id', 'username'])
# {'name': 'John', 'age': 30, ...}

to_json

def to_json(
    nested: bool = False,
    hybrid_attributes: bool = False,
    exclude: list[str] | None = None,
    nested_exclude: list[str] | None = None,
    ensure_ascii: bool = False,
    indent: int | str | None = None,
    sort_keys: bool = False
)

Serializes the model to JSON.

Calls the Self.to_dict method and dumps it with json.dumps.

Parameters:

• nested: Set to True to include nested relationships' data, by default False.
• hybrid_attributes: Set to True to include hybrid attributes, by default False.
• exclude: Exclude specific attributes from the result, by default None.
• ensure_ascii: If False, then the return value can contain non-ASCII characters if they appear in strings contained in obj. Otherwise, all such characters are escaped in JSON strings, by default False.
• indent: If indent is a non-negative integer, then JSON array elements and object members will be pretty-printed with that indent level. An indent level of 0 will only insert newlines. None is the most compact representation, by default None.
• sort_keys: Sort dictionary keys, by default False.

Returns:

• str: Serialized model.

Example:

user = await User.get(id=1)
user.to_json()
# {"id": 1, "username": "user1", "name": "John", "age": 30, ...}
user.to_json(nested=True)
# {"id": 1, "username": "user1", "name": "John", "age": 30, "posts": [...], ...}
user.to_json(hybrid_attributes=True)
# {"id": 1, "username": "user1", "name": "John", "age": 30, "posts_count": 3, ...}
user.to_json(exclude=['id', 'username'])
# {"name": "John", "age": 30, ...}

Deserialization

from_dict

def from_dict(
    data: dict[str, Any] | list[dict[str, Any]],
    exclude: list[str] | None = None,
    nested_exclude: list[str] | None = None
)

Deserializes a dictionary to the model.

Sets the attributes of the model with the values of the dictionary.

Parameters:

• data: Data to deserialize.
• exclude: Exclude specific keys from the dictionary, by default None.

Returns:

• Self | list[Self]: Deserialized model or models.

Raises:

• TypeError: If the data is not a dictionary or list of dictionaries.
• KeyError: If attribute doesn't exist.

Example:

user = await User.from_dict({'name': 'John', 'age': 30})
user.to_dict()
# {'name': 'John', 'age': 30, ...}
users = await User.from_dict([{'name': 'John', 'age': 30}, {'name': 'Jane', 'age': 25}])
users[0].to_dict()
# {'name': 'John', 'age': 30, ...}
users[1].to_dict()
# {'name': 'Jane', 'age': 25, ...}

from_json

def from_json(
    json_string: str,
    exclude: list[str] | None = None,
    nested_exclude: list[str] | None = None
)

Deserializes a JSON string to the model.

Calls the json.loads method and sets the attributes of the model with the values of the JSON object using the from_dict method.

Parameters:

• json_string: JSON string.
• exclude: Exclude specific keys from the dictionary, by default None.

Returns:

• Self | list[Self]: Deserialized model or models.

Example:

user = await User.from_json('{"name": "John", "age": 30}')
user.to_dict()
# {'name': 'John', 'age': 30, ...}
users = await User.from_json('[{"name": "John", "age": 30}, {"name": "Jane", "age": 25}]')
users[0].to_dict()
# {'name': 'John', 'age': 30, ...}
users[1].to_dict()
# {'name': 'Jane', 'age': 25, ...}