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Storage models

The SQLAlchemy table definitions used by SQLAlchemyDB.

hololinked.storage.models.SerializedProperty

Bases: MappedAsDataclass, ThingTableBase

Represents a serialized property of a Thing instance stored in the database.

Property Serialized is done, providing unified version for SQLite and other relational tables. Anyway while sending in the wire, the value is serialized to bytes, so when preserialized, the bytes are stored directly. A performance problem is not expected.

Source code in repo/hololinked/hololinked/storage/models.py 
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class SerializedProperty(MappedAsDataclass, ThingTableBase):
    """
    Represents a serialized property of a `Thing` instance stored in the database.

    Property Serialized is done, providing unified version for SQLite and other relational tables.
    Anyway while sending in the wire, the value is serialized to bytes, so when preserialized, the bytes
    are stored directly. A performance problem is not expected.
    """

    __tablename__ = "properties"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    name: Mapped[str] = mapped_column(String, unique=True, nullable=False)
    serialized_value: Mapped[bytes] = mapped_column(LargeBinary, nullable=False)
    thing_id: Mapped[str] = mapped_column(String)
    thing_class: Mapped[str] = mapped_column(String)
    created_at: Mapped[str] = mapped_column(String)
    updated_at: Mapped[str] = mapped_column(String)
    content_type: Mapped[str] = mapped_column(String, nullable=False, default="application/json")

hololinked.storage.models.ThingInformation

Bases: MappedAsDataclass, ThingTableBase

Stores information about the Thing instance itself.

Useful metadata which may be later populated in a GUI or client applications need to go here.

Source code in repo/hololinked/hololinked/storage/models.py 
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class ThingInformation(MappedAsDataclass, ThingTableBase):
    """
    Stores information about the Thing instance itself.

    Useful metadata which may be later populated in a GUI or client applications need to go here.
    """

    __tablename__ = "things"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    thing_id: Mapped[str] = mapped_column(String, unique=True, nullable=False)
    thing_class: Mapped[str] = mapped_column(String, nullable=False)
    script: Mapped[str] = mapped_column(String)
    init_kwargs: Mapped[JSONSerializable] = mapped_column(JSON)
    server_id: Mapped[str] = mapped_column(String)

    def json(self) -> dict[str, Any]:
        """
        JSON-serializable dictionary representation of the Thing information.

        Returns
        -------
        dict[str, Any]
        """
        return asdict(self)

Attributes

id class-attribute instance-attribute 

id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)

thing_id class-attribute instance-attribute 

thing_id: Mapped[str] = mapped_column(String, unique=True, nullable=False)

thing_class class-attribute instance-attribute 

thing_class: Mapped[str] = mapped_column(String, nullable=False)

script class-attribute instance-attribute 

script: Mapped[str] = mapped_column(String)

init_kwargs class-attribute instance-attribute 

init_kwargs: Mapped[JSONSerializable] = mapped_column(JSON)

server_id class-attribute instance-attribute 

server_id: Mapped[str] = mapped_column(String)

Functions

json 

json() -> dict[str, Any]

JSON-serializable dictionary representation of the Thing information.

Returns:

Type Description
dict[str, Any]
Source code in repo/hololinked/hololinked/storage/models.py 
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def json(self) -> dict[str, Any]:
    """
    JSON-serializable dictionary representation of the Thing information.

    Returns
    -------
    dict[str, Any]
    """
    return asdict(self)

hololinked.storage.models.DeserializedProperty dataclass

Property with deserialized value after fetching from database.

Source code in repo/hololinked/hololinked/storage/models.py 
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@dataclass
class DeserializedProperty:  # not part of database
    """Property with deserialized value after fetching from database."""

    thing_id: str
    name: str
    value: Any
    created_at: str
    updated_at: str

Attributes

thing_id instance-attribute 

thing_id: str

name instance-attribute 

name: str

value instance-attribute 

value: Any

created_at instance-attribute 

created_at: str

updated_at instance-attribute 

updated_at: str

hololinked.storage.models.ThingTableBase

Bases: DeclarativeBase

SQLAlchemy base table for all Thing related tables.

Source code in repo/hololinked/hololinked/storage/models.py 
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class ThingTableBase(DeclarativeBase):
    """SQLAlchemy base table for all `Thing` related tables."""

    pass