Skip to main content

Documentation Index

Fetch the complete documentation index at: https://mintlify.com/Indroic/HexCore/llms.txt

Use this file to discover all available pages before exploring further.

A Command represents an intent to change state. In CQRS, write-side messages are modelled as commands: each command has a clear name, carries all the data needed to perform the operation, and is dispatched to exactly one handler. HexCore’s Command base class enforces immutability (frozen=True) so command objects cannot be accidentally mutated after construction, making them safe to pass through middleware pipelines and serialize for background queues. 
from hexcore.domain.cqrs.commands import Command

​
Class definition

class Command(BaseModel):
    model_config = ConfigDict(
        frozen=True,
        from_attributes=True,
    )

​
Fields

​
command_id
UUID
default:"uuid4()"
A unique identifier auto-generated for every command instance. Useful for idempotency checks, distributed tracing, and deduplication in task queues.
​
timestamp
datetime
UTC creation time of the command, set automatically via datetime.now(UTC). Useful for auditing and ordering in async systems.

​
Model configuration

OptionValueEffect
frozenTrueAll fields become read-only after instantiation. Attempts to mutate a field raise a ValidationError. The command is also hashable, enabling use in sets or as dict keys.
from_attributesTrueAllows constructing a command from ORM objects or other attribute-bearing objects via Command.model_validate(obj).

​
Type aliases

TCommand = TypeVar("TCommand", bound=Command)
TCommandResult = TypeVar("TCommandResult")
​
TCommand
TypeVar
A type variable bound to Command. Use this when declaring a generic handler to constrain the handler to a specific command subclass.
​
TCommandResult
TypeVar
An unconstrained type variable for the return value of a command handler. Use None for fire-and-forget commands that produce no meaningful result.

​
Usage example

from uuid import UUID
from hexcore.domain.cqrs.commands import Command

class CreateOrderCommand(Command):
    customer_id: UUID
    items: list[dict]
    shipping_address: str
Because commands are frozen Pydantic models, they are automatically JSON-serializable via .model_dump() and .model_dump_json(). This makes them straightforward to enqueue in background task systems such as Celery, ARQ, or Dramatiq when decorated with @background_command.

Build docs developers (and LLMs) love

Get started for freeTalk to us