Cross-layer Data Flow API

Complete API reference for ExposeAs, SendTo, and Collector.

ExposeAs

Exposes ancestor fields to descendant nodes, accessible via ancestor_context.

from typing import Annotated
from sqlmodel_nexus import ExposeAs

class SprintDTO(DefineSubset):
    __subset__ = (Sprint, ("id", "name"))
    name: Annotated[str, ExposeAs('sprint_name')]

Parameters

Parameter	Type	Description
key	str	Key name in ancestor_context

Accessing in Descendants

class TaskDTO(DefineSubset):
    def post_full_title(self, ancestor_context):
        return f"{ancestor_context['sprint_name']} / {self.title}"

ancestor_context is a dict collecting all values exposed by ancestors through ExposeAs.

SendTo

Sends descendant field values to an ancestor's Collector.

from typing import Annotated
from sqlmodel_nexus import SendTo

class TaskDTO(DefineSubset):
    __subset__ = (Task, ("id", "title", "owner_id"))
    owner: Annotated[UserDTO | None, SendTo('contributors')] = None

Parameters

Parameter	Type	Description
collector_name	str	Name of the target Collector

Collector

Receives values sent by descendants via SendTo in post_* methods.

from sqlmodel_nexus import Collector

class SprintDTO(DefineSubset):
    contributors: list[UserDTO] = []

    def post_contributors(self, collector=Collector('contributors')):
        return collector.values()

Collector Methods

Method	Description
values()	Returns a list of all collected values

Parameters

Parameter	Type	Description
name	str	Collector name, matching the SendTo target name