result
Result for the generic en-face lesion calculation step (v1).
Classes
LesionCalculationResult
class LesionCalculationResult(**data: Any):Result of a lesion calculation task.
records_stored reports how many per-file area rows were persisted to the
lesion_calculation cache table. The metrics themselves are not returned
in-memory: this step runs in background mode, where an in-memory result does
not cross the phase boundary, so a downstream step reads the rows via the
<step_name>.cache accessor (or records in the same process).
records_stored means two different things depending on which path the
task took: on the compute path it is the number of rows persisted by
this invocation (len(records) in persist_lesion_metrics); on the
read-before-compute early return, where nothing was stale, it is instead
the total row count of the step's own partition (own_accessor.count()
in lesion_calculation_task) — there being no new rows to report, the
field falls back to describing what is already there.
Create a new model by parsing and validating input data from keyword arguments.
Raises [ValidationError][pydantic_core.ValidationError] if the input data cannot be
validated to form a valid model.
self is explicitly positional-only to allow self as a field name.
Ancestors
Variables
- static
model_config
cache : CacheAccessor | None- Return theCacheAccessorfor reading this result in a DAG pipeline.
-
records : pandas.core.frame.DataFrame- Retrieve this result's rows as a DataFrame.The DataFrame is fetched from the cache on each access — it is not stored in the result object, allowing lazy access to large datasets without materialising them in memory until needed.
Returns: A
pandas.DataFramewith one row per cached record.Raises: RuntimeError: If no accessor is attached (e.g. the result was serialised across a Prefect task boundary). In a DAG pipeline use
<step_name>.cacheinstead.
Static methods
from_accessor
def from_accessor( accessor: CacheAccessor, *, records_stored: int | None = None,) ‑> Self:Inherited from:
CacheBackedResult.from_accessor :
Build a result carrying accessor, in one call rather than two.
_accessor is a PrivateAttr, so it cannot be passed to the
constructor and every producer would otherwise construct the result and
then reach in to attach the accessor. That two-step is the shape this
replaces.
Arguments
accessor: TheCacheAccessorbacking<step>.cache, scoped to the partition this result stands for.records_stored: Rows this result stands for. Defaults toaccessor.count()— the whole partition — which is what a step that persisted nothing this run reports. A step that wrote rows passes what it wrote; see the field's docstring for why the two are not interchangeable.
Returns An instance of the calling subclass, with the accessor attached.
Methods
model_post_init
def model_post_init(self: BaseModel, context: Any, /) ‑> None:Inherited from:
CacheBackedResult.model_post_init :
This function is meant to behave like a BaseModel method to initialise private attributes.
It takes context as an argument since that's what pydantic-core passes when calling it.
Arguments
self: The BaseModel instance.context: The context.