Contexts and Results

Contexts and Results

The built-in context and result types. Contexts parameterize workflow steps; results carry their output. Both are BaseModel subclasses, so they validate and serialize like any config. See Defining Workflows for usage.

Contexts

All contexts derive from ContextBase and are frozen and hashable so they can serve as cache keys.

Type	Fields	Notes
NullContext	none	For steps with no runtime parameters.
GenericContext[T]	value: T	Holds an arbitrary (optionally typed) value.
DateContext	date	Single date.
DatetimeContext	dt	Single datetime.
DateRangeContext	start_date, end_date	A date range.
VersionedDateContext	date, entry_time_cutoff	Date with an as-of cutoff.
UniverseContext	universe	A named universe.
UniverseDateContext	universe, date	Universe plus date.
ModelDateContext	mode, date	Model name plus date.

Validation conveniences

NullContext validates from None or an empty container:

NullContext.model_validate(None)   # NullContext()
NullContext.model_validate([])     # NullContext()

GenericContext[T] coerces its value to T:

GenericContext[str].model_validate(100)   # GenericContext[str](value='100')

Date-based contexts accept strings and tuples, including relative offsets (handy from the command line):

DateContext.model_validate("2025-01-01")        # explicit date
DateContext.model_validate("0d")                # today
DateRangeContext.model_validate(("-7d", "0d"))  # last 7 days through today

Results

All results derive from ResultBase.

Type	Holds
GenericResult[T]	An arbitrary (optionally typed) value.
PandasResult	A pandas DataFrame.
NDArrayResult	A NumPy array.
ArrowResult	A PyArrow table.
XArrayResult	An xarray structure.
NarwhalsFrameResult	A dataframe via Narwhals, for cross-library compatibility.

GenericResult

Holds anything, with optional generic typing and boilerplate-reducing validation:

GenericResult(value={"x": "foo", "y": 5.0})     # any value
GenericResult[str](value="Any string")          # typed
GenericResult.model_validate("Any string")      # bare value validated into the wrapper

Custom results

Define a schema by subclassing ResultBase:

from ccflow import ResultBase

class MyResult(ResultBase):
    x: str
    y: float

See also

• Core Types — ContextBase, ResultBase, and the surrounding machinery.
• Defining Workflows — contexts and results in a running workflow.