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Code ReferenceEngine Extension APIProcessor API

data_designer.engine.processing.processors.schema_transform

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Module Contents

Classes

NameDescription
SchemaTransformProcessorTransforms dataset schema using Jinja2 templates after each batch.

Functions

NameDescription
_escape_value_for_jsonEscape a value for safe embedding inside a JSON string.

Data

logger

API

1logger = getLogger(...)
 
1data_designer.engine.processing.processors.schema_transform._escape_value_for_json(value: typing.Any) -> str

Escape a value for safe embedding inside a JSON string.

Unlike prompt or expression templates (which produce plain text), schema transform templates produce JSON. Values interpolated into a JSON string must be escaped - e.g. quotes and backslashes - so the rendered output is valid JSON. We pass this as record_str_fn to also enable nested dot access, such as {{ col.sub.field }}, on deserialized JSON columns.

1class data_designer.engine.processing.processors.schema_transform.SchemaTransformProcessor(
2    config: data_designer.engine.configurable_task.TaskConfigT,
3    resource_provider: data_designer.engine.resources.resource_provider.ResourceProvider
4)

Bases: data_designer.engine.processing.ginja.environment.WithJinja2UserTemplateRendering, data_designer.engine.processing.processors.base.Processor[data_designer.config.processors.SchemaTransformProcessorConfig]

Transforms dataset schema using Jinja2 templates after each batch.

1template_as_str: str
1process_after_batch(
2    data: pandas.DataFrame,
3    *,
4    current_batch_number: int | None
5) -> pandas.DataFrame
1_transform(data: pandas.DataFrame) -> pandas.DataFrame