org.apache.beam.sdk.transforms

Interface ExternalTransformBuilder<ConfigT,InputT extends PInput,OutputT extends POutput>

Type Parameters:

ConfigT - A configuration object which will be populated with the external configuration.

InputT - The input type of the externally configured PTransform.

OutputT - The output type of the externally configured PTransform.

All Known Implementing Classes:

DebeziumTransformRegistrar.ReadBuilder, ExternalRead.ReadBuilder, ExternalWrite.WriteBuilder, KinesisTransformRegistrar.ReadDataBuilder, KinesisTransformRegistrar.WriteBuilder, ReadBuilder, SpannerTransformRegistrar.DeleteBuilder, SpannerTransformRegistrar.InsertBuilder, SpannerTransformRegistrar.InsertOrUpdateBuilder, SpannerTransformRegistrar.ReadBuilder, SpannerTransformRegistrar.ReplaceBuilder, SpannerTransformRegistrar.UpdateBuilder, WriteBuilder

@Experimental(value=PORTABILITY)
public interface ExternalTransformBuilder<ConfigT,InputT extends PInput,OutputT extends POutput>

An interface for building a transform from an externally provided configuration.

Classes which implement this interface will be instantiated externally and require a zero-args constructor. The buildExternal method will be called with the configuration object as a parameter.

This builder needs to be registered alongside with a URN through ExternalTransformRegistrar. Note that the configuration requires setters for all configuration parameters, e.g. if there is a parameter "start", there should be a corresponding setter "setStart".

Method Summary

Modifier and Type	Method and Description
PTransform<InputT,OutputT>	buildExternal(ConfigT configuration) Builds the transform after it has been configured.
default java.util.Optional<java.util.List<java.lang.String>>	getDependencies(ConfigT configuration, PipelineOptions options) List the dependencies needed for this transform.

Method Detail

buildExternal

PTransform<InputT,OutputT> buildExternal(ConfigT configuration)

Builds the transform after it has been configured.

getDependencies

default java.util.Optional<java.util.List<java.lang.String>> getDependencies(ConfigT configuration,
                                                                             PipelineOptions options)

List the dependencies needed for this transform. Jars from classpath are used by default when Optional.empty() is returned.