org.apache.beam.sdk.io.gcp.pubsub

Class PubsubIO.Write<T>

java.lang.Object

org.apache.beam.sdk.transforms.PTransform<PCollection<T>,PDone>

org.apache.beam.sdk.io.gcp.pubsub.PubsubIO.Write<T>

All Implemented Interfaces:

java.io.Serializable, HasDisplayData

Enclosing class:

PubsubIO

public abstract static class PubsubIO.Write<T>
extends PTransform<PCollection<T>,PDone>

Implementation of PubsubIO.write().

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	PubsubIO.Write.PubsubBoundedWriter Writer to Pubsub which batches messages from bounded collections.

Field Summary

Fields inherited from class org.apache.beam.sdk.transforms.PTransform

name

Constructor Summary

Constructors

Constructor and Description
Write()

Method Summary

Modifier and Type	Method and Description
PDone	expand(PCollection<T> input) Override this method to specify how this PTransform should be expanded on the given InputT.
void	populateDisplayData(DisplayData.Builder builder) Register display data for the given transform or component.
PubsubIO.Write<T>	to(java.lang.String topic) Publishes to the specified topic.
PubsubIO.Write<T>	to(ValueProvider<java.lang.String> topic) Like topic() but with a ValueProvider.
PubsubIO.Write<T>	withIdAttribute(java.lang.String idAttribute) Writes to Pub/Sub, adding each record's unique identifier to the published messages in an attribute with the specified name.
PubsubIO.Write<T>	withMaxBatchBytesSize(int maxBatchBytesSize) Writes to Pub/Sub are limited by 10mb in general.
PubsubIO.Write<T>	withMaxBatchSize(int batchSize) Writes to Pub/Sub are batched to efficiently send data.
PubsubIO.Write<T>	withTimestampAttribute(java.lang.String timestampAttribute) Writes to Pub/Sub and adds each record's timestamp to the published messages in an attribute with the specified name.

Methods inherited from class org.apache.beam.sdk.transforms.PTransform

getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, toString, validate

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Write

public Write()

Method Detail

to

public PubsubIO.Write<T> to(java.lang.String topic)

Publishes to the specified topic.

See PubsubIO.PubsubTopic.fromPath(String) for more details on the format of the topic string.

to

public PubsubIO.Write<T> to(ValueProvider<java.lang.String> topic)

Like topic() but with a ValueProvider.

withMaxBatchSize

public PubsubIO.Write<T> withMaxBatchSize(int batchSize)

Writes to Pub/Sub are batched to efficiently send data. The value of the attribute will be a number representing the number of Pub/Sub messages to queue before sending off the bulk request. For example, if given 1000 the write sink will wait until 1000 messages have been received, or the pipeline has finished, whichever is first.

Pub/Sub has a limitation of 10mb per individual request/batch. This attribute was requested dynamic to allow larger Pub/Sub messages to be sent using this source. Thus allowing customizable batches and control of number of events before the 10mb size limit is hit.

withMaxBatchBytesSize

public PubsubIO.Write<T> withMaxBatchBytesSize(int maxBatchBytesSize)

Writes to Pub/Sub are limited by 10mb in general. This attribute controls the maximum allowed bytes to be sent to Pub/Sub in a single batched message.

withTimestampAttribute

public PubsubIO.Write<T> withTimestampAttribute(java.lang.String timestampAttribute)

Writes to Pub/Sub and adds each record's timestamp to the published messages in an attribute with the specified name. The value of the attribute will be a number representing the number of milliseconds since the Unix epoch. For example, if using the Joda time classes, Instant.Instant(long) can be used to parse this value.

If the output from this sink is being read by another Beam pipeline, then PubsubIO.Read.withTimestampAttribute(String) can be used to ensure the other source reads these timestamps from the appropriate attribute.

withIdAttribute

public PubsubIO.Write<T> withIdAttribute(java.lang.String idAttribute)

Writes to Pub/Sub, adding each record's unique identifier to the published messages in an attribute with the specified name. The value of the attribute is an opaque string.

If the the output from this sink is being read by another Beam pipeline, then PubsubIO.Read.withIdAttribute(String) can be used to ensure that* the other source reads these unique identifiers from the appropriate attribute.

expand

public PDone expand(PCollection<T> input)

Description copied from class: PTransform

Override this method to specify how this PTransform should be expanded on the given InputT.

NOTE: This method should not be called directly. Instead apply the PTransform should be applied to the InputT using the apply method.

Composite transforms, which are defined in terms of other transforms, should return the output of one of the composed transforms. Non-composite transforms, which do not apply any transforms internally, should return a new unbound output and register evaluators (via backend-specific registration methods).

Specified by:

expand in class PTransform<PCollection<T>,PDone>

populateDisplayData

public void populateDisplayData(DisplayData.Builder builder)

Description copied from class: PTransform

Register display data for the given transform or component.

populateDisplayData(DisplayData.Builder) is invoked by Pipeline runners to collect display data via DisplayData.from(HasDisplayData). Implementations may call super.populateDisplayData(builder) in order to register display data in the current namespace, but should otherwise use subcomponent.populateDisplayData(builder) to use the namespace of the subcomponent.

By default, does not register any display data. Implementors may override this method to provide their own display data.

Specified by:

populateDisplayData in interface HasDisplayData

Overrides:

populateDisplayData in class PTransform<PCollection<T>,PDone>

Parameters:

builder - The builder to populate with display data.

See Also:

HasDisplayData