org.apache.beam.sdk.io.gcp.spanner.changestreams.dao

Class ChangeStreamDao

java.lang.Object

org.apache.beam.sdk.io.gcp.spanner.changestreams.dao.ChangeStreamDao

public class ChangeStreamDao
extends java.lang.Object

Responsible for making change stream queries for a given partition. The result will be given back as a ResultSet, which can be consumed until the stream is finished.

Method Summary

Modifier and Type	Method and Description
ChangeStreamResultSet	changeStreamQuery(java.lang.String partitionToken, com.google.cloud.Timestamp startTimestamp, com.google.cloud.Timestamp endTimestamp, long heartbeatMillis) Performs a change stream query.

Methods inherited from class java.lang.Object

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

Method Detail

changeStreamQuery

public ChangeStreamResultSet changeStreamQuery(java.lang.String partitionToken,
                                               com.google.cloud.Timestamp startTimestamp,
                                               @Nullable
                                               com.google.cloud.Timestamp endTimestamp,
                                               long heartbeatMillis)

Performs a change stream query. If the partition token given is the initial partition null will be used in the query instead. The change stream query will be tagged as following: "action=<REQUEST_TAG>, job=<jobName>". The result will be given as a ChangeStreamResultSet which can be consumed as a stream, yielding records until no more are available for the query made. Note that one needs to call ChangeStreamResultSet.next() to initiate the change stream query.

Parameters:

partitionToken - the unique partition token to be queried. If InitialPartition.PARTITION_TOKEN is given, null will be used in the change stream query instead.

startTimestamp - the inclusive start time for the change stream query

endTimestamp - the inclusive end time for the change stream query. Null can be provided to indicate no end time is available

heartbeatMillis - the number of milliseconds after the stream is idle, which a heartbeat record will be emitted in the change stream query

Returns:

a ChangeStreamResultSet that will produce a stream of records for the change stream query