spark-sql-streaming-ContinuousReadSupport.adoc

ContinuousReadSupport Contract — Data Sources with ContinuousReaders

ContinuousReadSupport is the abstraction of data sources with a ContinuousReader in Continuous Stream Processing.

ContinuousReadSupport defines a single createContinuousReader method to create a ContinuousReader.

ContinuousReader createContinuousReader(
  Optional<StructType> schema,
  String checkpointLocation,
  DataSourceOptions options)

createContinuousReader is used when:

• ContinuousExecution is requested to run a streaming query (and finds ContinuousExecutionRelations in the analyzed logical plan)

• DataStreamReader is requested to create a streaming query for a ContinuousReadSupport data source

Table 1. ContinuousReadSupports

ContinuousReadSupport	Description
ContinuousMemoryStream
KafkaSourceProvider
RateStreamProvider
TextSocketSourceProvider