BuildTestReadMessages builds test isb.ReadMessage which can be used for testing.

BuildTestReadMessagesIntOffset builds test isb.ReadMessage which can be used for testing.

BuildTestWindowRequests builds test window.TimedWindowRequest which can be used for testing.

BuildTestWriteMessages builds test isb.Message which can be used for testing.

CopyUDFTestApply applies a copy UDF that simply copies the input to output.

ReadMessagesLen is used to test the length of the messages read as they arrive on the stream If a stream already has 5 elements which have been read and then we add another set of elements of 10 the total number would be 15.

PayloadForTest is a dummy payload for testing.