Hi Filipe, The problem your encountering most likely stems from the fact that Flink serializes all operators before running them in the (local) cluster. During this process all outside references inside your sink are lost.
In the thread you've found are two solutions for this: Use the collect sink: contrib/streaming/DataStreamUtils.java <https://github.com/apache/flink/blob/master/flink-contrib/flink-streaming-contrib/src/main/java/org/apache/flink/contrib/streaming/DataStreamUtils.java> which provides you with an iterator containing the results. I've no idea if this works with the current version of Flink or even with the scala api DataStream class. And the solution from nick who directly uses a local static variable for the results: https://gist.github.com/ndimiduk/5f3b4757eb772feed6e6 <https://gist.github.com/ndimiduk/5f3b4757eb772feed6e6> you have to set the parallelism to 1 as you've discovered. (Haven't tested this either) The third solution would be of course to use flink-spector, which takes care of these issues. But I have currently no time to finish support for scala. You can find an example and the current state here: [DataStreamSpec]https://github.com/lofifnc/flink-spector/blob/scala_api/flinkspector-datastream-scala_2.11/src/test/scala/org/flinkspector/scala/datastream/DataStreamSpec.scala. (This is works but has also not really been tested) Best, Alex -- View this message in context: http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/Unit-testing-support-for-flink-application-tp4130p4189.html Sent from the Apache Flink User Mailing List archive. mailing list archive at Nabble.com.
