Random message ordering about flink-spector HOT 1 CLOSED

Hi,

This is an interesting case. The philosophy of flinkspector was always to simulate an environment as close to the actual cluster. Which is why for example tests run at default at a parallelism of 2. This approach is of course debatable, but the idea is to provide almost lightweight integration tests. Based on our experience this allows you to find certain errors, which would otherwise not be discovered until running your program on an actual cluster.

In your case you have two streams. And you would like to be able to define a order of messages across these two streams. And this order should be preserved until they arrive at a certain operator. With the current design of the framework, which just runs a local cluster and injects messages, I don't have enough control to achieve this in a satisfying way.

If you just wan't to unit test your RichCoFlatMapFunction I would suggest using a Test Harness:
https://github.com/apache/flink/blob/master/flink-streaming-java/src/test/java/org/apache/flink/streaming/util/TwoInputStreamOperatorTestHarness.java

This has also been our approach. Write tests for individual operators. And then test your operators in conjunction using flinkspector.

I hope this helps.

from flink-spector.