[SAMZA-681] Create a unit test harness to easily test samza tasks

• Type: Test
• Status: Patch Available
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 0.9.0
• Component/s: test
• Assignee: Jose Martinez
• Reporter: Luis De Pombo
• Created: 16/May/15 00:49
• Updated: 29/Sep/16 22:18

Description

We don't have a standardized test framework for unit testing samza tasks. Currently, in order to test the proper functionality of a task we have to bring up the system (kafka) and its dependencies (zk).

Goals:

• The harness should abstract several notions around the system and its partitions, without mocking them, and hold task context and state in memory.
• The harness should let you inject several <key,value> pairs that would normally be passed in by the `SystemStream` provided in `tasks.input`.
• The same harness should offer an interface to visualize all the corresponding <key,value> pairs collected in the message `Collector`, which are the output of the `process`ed or `window`ed input <key,value> pairs previously injected.