[SAMZA-930] samza-autoscaling YarnUtils json deserialisation fails with list values

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.10.1
• Fix Version/s: 0.10.1
• Assignee: Alex Buck
• Reporter: Alex Buck
• Created: 04/Apr/16 19:13
• Updated: 02/May/16 18:10
• Resolved: 02/May/16 18:10

Description

Current:

The getRunningAppId method in org.apache.samza.autoscaling.utils.YarnUtil attempts to deserialise the json from this endpoint /ws/v1/cluster/apps on the resource manager into the following shape: <Map<String, Map<String, List<Map<String, String>>>>>

The problem is that when there is a running job there is a property called resourceRequests which has a json array as a value. Therefore Jackson throws an exception when it tries to deserialise a json array into a string.

Proposed:

Deserialise the json into the following structure: <Map<String, Map<String, List<Map<String, Object>>>>>. The only property being queried for is the `state` so I think this is appropiate.

I have written the first test for this module. Very open to feedback and improvements.