Get full RDD lineage for a spark job

[Ron Gonzalez]

Hi,  Can someone point me to a test case or share sample code that is able to 
extract the RDD graph from a Spark job anywhere during its lifecycle? I 
understand that Spark has UI that can show the graph of the execution so I'm 
hoping that is using some API somewhere that I could use.  I know RDD is the 
actual execution graph, so if there is also a more logical abstraction API 
closer to calls like map, filter, aggregate, etc., that would even be better.  
Appreciate any help...
Thanks,Ron