Traps may not cross Map and Reduce boundaries

[Renaud Delbru]

Hi,

I am trying to setup a trap on a simple worddcount assembly, but I got
the following error during the planner execution:

Exception in thread "main" cascading.flow.PlannerException: traps may
not cross Map and Reduce boundaries: word-count

My code looks like:
final Tap hBaseTap = ...;
final Tap sink = ...;
final Tap trap = new Hfs(new TextLine(), output + "-trap",
SinkMode.REPLACE);

final Pipe count = new WordCount("word-count", new Fields("content"),
new Fields("term", "count"));
final Flow flow = flowConnector.connect("analytics", hBaseTap, sink,
trap, count);

By looking at the unit tests for this FlowConnector#connect methods,
it seems there is no difference (apart that I am using an assembly
wrapping the each, groupby, every operations).

Could someone can explain me what is wrong here ?
Thanks
--
Renaud Delbru

[Chris K Wensel]

Try using wip-1.1. This restriction goes away.

http://www.concurrentinc.com/downloads/

cheers,
chris

--
Chris K Wensel
ch...@concurrentinc.com
http://www.concurrentinc.com

[Renaud Delbru]

Hi Chris,

Ok, but is there a hbase tap available for wip 1.1. ?
Is there a bug changes in the API (i.e. is my application written with
cascading 1.06 will still be compatible with wip 1.1 or do I have to
rewrite some part ?)

Thanks
--
Renaud Delbru

[Renaud Delbru]

I meant, is there an interface change in the API (not a bug change).

thanks
--
Renaud Delbru

[Chris K Wensel]

wip-1.1 is a drop in replacement to 1.0.x. you don't need to change
your code.

ckw

[Renaud Delbru]

Hi Chris,

I updated to 1.1.0-59. It works perfectly, and no change in my code
has been necessary. The HbaseTap works also great.

Thanks.
--
Renaud Delbru

[Chris K Wensel]

great news!

cheers,
chris