fail early if there is no input data for batch hadoop indexing

rtvt123 · Mar 7, 2015 · 6a0405d · 6a0405d
1 parent a54f93e
commit 6a0405d
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/indexing-hadoop/src/main/java/io/druid/indexer/IndexGeneratorJob.java b/indexing-hadoop/src/main/java/io/druid/indexer/IndexGeneratorJob.java
@@ -169,7 +169,11 @@ public boolean run()
 
       SortableBytes.useSortableBytesAsMapOutputKey(job);
 
-      job.setNumReduceTasks(Iterables.size(config.getAllBuckets().get()));
+      int numReducers = Iterables.size(config.getAllBuckets().get());
+      if(numReducers == 0) {
+        throw new RuntimeException("No buckets?? seems there is no data to index.");
+      }
+      job.setNumReduceTasks(numReducers);
       job.setPartitionerClass(IndexGeneratorPartitioner.class);
 
       setReducerClass(job);