Exception from geohash_grid aggregation with array of points (ES 1.4.0)

[mvdz]

Using a geohash_grid aggregation used to work on arrays of points, but with ES 1.4.0 an exception occurs instead. The following curl commands reproduce the issue on a clean installation of ES:

# create index with geo_point mapping
curl -XPUT localhost:9200/test -d '{
  "mappings": {
    "test": {
      "properties": {
        "points": {
          "type": "geo_point",
          "geohash_prefix": true
        }
      }
    }
  }
}'

# insert documents
curl -XPUT localhost:9200/test/test/1?refresh=true -d '{ "points": [[1,2], [2,3]] }'
curl -XPUT localhost:9200/test/test/2?refresh=true -d '{ "points": [[2,3], [3,4]] }'

# perform aggregation
curl -XGET localhost:9200/test/test/_search?pretty -d '{
  "size": 0,
  "aggs": {
    "a1": {
      "geohash_grid": {
        "field": "points",
        "precision": 3
      }
    }
  }
}'

On Elasticsearch 1.3.5 this produces the expected result:

...
  "aggregations" : {
    "a1" : {
      "buckets" : [ {
        "key" : "s09",
        "doc_count" : 2
      }, {
        "key" : "s0d",
        "doc_count" : 1
      }, {
        "key" : "s02",
        "doc_count" : 1
      } ]
    }
  }
...

However on Elasticsearch 1.4.0 this triggers a failure:

{
  "took" : 76,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 3,
    "failed" : 2,
    "failures" : [ {
      "index" : "test",
      "shard" : 2,
      "status" : 500,
      "reason" : "QueryPhaseExecutionException[[test][2]: query[ConstantScore(cache(_type:test))],from[0],size[0]: Query Failed [Failed to execute main query]]; nested: ArrayIndexOutOfBoundsException[1]; "
    }, {
      "index" : "test",
      "shard" : 3,
      "status" : 500,
      "reason" : "QueryPhaseExecutionException[[test][3]: query[ConstantScore(cache(_type:test))],from[0],size[0]: Query Failed [Failed to execute main query]]; nested: ArrayIndexOutOfBoundsException[1]; "
    } ]
  },
  "hits" : {
    "total" : 0,
    "max_score" : 0.0,
    "hits" : [ ]
  },
  "aggregations" : {
    "a1" : {
      "buckets" : [ ]
    }
  }
}

The log contains this exception:

[2014-11-17 17:28:25,121][DEBUG][action.search.type       ] [Franklin Storm] [test][3], node[-S9ijRKKQH-IEAr3sUW14Q], [P], s[STARTED]: Failed to execute [org.elasticsearch.action.search.SearchRequest@1fa40d49]
org.elasticsearch.search.query.QueryPhaseExecutionException: [test][3]: query[ConstantScore(cache(_type:test))],from[0],size[0]: Query Failed [Failed to execute main query]
    at org.elasticsearch.search.query.QueryPhase.execute(QueryPhase.java:163)
    at org.elasticsearch.search.SearchService.executeQueryPhase(SearchService.java:275)
    at org.elasticsearch.search.action.SearchServiceTransportAction$5.call(SearchServiceTransportAction.java:231)
    at org.elasticsearch.search.action.SearchServiceTransportAction$5.call(SearchServiceTransportAction.java:228)
    at org.elasticsearch.search.action.SearchServiceTransportAction$23.run(SearchServiceTransportAction.java:559)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:744)
Caused by: java.lang.ArrayIndexOutOfBoundsException: 1
    at org.elasticsearch.search.aggregations.bucket.geogrid.GeoHashGridParser$GeoGridFactory$CellValues.setDocument(GeoHashGridParser.java:154)
    at org.elasticsearch.search.aggregations.bucket.geogrid.GeoHashGridAggregator.collect(GeoHashGridAggregator.java:73)
    at org.elasticsearch.search.aggregations.AggregationPhase$AggregationsCollector.collect(AggregationPhase.java:161)
    at org.elasticsearch.common.lucene.MultiCollector.collect(MultiCollector.java:60)
    at org.apache.lucene.search.Weight$DefaultBulkScorer.scoreAll(Weight.java:193)
    at org.apache.lucene.search.Weight$DefaultBulkScorer.score(Weight.java:163)
    at org.apache.lucene.search.BulkScorer.score(BulkScorer.java:35)
    at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:621)
    at org.elasticsearch.search.internal.ContextIndexSearcher.search(ContextIndexSearcher.java:191)
    at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:309)
    at org.elasticsearch.search.query.QueryPhase.execute(QueryPhase.java:117)
    ... 7 more

[jpountz]

We did quite a significant refactoring of fielddata in 1.4 in order to better integrate with Lucene, I'm wondering that this could be related. I'm looking into it...