Fix bug in low cardinality ordinal terms aggs

rest-api-spec/src/main/resources/rest-api-spec/test/search.aggregation/370_doc_count_field.yml

@@ -18,15 +18,15 @@ setup:
         refresh: true
         body:
           - '{"index": {}}'
-          - '{"_doc_count": 10, "str": "abc", "number" : 500 }'
+          - '{"_doc_count": 10, "str": "abc", "number" : 500, "unmapped": "abc" }'
           - '{"index": {}}'
-          - '{"_doc_count": 5, "str": "xyz", "number" : 100 }'
+          - '{"_doc_count": 5, "str": "xyz", "number" : 100, "unmapped": "xyz" }'
           - '{"index": {}}'
-          - '{"_doc_count": 7, "str": "foo", "number" : 100 }'
+          - '{"_doc_count": 7, "str": "foo", "number" : 100, "unmapped": "foo" }'
           - '{"index": {}}'
-          - '{"_doc_count": 1, "str": "foo", "number" : 200 }'
+          - '{"_doc_count": 1, "str": "foo", "number" : 200, "unmapped": "foo" }'
           - '{"index": {}}'
-          - '{"str": "abc", "number" : 500 }'
+          - '{"str": "abc", "number" : 500, "unmapped": "abc" }'
 
 ---
 "Test numeric terms agg with doc_count":
@@ -50,7 +50,7 @@ setup:
 
 
 ---
-"Test string terms agg with doc_count":
+"Test keyword terms agg with doc_count":
   - skip:
       version: " - 7.99.99"
       reason: "Doc count fields are only implemented in 8.0"
@@ -67,3 +67,29 @@ setup:
   - match: { aggregations.str_terms.buckets.1.doc_count: 8 }
   - match: { aggregations.str_terms.buckets.2.key: "xyz" }
   - match: { aggregations.str_terms.buckets.2.doc_count: 5 }
+
+---
+
+"Test unmapped string terms agg with doc_count":
+  - skip:
+      version: " - 7.99.99"
+      reason: "Doc count fields are only implemented in 8.0"
+  - do:
+      bulk:
+        index: test_2
+        refresh: true
+        body:
+          - '{"index": {}}'
+          - '{"_doc_count": 10, "str": "abc" }'
+          - '{"index": {}}'
+          - '{"str": "abc" }'
+  - do:
+      search:
+        index: test_2
+        rest_total_hits_as_int: true
+        body: { "size" : 0, "aggs" : { "str_terms" : { "terms" : { "field" : "str.keyword" } } } }
+
+  - match: { hits.total: 2 }
+  - length: { aggregations.str_terms.buckets: 1 }
+  - match: { aggregations.str_terms.buckets.0.key: "abc" }
+  - match: { aggregations.str_terms.buckets.0.doc_count: 11 }

server/src/main/java/org/elasticsearch/search/aggregations/bucket/BucketsAggregator.java

@@ -54,7 +54,7 @@ public abstract class BucketsAggregator extends AggregatorBase {
     private final BigArrays bigArrays;
     private final IntConsumer multiBucketConsumer;
     private IntArray docCounts;
-    private DocCountProvider docCountProvider;
+    protected final DocCountProvider docCountProvider;
 
     public BucketsAggregator(String name, AggregatorFactories factories, SearchContext context, Aggregator parent,
             CardinalityUpperBound bucketCardinality, Map<String, Object> metadata) throws IOException {

server/src/main/java/org/elasticsearch/search/aggregations/bucket/terms/GlobalOrdinalsStringTermsAggregator.java

@@ -305,6 +305,7 @@ public LeafBucketCollector getLeafCollector(LeafReaderContext ctx, LeafBucketCol
             assert sub == LeafBucketCollector.NO_OP_COLLECTOR;
             final SortedDocValues singleValues = DocValues.unwrapSingleton(segmentOrds);
             mapping = valuesSource.globalOrdinalsMapping(ctx);
+            docCountProvider.setLeafReaderContext(ctx);
             // Dense mode doesn't support include/exclude so we don't have to check it here.
             if (singleValues != null) {
                 segmentsWithSingleValuedOrds++;
@@ -316,7 +317,8 @@ public void collect(int doc, long owningBucketOrd) throws IOException {
                             return;
                         }
                         int ord = singleValues.ordValue();
-                        segmentDocCounts.increment(ord + 1, 1);
+                        int docCount = docCountProvider.getDocCount(doc);
+                        segmentDocCounts.increment(ord + 1, docCount);
                     }
                 });
             }
@@ -329,7 +331,8 @@ public void collect(int doc, long owningBucketOrd) throws IOException {
                         return;
                     }
                     for (long segmentOrd = segmentOrds.nextOrd(); segmentOrd != NO_MORE_ORDS; segmentOrd = segmentOrds.nextOrd()) {
-                        segmentDocCounts.increment(segmentOrd + 1, 1);
+                        int docCount = docCountProvider.getDocCount(doc);
+                        segmentDocCounts.increment(segmentOrd + 1, docCount);
                     }
                 }
             });