Merge pull request #474 from metamx/groupby-dimextractionfn

support dimension extraction functions in group by

processing/src/main/java/io/druid/query/groupby/GroupByQueryEngine.java

@@ -44,6 +44,7 @@ import io.druid.query.aggregation.AggregatorFactory;
 import io.druid.query.aggregation.BufferAggregator;
 import io.druid.query.aggregation.PostAggregator;
 import io.druid.query.dimension.DimensionSpec;
+import io.druid.query.extraction.DimExtractionFn;
 import io.druid.segment.Cursor;
 import io.druid.segment.DimensionSelector;
 import io.druid.segment.StorageAdapter;
@@ -398,9 +399,14 @@ public class GroupByQueryEngine
                   ByteBuffer keyBuffer = input.getKey().duplicate();
                   for (int i = 0; i < dimensions.size(); ++i) {
                     final DimensionSelector dimSelector = dimensions.get(i);
+                    final DimExtractionFn fn = dimensionSpecs.get(i).getDimExtractionFn();
                     final int dimVal = keyBuffer.getInt();
                     if (dimSelector.getValueCardinality() != dimVal) {
-                      theEvent.put(dimNames.get(i), dimSelector.lookupName(dimVal));
+                      if(fn != null) {
+                        theEvent.put(dimNames.get(i), fn.apply(dimSelector.lookupName(dimVal)));
+                      } else {
+                        theEvent.put(dimNames.get(i), dimSelector.lookupName(dimVal));
+                      }
                     }
                   }
 

processing/src/test/java/io/druid/query/groupby/GroupByQueryRunnerTest.java

@@ -45,6 +45,9 @@ import io.druid.query.aggregation.LongSumAggregatorFactory;
 import io.druid.query.aggregation.MaxAggregatorFactory;
 import io.druid.query.dimension.DefaultDimensionSpec;
 import io.druid.query.dimension.DimensionSpec;
+import io.druid.query.dimension.ExtractionDimensionSpec;
+import io.druid.query.extraction.PartialDimExtractionFn;
+import io.druid.query.extraction.RegexDimExtractionFn;
 import io.druid.query.filter.JavaScriptDimFilter;
 import io.druid.query.filter.RegexDimFilter;
 import io.druid.query.groupby.having.EqualToHavingSpec;
@@ -178,6 +181,47 @@ public class GroupByQueryRunnerTest
     TestHelper.assertExpectedObjects(expectedResults, results, "");
   }
 
+  @Test
+  public void testGroupByWithDimExtractionFn()
+  {
+    GroupByQuery query = GroupByQuery
+        .builder()
+        .setDataSource(QueryRunnerTestHelper.dataSource)
+        .setQuerySegmentSpec(QueryRunnerTestHelper.firstToThird)
+        .setDimensions(Lists.<DimensionSpec>newArrayList(new ExtractionDimensionSpec("quality", "alias", new RegexDimExtractionFn("(\\w{1})"))))
+        .setAggregatorSpecs(
+            Arrays.<AggregatorFactory>asList(
+                QueryRunnerTestHelper.rowsCount,
+                new LongSumAggregatorFactory("idx", "index")
+            )
+        )
+        .setGranularity(QueryRunnerTestHelper.dayGran)
+        .build();
+
+    List<Row> expectedResults = Arrays.asList(
+        createExpectedRow("2011-04-01", "alias", "a", "rows", 1L, "idx", 135L),
+        createExpectedRow("2011-04-01", "alias", "b", "rows", 1L, "idx", 118L),
+        createExpectedRow("2011-04-01", "alias", "e", "rows", 1L, "idx", 158L),
+        createExpectedRow("2011-04-01", "alias", "h", "rows", 1L, "idx", 120L),
+        createExpectedRow("2011-04-01", "alias", "m", "rows", 3L, "idx", 2870L),
+        createExpectedRow("2011-04-01", "alias", "n", "rows", 1L, "idx", 121L),
+        createExpectedRow("2011-04-01", "alias", "p", "rows", 3L, "idx", 2900L),
+        createExpectedRow("2011-04-01", "alias", "t", "rows", 2L, "idx", 197L),
+
+        createExpectedRow("2011-04-02", "alias", "a", "rows", 1L, "idx", 147L),
+        createExpectedRow("2011-04-02", "alias", "b", "rows", 1L, "idx", 112L),
+        createExpectedRow("2011-04-02", "alias", "e", "rows", 1L, "idx", 166L),
+        createExpectedRow("2011-04-02", "alias", "h", "rows", 1L, "idx", 113L),
+        createExpectedRow("2011-04-02", "alias", "m", "rows", 3L, "idx", 2447L),
+        createExpectedRow("2011-04-02", "alias", "n", "rows", 1L, "idx", 114L),
+        createExpectedRow("2011-04-02", "alias", "p", "rows", 3L, "idx", 2505L),
+        createExpectedRow("2011-04-02", "alias", "t", "rows", 2L, "idx", 223L)
+    );
+
+    Iterable<Row> results = runQuery(query);
+    TestHelper.assertExpectedObjects(expectedResults, results, "");
+  }
+
   @Test
   public void testGroupByWithTimeZone()
   {