"all" type search query spec (#3300)

* "all" type search query spec

* addressed comments

* added unit test

processing/src/main/java/io/druid/query/search/search/AllSearchQuerySpec.java

@@ -0,0 +1,57 @@
+/*
+ * Licensed to Metamarkets Group Inc. (Metamarkets) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. Metamarkets licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package io.druid.query.search.search;
+
+/**
+ */
+public class AllSearchQuerySpec implements SearchQuerySpec
+{
+  private static final byte CACHE_TYPE_ID = 0x7f;
+
+  @Override
+  public boolean accept(String dimVal)
+  {
+    return true;
+  }
+
+  @Override
+  public byte[] getCacheKey()
+  {
+    return new byte[]{CACHE_TYPE_ID};
+  }
+
+  @Override
+  public boolean equals(Object object)
+  {
+    return object instanceof AllSearchQuerySpec;
+  }
+
+  @Override
+  public int hashCode()
+  {
+    return CACHE_TYPE_ID;
+  }
+
+  @Override
+  public String toString()
+  {
+    return "AllSearchQuerySpec{}";
+  }
+}

processing/src/main/java/io/druid/query/search/search/SearchQuery.java

@@ -66,10 +66,9 @@ public class SearchQuery extends BaseQuery<Result<SearchResultValue>>
     this.granularity = granularity == null ? QueryGranularities.ALL : granularity;
     this.limit = (limit == 0) ? 1000 : limit;
     this.dimensions = dimensions;
-    this.querySpec = querySpec;
+    this.querySpec = querySpec == null ? new AllSearchQuerySpec() : querySpec;
 
     Preconditions.checkNotNull(querySegmentSpec, "Must specify an interval");
-    Preconditions.checkNotNull(querySpec, "Must specify a query");
   }
 
   @Override

processing/src/main/java/io/druid/query/search/search/SearchQuerySpec.java

@@ -29,7 +29,8 @@ import com.fasterxml.jackson.annotation.JsonTypeInfo;
     @JsonSubTypes.Type(name = "contains", value = ContainsSearchQuerySpec.class),
     @JsonSubTypes.Type(name = "insensitive_contains", value = InsensitiveContainsSearchQuerySpec.class),
     @JsonSubTypes.Type(name = "fragment", value = FragmentSearchQuerySpec.class),
-    @JsonSubTypes.Type(name = "regex", value = RegexSearchQuerySpec.class)
+    @JsonSubTypes.Type(name = "regex", value = RegexSearchQuerySpec.class),
+    @JsonSubTypes.Type(name = "all", value = AllSearchQuerySpec.class)
 })
 public interface SearchQuerySpec
 {

processing/src/test/java/io/druid/query/search/SearchQueryRunnerTest.java

@@ -550,6 +550,35 @@ public class SearchQueryRunnerTest
     );
   }
 
+  @Test
+  public void testSearchAll()
+  {
+    List<SearchHit> expectedHits = Lists.newLinkedList();
+    expectedHits.add(new SearchHit(QueryRunnerTestHelper.marketDimension, "spot", 837));
+    expectedHits.add(new SearchHit(QueryRunnerTestHelper.marketDimension, "total_market", 186));
+    expectedHits.add(new SearchHit(QueryRunnerTestHelper.marketDimension, "upfront", 186));
+
+    checkSearchQuery(
+        Druids.newSearchQueryBuilder()
+              .dataSource(QueryRunnerTestHelper.dataSource)
+              .granularity(QueryRunnerTestHelper.allGran)
+              .intervals(QueryRunnerTestHelper.fullOnInterval)
+              .dimensions(QueryRunnerTestHelper.marketDimension)
+              .query("")
+              .build(),
+        expectedHits
+    );
+    checkSearchQuery(
+        Druids.newSearchQueryBuilder()
+              .dataSource(QueryRunnerTestHelper.dataSource)
+              .granularity(QueryRunnerTestHelper.allGran)
+              .intervals(QueryRunnerTestHelper.fullOnInterval)
+              .dimensions(QueryRunnerTestHelper.marketDimension)
+              .build(),
+        expectedHits
+    );
+  }
+
   private void checkSearchQuery(Query searchQuery, List<SearchHit> expectedResults)
   {
     checkSearchQuery(searchQuery, runner, expectedResults);