Add a test for key queries

Author: dmdashenkov

datastore/src/test/java/io/spine/server/storage/datastore/TransactionWrapperTest.java

@@ -26,6 +26,7 @@
 import com.google.cloud.datastore.KeyFactory;
 import com.google.cloud.datastore.PathElement;
 import com.google.cloud.datastore.Query;
+import com.google.cloud.datastore.StructuredQuery;
 import com.google.common.collect.ImmutableList;
 import com.google.protobuf.Empty;
 import io.spine.testing.SlowTest;
@@ -367,4 +368,23 @@ void lookupBulk() {
                     .containsExactlyElementsIn(entities);
         }
     }
+
+    @Test
+    @DisplayName("NOT execute a key query")
+    void keyQuery() {
+        int count = 2;
+        List<Entity> entities = generate(() -> keyFactory.newKey(newUuid()))
+                .limit(count)
+                .map(key -> Entity.newBuilder(key).build())
+                .collect(toList());
+        datastore.createOrUpdate(entities);
+        try (TransactionWrapper tx = datastore.newTransaction()) {
+            StructuredQuery<Key> query = Query
+                    .newKeyQueryBuilder()
+                    .setKind(TEST_KIND.value())
+                    .build();
+            assertThrows(DatastoreException.class, () -> tx.read(query));
+            tx.commit();
+        }
+    }
 }

license-report.md

@@ -650,7 +650,7 @@
  The dependencies distributed under several licenses, are used according their commercial-use-friendly license.
 
 
-This report was generated on **Tue Jan 28 17:05:29 EET 2020** using [Gradle-License-Report plugin](https://github.com/jk1/Gradle-License-Report) by Evgeny Naumenko, licensed under [Apache 2.0 License](https://github.com/jk1/Gradle-License-Report/blob/master/LICENSE).
+This report was generated on **Tue Jan 28 17:24:57 EET 2020** using [Gradle-License-Report plugin](https://github.com/jk1/Gradle-License-Report) by Evgeny Naumenko, licensed under [Apache 2.0 License](https://github.com/jk1/Gradle-License-Report/blob/master/LICENSE).
 
 
 
@@ -1309,7 +1309,7 @@ This report was generated on **Tue Jan 28 17:05:29 EET 2020** using [Gradle-Lice
  The dependencies distributed under several licenses, are used according their commercial-use-friendly license.
 
 
-This report was generated on **Tue Jan 28 17:05:31 EET 2020** using [Gradle-License-Report plugin](https://github.com/jk1/Gradle-License-Report) by Evgeny Naumenko, licensed under [Apache 2.0 License](https://github.com/jk1/Gradle-License-Report/blob/master/LICENSE).
+This report was generated on **Tue Jan 28 17:24:59 EET 2020** using [Gradle-License-Report plugin](https://github.com/jk1/Gradle-License-Report) by Evgeny Naumenko, licensed under [Apache 2.0 License](https://github.com/jk1/Gradle-License-Report/blob/master/LICENSE).
 
 
 
@@ -1985,4 +1985,4 @@ This report was generated on **Tue Jan 28 17:05:31 EET 2020** using [Gradle-Lice
  The dependencies distributed under several licenses, are used according their commercial-use-friendly license.
 
 
-This report was generated on **Tue Jan 28 17:05:32 EET 2020** using [Gradle-License-Report plugin](https://github.com/jk1/Gradle-License-Report) by Evgeny Naumenko, licensed under [Apache 2.0 License](https://github.com/jk1/Gradle-License-Report/blob/master/LICENSE).
+This report was generated on **Tue Jan 28 17:25:01 EET 2020** using [Gradle-License-Report plugin](https://github.com/jk1/Gradle-License-Report) by Evgeny Naumenko, licensed under [Apache 2.0 License](https://github.com/jk1/Gradle-License-Report/blob/master/LICENSE).