ShardingInfoTest: unittest for shardId calculations

Author: fruch

driver-core/src/test/java/com/datastax/driver/core/ShardingInfoTest.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright ScyllaDB, Inc.
+ *
+ * Licensed 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 com.datastax.driver.core;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.nio.ByteBuffer;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import org.testng.annotations.Test;
+
+public class ShardingInfoTest {
+
+  @Test(groups = "unit")
+  public void shardIdCalculationTest() {
+    // Verify that our Murmur hash calculates the correct shard for specific keys.
+    Token.Factory factory = Token.M3PToken.FACTORY;
+
+    Map<String, List<String>> params =
+        new HashMap<String, List<String>>() {
+          {
+            put("SCYLLA_SHARD", Collections.singletonList("1"));
+            put("SCYLLA_NR_SHARDS", Collections.singletonList("12"));
+            put(
+                "SCYLLA_PARTITIONER",
+                Collections.singletonList("org.apache.cassandra.dht.Murmur3Partitioner"));
+            put("SCYLLA_SHARDING_ALGORITHM", Collections.singletonList("biased-token-round-robin"));
+            put("SCYLLA_SHARDING_IGNORE_MSB", Collections.singletonList("12"));
+          }
+        };
+    ShardingInfo.ConnectionShardingInfo sharding = ShardingInfo.parseShardingInfo(params);
+    assertThat(sharding).isNotNull();
+    assertThat(sharding.shardId).isEqualTo(1);
+
+    Token token1 =
+        factory.hash(
+            ByteBuffer.wrap(
+                new byte[] {
+                  'a',
+                }));
+    assertThat(sharding.shardingInfo.shardId(token1)).isEqualTo(4);
+
+    Token token2 =
+        factory.hash(
+            ByteBuffer.wrap(
+                new byte[] {
+                  'b',
+                }));
+    assertThat(sharding.shardingInfo.shardId(token2)).isEqualTo(6);
+
+    Token token3 =
+        factory.hash(
+            ByteBuffer.wrap(
+                new byte[] {
+                  'c',
+                }));
+    assertThat(sharding.shardingInfo.shardId(token3)).isEqualTo(6);
+
+    Token token4 =
+        factory.hash(
+            ByteBuffer.wrap(
+                new byte[] {
+                  'e',
+                }));
+    assertThat(sharding.shardingInfo.shardId(token4)).isEqualTo(4);
+
+    Token token5 =
+        factory.hash(
+            ByteBuffer.wrap(
+                new byte[] {
+                  '1', '0', '0', '0', '0', '0',
+                }));
+    assertThat(sharding.shardingInfo.shardId(token5)).isEqualTo(2);
+  }
+}