From deeefa89eb3e645fd82ce36deaeba62fd0b276b5 Mon Sep 17 00:00:00 2001
From: Sunjeet Singh <sunjeets@netflix.com>
Date: Sun, 8 Oct 2023 19:00:14 -0700
Subject: [PATCH] Add tests for resharding with type filter

---
 .../HollowObjectTypeDataElementsJoiner.java   |  5 +--
 ...owObjectTypeDataElementsSplitJoinTest.java | 23 ++++++++++--
 ...owObjectTypeDataElementsSplitJoinTest.java | 22 ++++++++++++
 .../object/HollowObjectTypeReadStateTest.java | 35 +++++++++++++++++++
 4 files changed, 81 insertions(+), 4 deletions(-)

diff --git a/hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsJoiner.java b/hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsJoiner.java
index b91b317759..806c11ce53 100644
--- a/hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsJoiner.java
+++ b/hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsJoiner.java
@@ -88,7 +88,8 @@ void populateStats(HollowObjectTypeDataElements to, HollowObjectTypeDataElements
             to.bitsPerRecord += to.bitsPerField[fieldIdx];
         }
 
-        to.bitsPerUnfilteredField = from[0].bitsPerUnfilteredField;
-        to.unfilteredFieldIsIncluded = from[0].unfilteredFieldIsIncluded;
+        // unused
+        //  to.bitsPerUnfilteredField
+        //  to.unfilteredFieldIsIncluded
     }
 }
diff --git a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/AbstractHollowObjectTypeDataElementsSplitJoinTest.java b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/AbstractHollowObjectTypeDataElementsSplitJoinTest.java
index d149acffab..adffb055f8 100644
--- a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/AbstractHollowObjectTypeDataElementsSplitJoinTest.java
+++ b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/AbstractHollowObjectTypeDataElementsSplitJoinTest.java
@@ -5,7 +5,10 @@
 
 import com.netflix.hollow.api.objects.generic.GenericHollowObject;
 import com.netflix.hollow.core.AbstractStateEngineTest;
+import com.netflix.hollow.core.read.engine.HollowReadStateEngine;
+import com.netflix.hollow.core.read.filter.HollowFilterConfig;
 import com.netflix.hollow.core.schema.HollowObjectSchema;
+import com.netflix.hollow.core.util.StateEngineRoundTripper;
 import com.netflix.hollow.core.write.HollowObjectTypeWriteState;
 import com.netflix.hollow.core.write.HollowObjectWriteRecord;
 import java.io.IOException;
@@ -39,7 +42,7 @@ protected void initializeTypeStates() {
         writeStateEngine.addTypeState(new HollowObjectTypeWriteState(schema));
     }
 
-    protected HollowObjectTypeReadState populateTypeStateWith(int numRecords) throws IOException {
+    private void populateWriteStateEngine(int numRecords) {
         initWriteStateEngine();
         HollowObjectWriteRecord rec = new HollowObjectWriteRecord(schema);
         for(int i=0;i<numRecords;i++) {
@@ -51,17 +54,33 @@ protected HollowObjectTypeReadState populateTypeStateWith(int numRecords) throws
 
             writeStateEngine.add("TestObject", rec);
         }
+    }
+
+    protected HollowObjectTypeReadState populateTypeStateWith(int numRecords) throws IOException {
+        populateWriteStateEngine(numRecords);
         roundTripSnapshot();
         return (HollowObjectTypeReadState) readStateEngine.getTypeState("TestObject");
     }
 
+    protected HollowObjectTypeReadState populateTypeStateWithFilter(int numRecords) throws IOException {
+        populateWriteStateEngine(numRecords);
+        readStateEngine = new HollowReadStateEngine();
+        HollowFilterConfig readFilter = new HollowFilterConfig(true);
+        readFilter.addField("TestObject", "intField");
+        StateEngineRoundTripper.roundTripSnapshot(writeStateEngine, readStateEngine, readFilter);
+        return (HollowObjectTypeReadState) readStateEngine.getTypeState("TestObject");
+    }
+
     protected void assertDataUnchanged(int numRecords) {
         for(int i=0;i<numRecords;i++) {
             GenericHollowObject obj = new GenericHollowObject(readStateEngine, "TestObject", i);
             assertEquals(i, obj.getLong("longField"));
             assertEquals("Value"+i, obj.getString("stringField"));
-            assertEquals(i, obj.getInt("intField"));
+            HollowObjectTypeReadState typeState = (HollowObjectTypeReadState) readStateEngine.getTypeState("TestObject");
             assertEquals((double)i, obj.getDouble("doubleField"), 0);
+            if (typeState.getSchema().numFields() == 4) {   // filtered
+                assertEquals(i, obj.getInt("intField"));
+            }
         }
     }
 }
diff --git a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsSplitJoinTest.java b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsSplitJoinTest.java
index a5efef1fdb..d87b389ab6 100644
--- a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsSplitJoinTest.java
+++ b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsSplitJoinTest.java
@@ -44,6 +44,28 @@ public void testSplitThenJoin() throws IOException {
         }
     }
 
+    @Test
+    public void testSplitThenJoinWithFilter() throws IOException {
+        HollowObjectTypeDataElementsSplitter splitter = new HollowObjectTypeDataElementsSplitter();
+        HollowObjectTypeDataElementsJoiner joiner = new HollowObjectTypeDataElementsJoiner();
+
+        int numSplits = 2;
+        for (int numRecords=0;numRecords<1*1000;numRecords++) {
+            HollowObjectTypeReadState typeReadState = populateTypeStateWithFilter(numRecords);
+            assertEquals(1, typeReadState.numShards());
+            assertDataUnchanged(numRecords);
+            HollowChecksum origChecksum = typeReadState.getChecksum(typeReadState.getSchema());
+
+            HollowObjectTypeDataElements[] splitElements = splitter.split(typeReadState.currentDataElements()[0], numSplits);
+            HollowObjectTypeDataElements joinedElements = joiner.join(splitElements);
+            typeReadState.setCurrentData(joinedElements);
+
+            assertDataUnchanged(numRecords);
+            HollowChecksum resultChecksum = typeReadState.getChecksum(typeReadState.getSchema());
+            assertEquals(origChecksum, resultChecksum);
+        }
+    }
+
     // manually invoked
     // @Test
     public void testSplittingAndJoiningWithSnapshotBlob() throws Exception {
diff --git a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeReadStateTest.java b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeReadStateTest.java
index be37bf3037..fbbfd7cfe6 100644
--- a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeReadStateTest.java
+++ b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeReadStateTest.java
@@ -82,6 +82,41 @@ public void testResharding() throws Exception {
         }
     }
 
+    @Test
+    public void testReshardingWithFilter() throws Exception {
+
+        for (int shardingFactor : new int[]{2, 64})
+        {
+            for(int numRecords=1;numRecords<=100000;numRecords+=new Random().nextInt(10000))
+            {
+                HollowObjectTypeReadState objectTypeReadState = populateTypeStateWithFilter(numRecords);
+                assertDataUnchanged(numRecords);
+
+                // Splitting shards
+                {
+                    int prevShardCount = objectTypeReadState.numShards();
+                    int newShardCount = shardingFactor * prevShardCount;
+                    objectTypeReadState.reshard(newShardCount);
+
+                    assertEquals(newShardCount, objectTypeReadState.numShards());
+                    assertEquals(newShardCount, shardingFactor * prevShardCount);
+                }
+                assertDataUnchanged(numRecords);
+
+                // Joining shards
+                {
+                    int prevShardCount = objectTypeReadState.numShards();
+                    int newShardCount = prevShardCount / shardingFactor;
+                    objectTypeReadState.reshard(newShardCount);
+
+                    assertEquals(newShardCount, objectTypeReadState.numShards());
+                    assertEquals(shardingFactor * newShardCount, prevShardCount);
+                }
+                assertDataUnchanged(numRecords);
+            }
+        }
+    }
+
     @Test
     public void testReshardingIntermediateStages_expandWithOriginalDataElements() throws Exception {
         for (int shardingFactor : new int[]{2, 4, 8}) {