SOLR-12083: Fix RealTime GET to work on a cluster running CDCR when using Solr's in-place updates

solr/CHANGES.txt

@@ -318,6 +318,9 @@ Bug Fixes
 * SOLR-12064: JSON Facet API: fix bug where a limit of -1 in conjunction with multiple facets or
   missing=true caused an NPE or AIOOBE. (Karthik Ramachandran via yonik)
 
+* SOLR-12083: Fix RealTime GET to work on a cluster running CDCR when using Solr's in-place updates
+  (Amrit Sarkar, Varun Thacker)
+
 
 Optimizations
 ----------------------

solr/core/src/java/org/apache/solr/handler/component/RealTimeGetComponent.java

@@ -80,6 +80,7 @@ import org.apache.solr.search.SolrDocumentFetcher;
 import org.apache.solr.search.SolrIndexSearcher;
 import org.apache.solr.search.SolrReturnFields;
 import org.apache.solr.search.SyntaxError;
+import org.apache.solr.update.CdcrUpdateLog;
 import org.apache.solr.update.DocumentBuilder;
 import org.apache.solr.update.IndexFingerprint;
 import org.apache.solr.update.PeerSync;
@@ -255,7 +256,11 @@ public class RealTimeGetComponent extends SearchComponent
                if (oper == UpdateLog.ADD) {
                  doc = toSolrDoc((SolrInputDocument)entry.get(entry.size()-1), core.getLatestSchema());
                } else if (oper == UpdateLog.UPDATE_INPLACE) {
-                 assert entry.size() == 5;
+                 if (ulog instanceof CdcrUpdateLog) {
+                   assert entry.size() == 6;
+                 } else {
+                   assert entry.size() == 5;
+                 }
                  // For in-place update case, we have obtained the partial document till now. We need to
                  // resolve it to a full document to be returned to the user.
                  doc = resolveFullDocument(core, idBytes.get(), rsp.getReturnFields(), (SolrInputDocument)entry.get(entry.size()-1), entry, null);
@@ -395,7 +400,7 @@ public class RealTimeGetComponent extends SearchComponent
    */
   private static SolrDocument resolveFullDocument(SolrCore core, BytesRef idBytes,
                                            ReturnFields returnFields, SolrInputDocument partialDoc, List logEntry, Set<String> onlyTheseFields) throws IOException {
-    if (idBytes == null || logEntry.size() != 5) {
+    if (idBytes == null || (logEntry.size() != 5 && logEntry.size() != 6)) {
       throw new SolrException(ErrorCode.INVALID_STATE, "Either Id field not present in partial document or log entry doesn't have previous version.");
     }
     long prevPointer = (long) logEntry.get(UpdateLog.PREV_POINTER_IDX);
@@ -541,7 +546,11 @@ public class RealTimeGetComponent extends SearchComponent
         }
         switch (oper) {
           case UpdateLog.UPDATE_INPLACE:
-            assert entry.size() == 5;
+            if (ulog instanceof CdcrUpdateLog) {
+              assert entry.size() == 6;
+            } else {
+              assert entry.size() == 5;
+            }
 
             if (resolveFullDocument) {
               SolrInputDocument doc = (SolrInputDocument)entry.get(entry.size()-1);

solr/core/src/test-files/solr/collection1/conf/solrconfig-tlog.xml

@@ -54,7 +54,7 @@
   </peerSync>
 
   <updateHandler class="solr.DirectUpdateHandler2">
-    <updateLog>
+    <updateLog class="${solr.tests.ulog:solr.UpdateLog}">
       <str name="dir">${solr.ulog.dir:}</str>
       <str name="maxNumLogsToKeep">${solr.ulog.maxNumLogsToKeep:10}</str>
       <str name="numRecordsToKeep">${solr.ulog.numRecordsToKeep:100}</str>

solr/core/src/test/org/apache/solr/search/TestRealTimeGet.java

@@ -42,6 +42,7 @@ public class TestRealTimeGet extends TestRTGBase {
 
   @BeforeClass
   public static void beforeClass() throws Exception {
+    randomizeUpdateLogImpl();
     initCore("solrconfig-tlog.xml","schema_latest.xml");
   }
 

solr/core/src/test/org/apache/solr/update/TestInPlaceUpdatesDistrib.java

@@ -81,6 +81,8 @@ public class TestInPlaceUpdatesDistrib extends AbstractFullDistribZkTestBase {
     // asserting inplace updates happen by checking the internal [docid]
     systemSetPropertySolrTestsMergePolicyFactory(NoMergePolicyFactory.class.getName());
 
+    randomizeUpdateLogImpl();
+
     initCore(configString, schemaString);
     
     // sanity check that autocommits are disabled

solr/test-framework/src/java/org/apache/solr/SolrTestCaseJ4.java

@@ -802,6 +802,11 @@ public abstract class SolrTestCaseJ4 extends LuceneTestCase {
       System.clearProperty("solr.directoryFactory");
     }
 
+    if (System.getProperty(UPDATELOG_SYSPROP) != null) {
+      // clears the updatelog sysprop at the end of the test run
+      System.clearProperty(UPDATELOG_SYSPROP);
+    }
+    
     solrConfig = null;
     h = null;
     lrf = null;
@@ -2704,6 +2709,20 @@ public abstract class SolrTestCaseJ4 extends LuceneTestCase {
    */
   public static final String NUMERIC_DOCVALUES_SYSPROP = "solr.tests.numeric.dv";
 
+  public static final String UPDATELOG_SYSPROP = "solr.tests.ulog";
+
+  /**
+   * randomizes the updateLog between different update log implementations for better test coverage
+   */
+  public static void randomizeUpdateLogImpl() {
+    if (random().nextBoolean()) {
+      System.setProperty(UPDATELOG_SYSPROP, "solr.CdcrUpdateLog");
+    } else {
+      System.setProperty(UPDATELOG_SYSPROP,"solr.UpdateLog");
+    }
+    log.info("updateLog impl={}", System.getProperty(UPDATELOG_SYSPROP));
+  }
+
   /**
    * Sets various sys props related to user specified or randomized choices regarding the types 
    * of numerics that should be used in tests.