Update

Signed-off-by: Kai Huang <ahkcs@amazon.com>

Author: ahkcs

integ-test/src/yamlRestTest/resources/rest-api-spec/test/issues/4896.yml

@@ -7,6 +7,10 @@
 #
 # This can happen when an index has a disabled object field (enabled: false),
 # which allows storing documents without validating inner field names.
+#
+# Fix: The query engine now tolerates corrupt/invalid field names by returning null
+# for those fields (with a warning log), allowing the rest of the document to be
+# processed normally.
 
 setup:
   - do:
@@ -26,6 +30,8 @@ setup:
                 enabled: false
               "@timestamp":
                 type: date
+              message:
+                type: text
 
   # Index document with "." field name inside disabled object
   # OpenSearch allows this because the object is disabled (no validation of inner fields)
@@ -36,6 +42,7 @@ setup:
         refresh: true
         body:
           "@timestamp": "2025-11-26T17:10:00.000Z"
+          message: "test message"
           log:
             ".": "problematic value"
 
@@ -51,20 +58,30 @@ teardown:
         index: test_disabled_object_4896
 
 ---
-"Query index with dot-only field name in disabled object should return meaningful error":
+"Query index with dot-only field name in disabled object should succeed with valid fields":
   - skip:
       features:
         - headers
-        - regex
-  # Query should return meaningful error instead of ArrayIndexOutOfBoundsException
-  # The error is returned as 500 Internal Server Error with a meaningful message
   # Before the fix: ArrayIndexOutOfBoundsException: Index 0 out of bounds for length 0
-  # After the fix: Invalid field name '.': field names cannot consist only of dots
+  # After the fix: Query succeeds, invalid field returns null with a warning log,
+  # and valid fields (@timestamp, message) are returned normally
+  # Query valid fields - should succeed
+  - do:
+      headers:
+        Content-Type: 'application/json'
+      ppl:
+        body:
+          query: source=test_disabled_object_4896 | fields @timestamp, message
+  - match: { "total": 1 }
+  - match: { "datarows.0.0": "2025-11-26 17:10:00" }
+  - match: { "datarows.0.1": "test message" }
+
+  # Query all fields including log - should succeed without crash
+  # The log field with invalid "." field name will have null for that field
   - do:
-      catch: request
       headers:
         Content-Type: 'application/json'
       ppl:
         body:
           query: source=test_disabled_object_4896
-  - match: { "$body": "/Invalid field name.*cannot consist only of dots/" }
+  - match: { "total": 1 }

opensearch/src/main/java/org/opensearch/sql/opensearch/data/value/OpenSearchExprValueFactory.java

@@ -38,6 +38,8 @@
 import java.util.function.BiFunction;
 import lombok.Getter;
 import lombok.Setter;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.opensearch.OpenSearchParseException;
 import org.opensearch.common.time.DateFormatter;
 import org.opensearch.common.time.DateFormatters;
@@ -72,6 +74,8 @@
 
 /** Construct ExprValue from OpenSearch response. */
 public class OpenSearchExprValueFactory {
+  private static final Logger LOG = LogManager.getLogger(OpenSearchExprValueFactory.class);
+
   /** The Mapping of Field and ExprType. */
   private final Map<String, OpenSearchDataType> typeMapping;
 
@@ -373,15 +377,25 @@ private ExprValue parseStruct(Content content, String prefix, boolean supportArr
     content
         .map()
         .forEachRemaining(
-            entry ->
+            entry -> {
+              String fieldKey = entry.getKey();
+              String fullFieldPath = makeField(prefix, fieldKey);
+              try {
                 populateValueRecursive(
                     result,
-                    new JsonPath(entry.getKey()),
-                    parse(
-                        entry.getValue(),
-                        makeField(prefix, entry.getKey()),
-                        type(makeField(prefix, entry.getKey())),
-                        supportArrays)));
+                    new JsonPath(fieldKey),
+                    parse(entry.getValue(), fullFieldPath, type(fullFieldPath), supportArrays));
+              } catch (IllegalArgumentException e) {
+                // Return null for invalid field names (e.g., fields consisting only of dots)
+                // This can happen with disabled object fields that bypass field name validation
+                // Log warning to hint users about corrupt data
+                LOG.warn(
+                    "Field '{}' has invalid name and will return null: {}",
+                    fullFieldPath,
+                    e.getMessage());
+                result.tupleValue().put(fieldKey, ExprNullValue.of());
+              }
+            });
     return result;
   }
 

opensearch/src/test/java/org/opensearch/sql/opensearch/data/value/OpenSearchExprValueFactoryTest.java

@@ -1041,37 +1041,6 @@ public void testPopulateValueRecursive() {
     assertEquals(expectedValue, tupleValue);
   }
 
-  @Test
-  public void testJsonPathWithDotOnlyFieldName() {
-    IllegalArgumentException ex =
-        assertThrows(IllegalArgumentException.class, () -> new JsonPath("."));
-    assertTrue(ex.getMessage().contains("Invalid field name"));
-    assertTrue(ex.getMessage().contains("cannot consist only of dots"));
-  }
-
-  @Test
-  public void testJsonPathWithMultipleDotsFieldName() {
-    IllegalArgumentException ex =
-        assertThrows(IllegalArgumentException.class, () -> new JsonPath(".."));
-    assertTrue(ex.getMessage().contains("Invalid field name"));
-    assertTrue(ex.getMessage().contains("cannot consist only of dots"));
-  }
-
-  @Test
-  public void testJsonPathWithTripleDotsFieldName() {
-    IllegalArgumentException ex =
-        assertThrows(IllegalArgumentException.class, () -> new JsonPath("..."));
-    assertTrue(ex.getMessage().contains("Invalid field name"));
-  }
-
-  @Test
-  public void testJsonPathWithValidFieldName() {
-    // Regular field names should work
-    JsonPath path = new JsonPath("log.json.time");
-    assertEquals("log", path.getRootPath());
-    assertEquals(3, path.getPaths().size());
-  }
-
   public Map<String, ExprValue> tupleValue(String jsonString) {
     final ExprValue construct = exprValueFactory.construct(jsonString, false);
     return construct.tupleValue();