[core] Add ignoreUnknown to Snapshot (#3202)

paimon-core/src/main/java/org/apache/paimon/Snapshot.java

@@ -29,6 +29,7 @@
 
 import org.apache.paimon.shade.jackson2.com.fasterxml.jackson.annotation.JsonCreator;
 import org.apache.paimon.shade.jackson2.com.fasterxml.jackson.annotation.JsonGetter;
+import org.apache.paimon.shade.jackson2.com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import org.apache.paimon.shade.jackson2.com.fasterxml.jackson.annotation.JsonInclude;
 import org.apache.paimon.shade.jackson2.com.fasterxml.jackson.annotation.JsonProperty;
 
@@ -64,6 +65,7 @@
  *       there is no compatibility issue.
  * </ul>
  */
+@JsonIgnoreProperties(ignoreUnknown = true)
 public class Snapshot {
 
     public static final long FIRST_SNAPSHOT_ID = 1;
@@ -142,6 +144,8 @@ public class Snapshot {
     private final long timeMillis;
 
     @JsonProperty(FIELD_LOG_OFFSETS)
+    @JsonInclude(JsonInclude.Include.NON_NULL)
+    @Nullable
     private final Map<Integer, Long> logOffsets;
 
     // record count of all changes occurred in this snapshot
@@ -159,6 +163,7 @@ public class Snapshot {
     // record count of all changelog produced in this snapshot
     // null for paimon <= 0.3
     @JsonProperty(FIELD_CHANGELOG_RECORD_COUNT)
+    @JsonInclude(JsonInclude.Include.NON_NULL)
     @Nullable
     private final Long changelogRecordCount;
 
@@ -167,6 +172,7 @@ public class Snapshot {
     // null if there is no watermark in new committing, and the previous snapshot does not have a
     // watermark
     @JsonProperty(FIELD_WATERMARK)
+    @JsonInclude(JsonInclude.Include.NON_NULL)
     @Nullable
     private final Long watermark;
 

paimon-core/src/test/java/org/apache/paimon/SnapshotTest.java

@@ -0,0 +1,44 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 org.apache.paimon;
+
+import org.junit.jupiter.api.Test;
+
+class SnapshotTest {
+
+    @Test
+    public void testJsonIgnoreProperties() {
+        Snapshot.fromJson(
+                "{\n"
+                        + "  \"version\" : 3,\n"
+                        + "  \"id\" : 5,\n"
+                        + "  \"schemaId\" : 0,\n"
+                        + "  \"baseManifestList\" : null,\n"
+                        + "  \"deltaManifestList\" : null,\n"
+                        + "  \"changelogManifestList\" : null,\n"
+                        + "  \"commitUser\" : null,\n"
+                        + "  \"commitIdentifier\" : 0,\n"
+                        + "  \"commitKind\" : \"APPEND\",\n"
+                        + "  \"timeMillis\" : 1234,\n"
+                        + "  \"totalRecordCount\" : null,\n"
+                        + "  \"deltaRecordCount\" : null,\n"
+                        + "  \"unknownKey\" : 22222\n"
+                        + "}");
+    }
+}