Make new TimeBucket in ElasticSearch compatible with old versions. (#8027)

CHANGES.md

@@ -57,6 +57,7 @@ Release Notes.
 * Fix unexpected deleting due to TTL mechanism bug for H2, MySQL, TiDB and PostgreSQL.
 * Add a GraphQL query to get OAP version, display OAP version in startup message and error logs.
 * Fix TimeBucket missing in H2, MySQL, TiDB and PostgreSQL bug, which causes TTL doesn't work for `service_traffic`.
+* Fix TimeBucket missing in ElasticSearch and provide compatible `storage2Entity` for previous versions.
 * Fix ElasticSearch implementation of `queryMetricsValues` and `readLabeledMetricsValues` doesn't fill default values
   when no available data in the ElasticSearch server.
 

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/manual/service/ServiceTraffic.java

@@ -100,7 +100,10 @@ public class ServiceTraffic extends Metrics {
             serviceTraffic.setName((String) dbMap.get(NAME));
             serviceTraffic.setNodeType(NodeType.valueOf(((Number) dbMap.get(NODE_TYPE)).intValue()));
             serviceTraffic.setGroup((String) dbMap.get(GROUP));
-            serviceTraffic.setTimeBucket(((Number) dbMap.get(TIME_BUCKET)).longValue());
+            // TIME_BUCKET column could be null in old implementation, which is fixed in 8.9.0
+            if (dbMap.containsKey(TIME_BUCKET)) {
+                serviceTraffic.setTimeBucket(((Number) dbMap.get(TIME_BUCKET)).longValue());
+            }
             return serviceTraffic;
         }