Support TransportVersions for ViewMetadata serialization

Author: craigtaverner

server/src/main/resources/transport/definitions/referable/esql_views.csv

@@ -0,0 +1 @@
+9177000

server/src/main/resources/transport/upper_bounds/9.2.csv

@@ -1 +1 @@
-roles_security_stats,9176000
+esql_views,9177000

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/plugin/EsqlPlugin.java

@@ -94,6 +94,7 @@
 import org.elasticsearch.xpack.esql.view.TransportGetViewAction;
 import org.elasticsearch.xpack.esql.view.TransportListViewsAction;
 import org.elasticsearch.xpack.esql.view.TransportPutViewAction;
+import org.elasticsearch.xpack.esql.view.ViewMetadata;
 import org.elasticsearch.xpack.esql.view.ViewService;
 
 import java.lang.invoke.MethodHandles;
@@ -376,6 +377,7 @@ public List<NamedWriteableRegistry.Entry> getNamedWriteables() {
 
         entries.add(ExpressionQueryBuilder.ENTRY);
         entries.add(PlanStreamWrapperQueryBuilder.ENTRY);
+        entries.add(ViewMetadata.ENTRY);
 
         entries.addAll(ExpressionWritables.getNamedWriteables());
         entries.addAll(PlanWritables.getNamedWriteables());

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/view/ViewMetadata.java

@@ -7,9 +7,9 @@
 package org.elasticsearch.xpack.esql.view;
 
 import org.elasticsearch.TransportVersion;
-import org.elasticsearch.TransportVersions;
 import org.elasticsearch.cluster.AbstractNamedDiffable;
 import org.elasticsearch.cluster.metadata.Metadata;
+import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.xcontent.ChunkedToXContentHelper;
@@ -30,6 +30,8 @@
  */
 public final class ViewMetadata extends AbstractNamedDiffable<Metadata.ClusterCustom> implements Metadata.ClusterCustom {
     public static final String TYPE = "esql_view";
+    public static final NamedWriteableRegistry.Entry ENTRY = new NamedWriteableRegistry.Entry(ViewMetadata.class, TYPE, ViewMetadata::new);
+    private static final TransportVersion ESQL_VIEWS = TransportVersion.fromName("esql_views");
 
     static final ParseField VIEWS = new ParseField("views");
 
@@ -65,8 +67,7 @@ public Map<String, View> views() {
 
     @Override
     public TransportVersion getMinimalSupportedVersion() {
-        // TODO set this to something sane, perhaps once the new TransportVersion mechanism is in place
-        return TransportVersions.INDEX_SOURCE;
+        return ESQL_VIEWS;
     }
 
     @Override