Adjust versions for settings in follower requests

We recently added the ability for auto follow patterns and follower
requests to include settings overrides. This commit adjusts the
serialization versions on these requests.

Author: jasontedor

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ccr/action/PutAutoFollowPatternAction.java

@@ -5,6 +5,7 @@
  */
 package org.elasticsearch.xpack.core.ccr.action;
 
+import org.elasticsearch.Version;
 import org.elasticsearch.action.ActionRequestValidationException;
 import org.elasticsearch.action.ActionType;
 import org.elasticsearch.action.support.master.AcknowledgedRequest;
@@ -159,7 +160,9 @@ public Request(StreamInput in) throws IOException {
             remoteCluster = in.readString();
             leaderIndexPatterns = in.readStringList();
             followIndexNamePattern = in.readOptionalString();
-            settings = Settings.readSettingsFromStream(in);
+            if (in.getVersion().onOrAfter(Version.V_7_9_0)) {
+                settings = Settings.readSettingsFromStream(in);
+            }
             parameters = new FollowParameters(in);
         }
 
@@ -170,7 +173,9 @@ public void writeTo(StreamOutput out) throws IOException {
             out.writeString(remoteCluster);
             out.writeStringCollection(leaderIndexPatterns);
             out.writeOptionalString(followIndexNamePattern);
-            Settings.writeSettingsToStream(settings, out);
+            if (out.getVersion().onOrAfter(Version.V_7_9_0)) {
+                Settings.writeSettingsToStream(settings, out);
+            }
             parameters.writeTo(out);
         }
 

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ccr/action/PutFollowAction.java

@@ -6,6 +6,7 @@
 
 package org.elasticsearch.xpack.core.ccr.action;
 
+import org.elasticsearch.Version;
 import org.elasticsearch.action.ActionRequestValidationException;
 import org.elasticsearch.action.ActionResponse;
 import org.elasticsearch.action.ActionType;
@@ -173,7 +174,9 @@ public Request(StreamInput in) throws IOException {
             this.remoteCluster = in.readString();
             this.leaderIndex = in.readString();
             this.followerIndex = in.readString();
-            this.settings = Settings.readSettingsFromStream(in);
+            if (in.getVersion().onOrAfter(Version.V_7_9_0)) {
+                this.settings = Settings.readSettingsFromStream(in);
+            }
             this.parameters = new FollowParameters(in);
             waitForActiveShards(ActiveShardCount.readFrom(in));
         }
@@ -184,7 +187,9 @@ public void writeTo(StreamOutput out) throws IOException {
             out.writeString(remoteCluster);
             out.writeString(leaderIndex);
             out.writeString(followerIndex);
-            Settings.writeSettingsToStream(settings, out);
+            if (out.getVersion().onOrAfter(Version.V_7_9_0)) {
+                Settings.writeSettingsToStream(settings, out);
+            }
             parameters.writeTo(out);
             waitForActiveShards.writeTo(out);
         }