From 64b68fb3a2e5cc01f5a168e3864f18ad34fa91df Mon Sep 17 00:00:00 2001
From: qianlei <qianlei666@gmail.com>
Date: Wed, 29 Mar 2023 16:32:38 +0800
Subject: [PATCH] fix: Change listener to follower or change follower to
 listener is not supported.

---
 .../apache/ratis/server/impl/RaftServerImpl.java | 16 ++++++++++++++++
 .../ratis/server/impl/LeaderElectionTests.java   |  3 +++
 2 files changed, 19 insertions(+)

diff --git a/ratis-server/src/main/java/org/apache/ratis/server/impl/RaftServerImpl.java b/ratis-server/src/main/java/org/apache/ratis/server/impl/RaftServerImpl.java
index 9204faf68c..33f6b4b3dc 100644
--- a/ratis-server/src/main/java/org/apache/ratis/server/impl/RaftServerImpl.java
+++ b/ratis-server/src/main/java/org/apache/ratis/server/impl/RaftServerImpl.java
@@ -1245,6 +1245,22 @@ public CompletableFuture<RaftClientReply> setConfigurationAsync(SetConfiguration
         return pending.getFuture();
       }
 
+      // change listener to follower or change follower to listener is not supported yet
+      for (RaftPeer server : serversInNewConf) {
+        for (RaftPeer currentListener : current.getAllPeers(RaftPeerRole.LISTENER)) {
+          if (Objects.equals(currentListener.getId(), server.getId())) {
+            throw new SetConfigurationException("change listener to follower is not supported yet");
+          }
+        }
+      }
+      for (RaftPeer listener : listenersInNewConf) {
+        for (RaftPeer currentServer : current.getAllPeers(RaftPeerRole.FOLLOWER)) {
+          if (Objects.equals(currentServer.getId(), listener.getId())) {
+            throw new SetConfigurationException("change follower to listener is not supported yet");
+          }
+        }
+      }
+
       getRaftServer().addRaftPeers(serversInNewConf);
       getRaftServer().addRaftPeers(listenersInNewConf);
       // add staging state into the leaderState
diff --git a/ratis-server/src/test/java/org/apache/ratis/server/impl/LeaderElectionTests.java b/ratis-server/src/test/java/org/apache/ratis/server/impl/LeaderElectionTests.java
index dc22e27436..fcfbcd5ec1 100644
--- a/ratis-server/src/test/java/org/apache/ratis/server/impl/LeaderElectionTests.java
+++ b/ratis-server/src/test/java/org/apache/ratis/server/impl/LeaderElectionTests.java
@@ -44,6 +44,7 @@
 import org.apache.ratis.util.TimeDuration;
 import org.apache.ratis.util.Timestamp;
 import org.junit.Assert;
+import org.junit.Ignore;
 import org.junit.Test;
 import org.slf4j.Logger;
 
@@ -430,6 +431,7 @@ public void testRemoveListener() throws Exception {
   }
 
   @Test
+  @Ignore("not supported")
   public void testChangeFollowerToListener() throws Exception {
     try(final MiniRaftCluster cluster = newCluster(3)) {
       cluster.start();
@@ -453,6 +455,7 @@ public void testChangeFollowerToListener() throws Exception {
   }
 
   @Test
+  @Ignore("not supported")
   public void testChangeListenerToFollower() throws Exception {
     try(final MiniRaftCluster cluster = newCluster(2, 1)) {
       cluster.start();