feat: OF-2559 - surface session initialise timeout to a system property

i18n/src/main/resources/openfire_i18n.properties

@@ -1683,6 +1683,7 @@ system_property.xmpp.server.outgoing.max.threads=Minimum amount of threads in th
 system_property.xmpp.server.outgoing.min.threads=Maximum amount of threads in the thread pool that is used to establish outbound server-to-server connections
 system_property.xmpp.server.outgoing.threads-timeout=Amount of time after which idle, surplus threads are removed from the thread pool that is used to establish outbound server-to-server connections.
 system_property.xmpp.server.outgoing.queue=Maximum amount of outbound server-to-server connections that can be in process of establishment in the thread pool (surplus connections will be created on the calling thread, possibly / gracefully slowing down other operations considerably)
+system_property.xmpp.server.session.initialise-timeout=Maximum amount of time in seconds for an outbound S2S session to be initialised
 system_property.cluster-monitor.service-enabled=Set to true to send messages to admins on cluster events, otherwise false
 system_property.ldap.override.avatar=Set to true to save avatars in the local database, otherwise false
 system_property.xmpp.domain=The XMPP domain of this server. Do not change this property directly, instead re-run the setup process.

xmppserver/src/main/java/org/jivesoftware/openfire/session/LocalOutgoingServerSession.java

@@ -26,6 +26,7 @@
 import org.jivesoftware.openfire.server.OutgoingServerSocketReader;
 import org.jivesoftware.openfire.server.RemoteServerManager;
 import org.jivesoftware.openfire.server.ServerDialback;
+import org.jivesoftware.util.SystemProperty;
 import org.jivesoftware.util.TaskEngine;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -34,6 +35,8 @@
 import javax.annotation.Nonnull;
 import java.net.Socket;
 import java.net.SocketAddress;
+import java.time.Duration;
+import java.time.temporal.ChronoUnit;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.Map;
@@ -67,6 +70,16 @@ public class LocalOutgoingServerSession extends LocalServerSession implements Ou
 
     private static final Interner<JID> remoteAuthMutex = Interners.newWeakInterner();
 
+    /**
+     * Controls the S2S outgoing session initialise timeout time in seconds
+     */
+    public static final SystemProperty<Duration> INITIALISE_TIMEOUT_SECONDS = SystemProperty.Builder.ofType(Duration.class)
+        .setKey("xmpp.server.session.initialise-timeout")
+        .setDefaultValue(Duration.ofSeconds(5))
+        .setChronoUnit(ChronoUnit.SECONDS)
+        .setDynamic(true)
+        .build();
+
     private OutgoingServerSocketReader socketReader;
     private final Collection<DomainPair> outgoingDomainPairs = new HashSet<>();
 
@@ -254,7 +267,7 @@ private static LocalOutgoingServerSession createOutgoingSession(@Nonnull final D
             // Wait for the future to give us a session...
             sessionInitialiser = new NettySessionInitializer(domainPair, port, directTLS);
             // Set a read timeout (of 5 seconds) so we don't keep waiting forever
-            return (LocalOutgoingServerSession) sessionInitialiser.init().get(5000, TimeUnit.MILLISECONDS);
+            return (LocalOutgoingServerSession) sessionInitialiser.init().get(INITIALISE_TIMEOUT_SECONDS.getValue().getSeconds(), TimeUnit.SECONDS);
         }
         catch (Exception e)
         {