Breaking change: Make ILoadBalancer guild-aware (#23)

Co-authored-by: Freya Arbjerg <[email protected]>

Author: duncte123

src/main/kotlin/dev/arbjerg/lavalink/client/LavalinkClient.kt

@@ -138,7 +138,7 @@ class LavalinkClient(val userId: Long) : Closeable, Disposable {
     @JvmOverloads
     fun getOrCreateLink(guildId: Long, region: VoiceRegion? = null): Link {
         if (!linkMap.containsKey(guildId)) {
-            val bestNode = loadBalancer.selectNode(region)
+            val bestNode = loadBalancer.selectNode(region, guildId)
             linkMap[guildId] = Link(guildId, bestNode)
         }
 
@@ -205,7 +205,7 @@ class LavalinkClient(val userId: Long) : Closeable, Disposable {
 
                 link.state = LinkState.CONNECTING
                 // The delay is used to prevent a race condition in Discord, causing close code 4006
-                link.transferNode(loadBalancer.selectNode(region = voiceRegion), delay = Duration.ofMillis(1000))
+                link.transferNode(loadBalancer.selectNode(region = voiceRegion, link.guildId), delay = Duration.ofMillis(1000))
             }
         }
     }

src/main/kotlin/dev/arbjerg/lavalink/client/loadbalancing/ILoadBalancer.kt

@@ -13,17 +13,18 @@ interface ILoadBalancer {
      * @see #selectNode(VoiceRegion)
      */
     fun selectNode(): LavalinkNode {
-        return selectNode(null)
+        return selectNode(null, null)
     }
 
     /**
      * Selects a node based on the criteria of the load balancer.
      * @param region A voice region may be provided to filter on the closest region to this node
+     * @param guildId The ID of the guild to be associated with the returned node
      *
      * @return The best node that matches the criteria
      * @throws RuntimeException when no nodes are available
      */
-    fun selectNode(region: VoiceRegion?): LavalinkNode
+    fun selectNode(region: VoiceRegion?, guildId: Long?): LavalinkNode
 
     /**
      * Adds a penalty provider to the load balancer.

src/main/kotlin/dev/arbjerg/lavalink/client/loadbalancing/builtin/DefaultLoadBalancer.kt

@@ -17,7 +17,7 @@ class DefaultLoadBalancer(private val client: LavalinkClient) : ILoadBalancer {
         penaltyProviders.remove(penaltyProvider)
     }
 
-    override fun selectNode(region: VoiceRegion?): LavalinkNode {
+    override fun selectNode(region: VoiceRegion?, guildId: Long?): LavalinkNode {
         val nodes = client.nodes
 
         // Don't bother calculating penalties if we only have one node.