Differences

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--- tutorial:networking [2022/01/28 07:14] – [The concept of tracking and why you only see the highlighted block] solidblock
+++ tutorial:networking [2024/05/04 19:51] (current) – Call out the 1.20.5 networking section at the top so people can know to skip to it bluemeanial
@@ Line 2: / Line 2: @@
 It is recommended to use the new networking API described on this page.
 The old page can be [[tutorial:legacy:networking-v0|found here]].
+For the even newer networking API introduced at 1.20.5, read the [[#Networking in 1.20.5 | separate documentation below]].
 ====== Networking ======
@@ Line 13: / Line 15: @@
 Say you had a wand which highlights the block you are looking at to all nearby players.
 <code java [enable_line_numbers="true"]>
-class HighlightingWandItem extends Item {
+public class HighlightingWandItem extends Item {
     public HighlightingWand(Item.Settings settings) {
         super(settings)
@@ Line 78: / Line 80: @@
 </code>
-Next, we need to send the packet to the game client. First, you need to define an ''Identifier'' used to identify your packet. For this example our Identifier will be ''wiki_example:highlight_block''. In order to send the packet to the game client, you need to specify which player's game client you want to packet to be received by. Since the action is occurring on the logical server, we may upcast the ''player'' to a ''ServerPlayerEntity''.
+Next, we need to send the packet to the game client. First, you need to define an ''Identifier'' used to identify your packet. For this example our Identifier will be ''wiki_example:highlight_block''. In order to send the packet to the game client, you need to specify which player's game client you want the packet to be received by. Since the action is occurring on the logical server, we may upcast the ''player'' to a ''ServerPlayerEntity''.
+<code java>
+public class TutorialNetworkingConstants {
+    // Save the id of the packet so we can reference it later
+    public static final Identifier HIGHLIGHT_PACKET_ID = new Identifier("wiki_example", "highlight_block");
+}
+</code>
 To send the packet to the player, we will use some of the methods inside of ''ServerPlayNetworking''. We will use the following method inside of that class:
@@ Line 211: / Line 219: @@
 After this change, when you use the wand, your friend should also see the highlighted block on their own client.
-====== Advanced Networking topics ======
-The Networking system Fabric API supplies is very flexible and supports additional features other than just sending and receiving simple packets. As some of these more advanced topics are long, here are links to their specific pages:
+===== Networking in 1.20.5 =====
+Since 1.20.5, the logic of networking has been totally rewritten. In 1.20.5, you have to define a custom ''Payload''. First, define the payload that includes a ''BlockPos'':
-^ Networking Topic ^ Description ^
+<code java>
-| [[tutorial:networking:connection_events|Connection Network connection events]] | Events related to the the lifecycle of a connection to a client or server |
+public record BlockHighlightPayload(BlockPos blockPos) implements CustomPayload {
-| [[tutorial:networking:channel_events|Channel registration events]] | Events related to a server of client declaring the ability to receive a packet on a channel of a specific name |
+  public static final Id<BlockHighlightPayload> ID = CustomPayload.id("tutorial:block_highlight");
-| [[tutorial:networking:login|Login phase networking]]| Sending requests to a client during login; and allowing delay of login for a short amount of time |
+  public static final PacketCodec<PacketByteBuf, BlockHighlightPayload> CODEC = PacketCodec.tuple(BlockPos.PACKET_CODEC, BlockHighlightPayload::blockPos, BlockHighlightPayload::new);
-| [[tutorial:networking:dynamic_handlers|Dynamic registration of channel handlers]]| Allowing for a connection to receive a packet with a special handler |
+  // or you can also write like this:
+  // public static final PacketCodec<PacketByteBuf, BlockHighlightPayload> CODEC = PacketCodec.of((value, buf) -> buf.writeBlockPos(value.blockPos), buf -> new BlockHighlightPayload(buf.readBlockPos()));
+  @Override
+  public Id<? extends CustomPayload> getId() {
+    return ID;
+  }
+}
+</code>
+And then, register the receiver like this:
+<code java>
+PayloadTypeRegistry.playS2C().register(BlockHighlightPayload.ID, BlockHighlightPayload.CODEC);
+ClientPlayNetworking.registerGlobalReceiver(BlockHighlightPayload.ID, (payload, context) -> {
+  context.client().execute(() -> {
+    ClientBlockHighlighting.highlightBlock(client, target);
+  });
+});
+</code>
+Now, on the server side, you can send the packet to players like this:
+<code java>
+    public TypedActionResult<ItemStack> use(World world, PlayerEntity user, Hand hand) {
+        if (world.isClient()) return super.use(world, user, hand);
+        // ...
+        for (ServerPlayerEntity player : PlayerLookup.tracking((ServerWorld) world, target)) {
+            ServerPlayNetworking.send(player, new BlockHighlightPayload(blockPos));
+        }
+        return TypedActionResult.success(user.getHandStack(hand));
+    }
+</code>