Fabric Integration

Fabric Integration

This guide explains how to integrate the Minecraft Networking API with Fabric clients.

Setup

Ensure the API is added as a dependency (see Setup). In your build.gradle, include:

dependencies {
    modImplementation 'net.fabricmc:fabric-api:0.92.0+1.20.5'
    implementation 'com.github.RazorPlay01:PacketHandler:1.1.0'
    include 'com.github.RazorPlay01:PacketHandler:1.1.0'
}

Creating a Custom Payload

Use a CustomPayload implementation to bridge the API with Fabric’s networking.

Example:

import com.github.razorplay.packet_handler.network.IPacket;
import com.github.razorplay.packet_handler.network.PacketTCP;
import com.google.common.io.ByteArrayDataInput;
import com.google.common.io.ByteStreams;
import io.netty.buffer.ByteBuf;
import net.minecraft.network.RegistryByteBuf;
import net.minecraft.network.codec.PacketCodec;
import net.minecraft.network.packet.CustomPayload;
import net.minecraft.util.Identifier;

public record FabricCustomPayload(IPacket packet) implements CustomPayload {
    public static final Id<FabricCustomPayload> CUSTOM_PAYLOAD_ID = new Id<>(Identifier.of("my_mod", "packets_channel"));
    
    public static final PacketCodec<RegistryByteBuf, FabricCustomPayload> CODEC = PacketCodec.tuple(
        new PacketCodec<ByteBuf, IPacket>() {
            @Override
            public IPacket decode(ByteBuf byteBuf) {
                try {
                    byte[] data = new byte[byteBuf.readableBytes()];
                    byteBuf.readBytes(data);
                    ByteArrayDataInput in = ByteStreams.newDataInput(data);
                    return PacketTCP.read(in);
                } catch (Exception e) {
                    System.err.println("Error decoding packet: " + e.getMessage());
                    return null;
                }
            }

            @Override
            public void encode(ByteBuf byteBuf, IPacket packet) {
                try {
                    byteBuf.writeBytes(PacketTCP.write(packet));
                } catch (Exception e) {
                    System.err.println("Error encoding packet: " + e.getMessage());
                }
            }
        },
        FabricCustomPayload::packet,
        FabricCustomPayload::new
    );

    @Override
    public Id<? extends CustomPayload> getId() {
        return CUSTOM_PAYLOAD_ID;
    }
}

Registering Packets

In your mod’s initializer, register packets and the payload type:

import net.fabricmc.api.ClientModInitializer;
import net.fabricmc.fabric.api.client.networking.v1.ClientPlayNetworking;
import net.fabricmc.fabric.api.networking.v1.PayloadTypeRegistry;

public class MyMod implements ClientModInitializer {
    @Override
    public void onInitializeClient() {
        PacketTCP.registerPackets(MyPacket.class);
        PayloadTypeRegistry.playS2C().register(FabricCustomPayload.CUSTOM_PAYLOAD_ID, FabricCustomPayload.CODEC);
        PayloadTypeRegistry.playC2S().register(FabricCustomPayload.CUSTOM_PAYLOAD_ID, FabricCustomPayload.CODEC);

        ClientPlayNetworking.registerGlobalReceiver(FabricCustomPayload.CUSTOM_PAYLOAD_ID, (payload, context) -> {
            IPacket packet = payload.packet();
            if (packet instanceof MyPacket myPacket) {
                context.client().execute(() -> {
                    System.out.println("Received: " + myPacket.getMessage());
                });
            }
        });
    }
}

Sending Packets

Send packets from the client to the server:

ClientPlayNetworking.send(new FabricCustomPayload(new MyPacket("Hello from client!")));