Networking issue

[alpine frost]

Hi, can someone send me guide for correct networking on 1.21? Migrated from 1.20.4 to 1.21, as described in blog (https://fabricmc.net/2024/04/19/1205.html), but have such error. Source code: https://github.com/Hunkarada/Nen
Related to error code is here: https://github.com/Hunkarada/Nen/blob/master/src/main/java/hunkarada/nen/common/network/packet/SyncPacket.java https://github.com/Hunkarada/Nen/blob/master/src/main/java/hunkarada/nen/common/register/NenModRegister.java

Error itself

[alpine frost]

LOOOOOOOL

THE WHOLE ERROR WAS BECAUSE OF MY PATHS

Caused by: java.lang.ClassCastException: class hunkarada.nen.common.network.packets.SyncPacket cannot be cast to class net.minecraft.network.packet.UnknownCustomPayload (hunkarada.nen.common.network.packets.SyncPacket and net.minecraft.network.packet.UnknownCustomPayload are in unnamed module of loader net.fabricmc.loader.impl.launch.knot.KnotClassLoader @42e26948)

this part

I renamed hunkarada.nen.common.network.packet.SyncPacket to hunkarada.nen.common.networks.packets.SyncPacket and it WORKS

stupid name collision, caused by ???

maybe this is because of mixin?

[alpine frost]

and

it's not resolved

I still need help with that

and this should not be paths related

[alpine frost]

it worked maybe because of another network error

because error was like (Invalid player data)

and it reproduced only once

oh, if I reconnect to server, it throws invalid player data

fixed issue with invalid player data, now only fails at encoding (old error)

so, it can't cast my SyncPacket class to UnknownCustomPayload

my class implements CustomPayload interface

and in blog of fabric (here https://fabricmc.net/2024/04/19/1205.html) it says, that it can be some strange cast errors, but cast() method in my code didn't work at all

so, why it tries to do so?

I can't do this manually, it's different classes from different packages

OMG IT WAS MORE STUPID THAN I THROUGHT

But, you may ask, how do you get the decoder if it’s not in Id? Good question. **The answer: you need to register it in ModInitializer on both ends (sender and receiver). **In fact, Fabric API will happily crash if you don’t before calling registerGlobalReceiver.

from blog

so basicly, I fucked up in registring things