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Networking Library

This page documents network-variable and message helpers.

Overview

The networking library synchronises data between the server and clients. It wraps helpers so global variables can be stored in lia.net.globals and automatically replicated. It also supports chunked transfer of large tables between server and clients. Any value sent through this system is re-sent to players on spawn via PlayerInitialSpawn and must not contain functions (or tables that contain functions), as they cannot be serialised.

lia.net.readBigTable

Purpose

Registers a handler that rebuilds large tables sent over the network in multiple compressed chunks. Clients acknowledge each chunk so the sender can throttle transmission.

Parameters

  • netStr (string): Network message identifier to listen for.

  • callback (function): Function invoked when the table is fully received. On the server the signature is callback(ply, tbl), on the client it is callback(tbl).

Realm

Shared

Returns

  • nil: This function does not return a value.

Example Usage

-- Both server and client: install receiver
lia.net.readBigTable("MyData", function(a, b)
    if SERVER then
        local ply, data = a, b
        print("Server received table from", ply, data)
    else
        local data = a
        PrintTable(data)
    end
end)

lia.net.writeBigTable

Purpose

Splits a table into compressed chunks and streams it to one or more players. Used in conjunction with lia.net.readBigTable. Aborts if the table is not serialisable or cannot be compressed.

Parameters

  • targets (Player | Player[] | nil): Recipient(s); nil streams to all human players.

  • netStr (string): Network message identifier.

  • tbl (table): Data to send. Must be JSON-serialisable (no functions).

  • chunkSize (number | nil): Optional bytes per chunk (default 2048, clamped to the range 256–4096).

Realm

Server

Returns

  • nil: This function does not return a value.

Example Usage

local data = {foo = "bar", numbers = {1, 2, 3}}

-- Broadcast to everyone
lia.net.writeBigTable(nil, "MyData", data)

-- Send to one player with smaller chunks
lia.net.writeBigTable(player, "MyData", data, 1024)

checkBadType

Purpose

Recursively validates a value before it is networked, ensuring neither it nor any nested key or value is a function. Any disallowed value triggers lia.error with a translated message.

Parameters

  • name (string): Identifier for error reporting.

  • object (any): Value to inspect.

Realm

Server

Returns

  • boolean | nil: true if a disallowed type was found; otherwise nil.

Example Usage

if checkBadType("roundData", someTable) then
    return
end

setNetVar

Purpose

Stores a value in lia.net.globals and broadcasts the change, optionally restricting it to a receiver. Disallowed types are rejected, and no network message is sent if the value has not changed. The NetVarChanged hook is fired after successful updates.

Parameters

  • key (string): Name of the variable.

  • value (any): Value to store.

  • receiver (Player | Player[] | nil): Target player(s). nil broadcasts to everyone.

Realm

Server

Returns

  • nil: This function does not return a value.

Example Usage

-- Start a new round and store the winner
local nextRound = getNetVar("round", 0) + 1
setNetVar("round", nextRound)

local champion = DetermineWinner()

-- Only the winner receives this variable
setNetVar("last_winner", champion, champion)

hook.Run("RoundStarted", nextRound)

getNetVar

Purpose

Retrieves a value from lia.net.globals, returning a default if the key is unset.

Parameters

  • key (string): Variable name.

  • default (any): Fallback value if unset.

Realm

Shared

Returns

  • any: Stored value or the supplied default.

Example Usage

-- Inform new players of the current round and previous champion
hook.Add("PlayerInitialSpawn", "ShowRound", function(ply)
    local round = getNetVar("round", 0)
    ply:ChatPrint(("Current round: %s"):format(round))

    local lastWinner = getNetVar("last_winner")
    if IsValid(lastWinner) then
        ply:ChatPrint(("Last round won by %s"):format(lastWinner:Name()))
    end
end)