Home / Lua / Tutorials / Beginner / Server-client communication

The only way to communicate from server to client or vice versa is using the Network class.

Example

This simple example will print a message on any client that joins. We will use the functions Network:Send and Network:Subscribe.

Client

message = "Default message"
function RenderMessage()
	Render:DrawText(Render.Size / 2, message, Color(255, 255, 255))
end
Events:Subscribe("Render", RenderMessage)

function ClientFunction(sentMessage)
	message = sentMessage
end
-- Subscribe ClientFunction to the network event "Test".
Network:Subscribe("Test", ClientFunction)

Server

function ServerFunction(args)
	-- Call the network event "Test" for this player. The argument is a string.
	Network:Send(args.player, "Test", "Hello, client!")
end
Events:Subscribe("ClientModuleLoad", ServerFunction)

The ClientModuleLoad event is called on the server when all of a client's scripts are loaded, usually right after they join (or when a module is reloaded). This is a good time to send the client network messages. Otherwise, if you try to use Network:Send on the PlayerJoin event, their scripts may not have subscribed to the network event yet, and nothing will appear to happen.

More information

The client can use Network:Send just like the server can, it works exactly the same. With one difference: server functions that are subscribed to a network event have a second argument, the Player who sent the network event.

See also

Lua/Tutorials/Intermediate/A tank that shoots tanks