Added informative return value to vl_client.send_message

api.lua

@@ -16,7 +16,7 @@ vl_client = {
 -- data: table to be sent to server, must be json serialisable
 local function send_data(data)
 	-- TODO: Should channel ever be nil?
-	if not channel then return end
+	if not vl_client.is_active then return end
 
 	local string_data = minetest.write_json(data)
 	--minetest.debug("Sending data to server:", string_data)
@@ -27,7 +27,7 @@ end
 -- opname: the name of the category of this message
 -- message: any json-serialisable object (not necessarily table)
 function vl_client.send_message(opname, message)
-	send_data({opname, message})
+	return send_data({opname, message})
 end
 
 -- ON MESSAGE RECEIVED

ping.lua

@@ -4,7 +4,10 @@ minetest.register_chatcommand("ping", {
 	params = "<message>",
 	description = "pings the server from the client",
 	func = function(param)
-        vl_client.send_message("ping", {type="request", content=param})
+        local send_status = vl_client.send_message("ping", {type="request", content=param})
+        if not send_status then
+			return false, "Client: unable to send ping"
+        end
 		return true, "Client: pinged server: " .. param
 	end,
 })