In this example we are going to send data with GET and POST commands from Roblox to Node-Red, from there we can output to MQTT and do in-real-life things with it.

Proof-of-Concept (to examine) #

Download this Roblox Example baseplate and open it in studio

Roblox HTTP POST GET to Node-Red example v1.0.rbxl.zip #

1 bestand(en) 13.72 KB

Downloaden

Download this flow for node-red to communicate

FLOW:

[
    {
        "id": "eb8d1610d554dfc7",
        "type": "http in",
        "z": "f6407c7dd7ea01ac",
        "name": "ROBLOX switch (/led)",
        "url": "/led",
        "method": "post",
        "upload": false,
        "swaggerDoc": "",
        "x": 180,
        "y": 160,
        "wires": [
            [
                "567df5fdf351d99d",
                "110e1344595000bd"
            ]
        ]
    },
    {
        "id": "567df5fdf351d99d",
        "type": "debug",
        "z": "f6407c7dd7ea01ac",
        "name": "DEBUG",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": true,
        "complete": "payload",
        "targetType": "msg",
        "statusVal": "payload",
        "statusType": "auto",
        "x": 420,
        "y": 160,
        "wires": []
    },
    {
        "id": "97d9d9dc81b21f6e",
        "type": "http in",
        "z": "f6407c7dd7ea01ac",
        "name": "ROBLOX temp (/temp)",
        "url": "/temp",
        "method": "get",
        "upload": false,
        "swaggerDoc": "",
        "x": 180,
        "y": 260,
        "wires": [
            [
                "87d556486ff8231a"
            ]
        ]
    },
    {
        "id": "87e77ce02658d132",
        "type": "http response",
        "z": "f6407c7dd7ea01ac",
        "name": "ENDPOINT",
        "statusCode": "",
        "headers": {},
        "x": 610,
        "y": 260,
        "wires": []
    },
    {
        "id": "87d556486ff8231a",
        "type": "function",
        "z": "f6407c7dd7ea01ac",
        "name": "Random number",
        "func": "msg.payload = {\n    \"temp\": Math.round(Math.random() * 30)\n}\nreturn msg;",
        "outputs": 1,
        "timeout": "",
        "noerr": 0,
        "initialize": "",
        "finalize": "",
        "libs": [],
        "x": 410,
        "y": 260,
        "wires": [
            [
                "87e77ce02658d132"
            ]
        ]
    },
    {
        "id": "110e1344595000bd",
        "type": "http response",
        "z": "f6407c7dd7ea01ac",
        "name": "ENDPOINT",
        "statusCode": "",
        "headers": {},
        "x": 430,
        "y": 100,
        "wires": []
    },
    {
        "id": "c4bd0c10ed7c76ae",
        "type": "http in",
        "z": "f6407c7dd7ea01ac",
        "name": "ROBLOX wallclick (/wallclick)",
        "url": "/wallclick",
        "method": "get",
        "upload": false,
        "swaggerDoc": "",
        "x": 200,
        "y": 420,
        "wires": [
            [
                "7db8e1bf98e27a75",
                "dacb8d7f89d1abca"
            ]
        ]
    },
    {
        "id": "7db8e1bf98e27a75",
        "type": "debug",
        "z": "f6407c7dd7ea01ac",
        "name": "DEBUG",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": true,
        "complete": "payload",
        "targetType": "msg",
        "statusVal": "payload",
        "statusType": "auto",
        "x": 440,
        "y": 420,
        "wires": []
    },
    {
        "id": "dacb8d7f89d1abca",
        "type": "http response",
        "z": "f6407c7dd7ea01ac",
        "name": "ENDPOINT",
        "statusCode": "",
        "headers": {},
        "x": 450,
        "y": 360,
        "wires": []
    }
]

Note: Where to place scripts?

Server config #

game.ServerScriptService.ServerConfigModule

In this map we can place some global variable we can use in other scripts, make sure it is a ModuleScript, a normal “script” won’t work!

Create a modulescript with the name ServerConfigModule:

Contents:

local config = {}
print("Running: Roblox and Node-Red communication example.")

-- Server configuration variables
config.BaseURL = "http://raspberrypi.local:1880"

print("Communicating with IP: " .. config.BaseURL)

return config

HTTP GET data #

game.ServerScriptService.TemperatureScript

Now, to get the temperatures with a HTTP GET command, create a normal script in game.ServerScriptService named: TemperatureScript, with the contents:

local HttpService = game:GetService("HttpService")
-- Load config settings
local config = require(game.ServerScriptService.ServerConfigModule)

while true do
	-- Use a GET request to fetch the JSON data
	local jsonString = HttpService:GetAsync(config.BaseURL .. "/temp")   
	local data = HttpService:JSONDecode(jsonString);
	print("De temperatuur is: " .. data.temp)
	Workspace.Sign.SurfaceGui.SIGN.Text = data.temp
	wait(1)
end

This will pull the temperature with GET from your Node-red startpoint (with a random number generator as example)

If everything is working well you can press the play button and see the value on the wall/sign change every second.

HTTP GET to send data #

game.ServerScriptService.WallClickScript

Now, to send data when clicking on an object (in this example a wall) with a HTTP GET command, create a normal script in game.ServerScriptService named: WallClickScript, with the contents:

-- Load config settings
local config = require(game.ServerScriptService.ServerConfigModule)

Workspace.WallOn.ClickDetector.MouseClick:connect(function()
	http = game:GetService("HttpService")
	http:GetAsync(config.BaseURL .. "/wallclick?clicked=true")
end)

This will execute a GET command with data to your Node-red startpoint

If everything is working well you can press wall where the lever is mounted to, and see the value “clicked=true” back in node-red.

HTTP POST to send data #

To send data we need an interactive object such as a lever, in this case there is a “triggered” Interactscript at: workspace.Lever.Stick.Switchprompt

workspace.Lever.Stick.Switchprompt.Interactscript

contents:

local function OnTriggered()
	workspace.Lever.SwitchBF:Invoke()
end

workspace.Lever.Stick.SwitchPrompt.Triggered:Connect(OnTriggered)

To send data we need the PostAsync function, this is the SwitchScript in game.ServerScriptService

game.ServerScriptService.SwitchScript

Contents:

local Lever = workspace.Lever
local Stick = Lever.Stick
local SwitchBF = Lever.SwitchBF

local OriginalCFrame = Stick.CFrame
local Offset = CFrame.new(-0.74798584, -0.748016357, 0, 0, -0.999999881, 0, 0.999999881, 0, 0, 0, 0, 1)

-- Load settings from Script in ServerScriptService
local config = require(game.ServerScriptService.ServerConfigModule)

local function Switch()
	local ValueAtt = Lever:GetAttribute("Value")
	
	if ValueAtt == true then
		Lever:SetAttribute("Value", false)
		Stick.CFrame = Stick.CFrame:ToWorldSpace(Offset)	
		
		local http = game:GetService("HttpService")
		local api = config.BaseURL .. "/led"
		print(api)
		local auth = ""

		local data = {
			['data'] = 'LEDON'
		}
		local encodedData = http:JSONEncode(data)
		http:PostAsync(api, encodedData, Enum.HttpContentType.ApplicationJson, false)
		
		print("on")

	else
		Lever:SetAttribute("Value", true)
		Stick.CFrame = OriginalCFrame
		
		local http = game:GetService("HttpService")
		local api = config.BaseURL .. "/led"
		local auth = ""

		local data = {
			['data'] = 'LEDOFF'
		}
		local encodedData = http:JSONEncode(data)
		http:PostAsync(api, encodedData, Enum.HttpContentType.ApplicationJson, false)

		print("on")
	end
end

SwitchBF.OnInvoke = Switch

Now when you start the game and walk to the lever switch you see you can interact with it by pressing “E”:

You will see the messages in Node-Red:

Pullrate limits #

Please note the limits (for Live Games): #