LogService.MessageOut not working on Roblox Player

Bug Reports Engine Bugs
#1

Reproduction Steps

1) Put this on ServerScriptService:

local LogService = game:GetService("LogService")

LogService.MessageOut:Connect(function(Message, Type)
	print('***Message, Type', Message, Type)
end)

print('PRINT SERVER')
warn('WARN SERVER')
error('ERROR SERVER')

  1. When run it on Studio, it’s working:

    image
    image869×181 29.7 KB

  2. But if I run the same in Roblox Player, it’s not working:

    image
    image1011×250 44.1 KB


Expected Behavior

I need to intercept warning messages on the server script.

Actual Behavior

It only works inside Studio.

----------

Issue Area: Engine
Issue Type: Other
Impact: High
Frequency: Constantly

6 Likes
#2

I was able to reproduce this issue, and am investigating the cause. Do you know if this is a new issue?

3 Likes
#3

No, that’s the first time I’m testing MessageOut for real.

2 Likes
#4

This has been an on-going issue for years. You can probably find other posts about this behavior relatively easily.

2 Likes
#5

This was intentional behavior I believe, if you print/warn/error/anything that writes to stdout in a MessageOut callback it would become recursive

#6

Not only that, there are ways to make LogService or ScriptContext recursive, but this isn’t related to the issue.

1 Like
#7

However, this does function (IE: the event fires and prints), in Studio. The issue is specifically with the Roblox live server.

1 Like
#8

I’m able to repro this but found that it just ignores prints from the event handler in a live game. The event is still fired. IIRC I saw in a release notes a while ago that printing was allowed from MessageOut where it wasn’t previously- maybe this is related to that change?

#9

You still running into this? I can’t repro:

image

For reference, here is my script (includes a check to avoid reentrancy):

game.LogService.MessageOut:Connect(function(msg, ty)
	if string.find(msg, "Got") then
		return
	end
	print("Got:", msg, ty)
end)

print("PRINT SERVER")
warn("WARN SERVER")
error("ERROR SERVER")
#10

Ran into this today, works in Studio but not live.

local LogService = game:GetService('LogService')

local messageTypeMap = {
	[Enum.MessageType.MessageWarning] = ' Warning:',
	[Enum.MessageType.MessageError] = ' Error:',
	[Enum.MessageType.MessageInfo] = ''
}

local function onMessageOut(message: string, messageType: Enum.MessageType, timestamp: number?)
	if messageType == Enum.MessageType.MessageOutput then return end
	timestamp = timestamp or workspace:GetServerTimeNow()
	print(`{timestamp}{messageTypeMap[messageType]} {message}`)
end

LogService.MessageOut:Connect(onMessageOut)
for _, log in LogService:GetLogHistory() do onMessageOut(log.message, log.messageType, log.timestamp) end

EDIT:
This claim seems correct: LogService doesn't work online - #4 by AlreadyPro

1 Like
#11

If you run exactly my code above (in a Script in ServerScriptService) does it work? The above screenshot by me is running in a live server.

#12

It does, and mine actually does too, in a fresh place. I may have overlooked something, but it doesn’t matter much as prints/warns/errors from within the function aren’t of much use anyways. What’s important is that it does pick everything up.

#13

Does it not in some other place?

What is it not picking up?

I remain unable to repro any issues (as of 6 days ago when I last took a look at this and replied).

#14

Correct, in some other place neither yours nor mine works (in terms of printing):

image
image776×357 86.2 KB

It works in Studio but not live.

Because of an NDA I cannot share further details about this place, I’m sorry. I will say that the place also uses ScriptContext.Error in another script, and that is the only somewhat related thing I can think of.

It is picking up everything, I might have worded it oddly.