HOWTO: Inter-plugin communication

NiLSPACE · 10-22-2013, 09:40 PM

(10-22-2013, 09:39 PM)bearbin Wrote: Easiest thing to do is probably concat the table and resurrect it on the other side, asumming it's full of strings or ints.

It's full of functions Wink

bearbin · 10-22-2013, 11:05 PM

Oh, can't do that. Maybe store then as strings instead that can be called through IPC?

NiLSPACE · 10-22-2013, 11:10 PM

Well as you could maybe see in my Login plugin I can't do that. The functions in that table are specific for that table and can't be used outside it. You can compare it with a World or Player object.

FakeTruth · 10-22-2013, 11:46 PM

You cannot pass functions as it is right now

NiLSPACE · (This post was last modified: 10-22-2013, 11:50 PM by NiLSPACE.)

Yea I know, but you can pass userdata. And with my 'Login' plugin I have a table with functions in it where I keep my passwords. So I was wondering if I could somehow convert the table to userdata so it could be passable. This is the code:

function LoadPasswords(Path)
    local File = io.open(Path)
    local Table = {}
    if File then
        for I in File:lines() do
            local Split = StringSplit(I, ";")
            Table[Split[1]] = Split[2]
        end
        File:close()
    else
        local File = io.open(Path, "w")
        File:write()
        File:close()
    end
    local Object = {}
    function Object:GetPassFromPlayer(PlayerName)
        if Table[PlayerName] ~= nil then
            return true, Table[PlayerName]
        end
        return false
    end
     
    function Object:AddPass(PlayerName, Password)
        if Table[PlayerName] == nil then
            Table[PlayerName] = md5(Password)
            return true
        end
        return false
    end
     
    function Object:RemovePlayer(PlayerName)
        if Table[PlayerName] ~= nil then
            Table[PlayerName] = nil
            return true
        end
        return false
    end
     
    function Object:ChangePass(PlayerName, NewPassword)
        if Table[PlayerName] ~= nil then
            Table[PlayerName] = md5(NewPassword)
            return true
        end
        return false
    end
     
    function Object:PlayerExists(PlayerName)
        if Table[PlayerName] ~= nil then
            return true
        end
        return false
    end
     
    function Object:ReturnTable()
        return Table
    end
     
    function Object:Save()
        local File = io.open(Path, "w")
        for I, k in pairs(Table) do
            File:write(I .. ";" .. k .. "\n")
        end
        File:close()
    end
    return Object
end

FakeTruth · 10-23-2013, 12:59 AM

Yeah that's not gonna work Sad

You will have to make those Object functions global so other plugins can access them.

Use some kind of key to identify the Objects, this could be the player name and pass that key to the functions. You will need to keep track of the Objects in your plugin yourself.

I suppose you would like to call LoadPasswords() from another plugin? And then the other plugin will receive this Object containing functions.
To still have the same functionality without passing tables around you need to restructure some things.

local AllLoadedStuff = {}
 
function LoadPasswords(path)
    -- ... do stuff
    -- Create a unique key
    AllLoadedStuff[Key] = WhateverYouLoaded
    return Key
end
 
-- Former Object:GetPassFromPlayer
function GetPassFromPlayer(Key, PlayerName)
    local Object = AllLoadedStuff[Key];
     
    -- Still use Object functions
    return Object:GetPassFromPlayer(PlayerName)
     
    -- Or copy everything in here
    if Table[PlayerName] ~= nil then
            return true, Table[PlayerName]
    end
    return false
end

Not sure if it's clear what I mean? Tongue

NiLSPACE · 10-23-2013, 03:50 AM

Yes I think I know what you mean, but isn't there a way to create a userdata object? just like the cPlayer or cWorld object since that can be passed.

FakeTruth · 10-23-2013, 04:04 AM

In C++, yes. But that userdata is always shared data and therefore not thread safe. Not to mention that you still cannot store Lua functions in them, you would still have the same limitations as when you would simply send your table as a string like bearbin suggests.

xoft · 10-23-2013, 05:43 AM

Anyway, why would you want to make so much communication? It's inherently slow, so you can't be doing much through it.

bearbin · 10-23-2013, 05:46 AM

I thought it wasn't _that_ slow. I thought we benchmarked it to do 10000 things per tick on debug and it was fine?