dns_server.lua

rednet.open("right")

print("DNS server started")

local dnsTable = {}

local function registerComputer(name, id)
    if dnsTable[name] then
        print("Registration failed: Name already registred")
        return false
    end

    dnsTable[name] = id
    print("Registation successful")
    print("PC: " .. name .. " ID: " .. id)

    return true
end


local function getComputerID(name)
    return dnsTable[name]
end


local function getAllComputers()
    return dnsTable
end


while true do
    local senderID, message, protocol = rednet.receive()
    local data = textutils.unserialise(message)

    if protocol == "dns_register" then
        if data and data.name and data.id then
            if registerComputer(data.name, data.id) then
                rednet.send(senderID, "Registation has been successful", "dns_ack")
            else
                rednet.send(senderID, "Registration failed: Name already registered", "dns_ack")
            end
        end
    elseif protocol == "dns_list" then
        local allComputers = getAllComputers()
        local listMessage = textutils.serialize(allComputers)
        rednet.send(senderID, listMessage, "dns_list_response")
    end
end