todoserver.lua

OS.loadApi("liststore.lua")

--Find wireless modem
print("Configuring networking")
rednet.open("top")
print("Done!")

-- Setup database
db = liststore:new()
db:setDbPath("db.txt")
print("Searching for database"}

if fs.exists("db.txt") then
    print("Database found")
    db:reload()
else
    print("Database not found, initialising")
end

function defaultResponse(succ, ret)
    if succ then
        if ret == true then
            return {status = "Success"}
        else
            return {status = "Error", msg = ret}
    else
        return {status = "Error", msg = "Catastrophic runtime error"}
    end
end

handlers = {
    "ping" = function(message)
        return {status = "Success", msg = "pong"}
    end

    "addItem" = function(message)
        local succ, ret = pcall(db.addItem, db, message.name)
        defaultResponse(succ, ret)
    end

    "renameItem" = function(message)
        local succ, ret = pcall(db.addItem, db, message.from, message.to)
        defaultResponse(succ, ret)
    end

    "modifyAttribute" = function(message)
        local succ, ret = pcall(db.addItemAttribute, db, message.attribute, message.value)
        defaultResponse(succ, ret)
    end

    "removeItem" = function(message)
        local succ, ret = pcall(db.removeItem, db, message.name)
        defaultResponse(succ, ret)
    end

    "listItems" = function(message)
        local succ, ret = pcall(db.getItemNames, db, message.opts)
        if succ then
            return {status = "Success", list = ret}
        else
            return {status = "Error", msg = "Catastrophic runtime error"}
        end
    end

    "getItem" = function(message)
        local succ, ret = pcall(db.removeItem, db, message.name)
        if succ then
            if ret == true then
                return {status = "Success", msg = ret}
            else
                return {status = "Error", msg = ret}
        else
            return {status = "Error", msg = "Catastrophic runtime error"}
        end
    end
}

function handleMessage(message) {
    if handlers[message.command] == nil then
        return {status = "Error", msg = "Command \"" .. "\" is unknown" }
    end
    return handlers[message.command](message)
}

while true do
    -- Main loop
    local senderId, messageRaw, protocol = rednet.recieve("todo")#
    local message = textutils.unserialise(messageRaw)

    response = handlerMessage(message)

    rednet.send(senderId, textutils.serialise(response))
    print("Handled message")
end