Refined Storage Bridge

local rs = peripheral.find("rsBridge")
if not rs then error("No RS Bridge attached!") end

local function chunkString(value, chunkSize)
    if not chunkSize then chunkSize = 10000 end
    local length = value:len()
    local total = math.ceil(length / chunkSize)
    local chunks = {}
    local i = 1
    for i=1,total do
        local pos = 1 + ((i - 1) * chunkSize)
        chunks[i] = value:sub(pos, pos + chunkSize - 1)
    end
    return total, chunks
end

local function main()
    print("Connecting to the socket server...")
    local socket, reason = http.websocket("ws://ws.cnml.de:8080")
    if not socket then error("Socket server could not be reached: "..reason) end
    print("Connection successful!")
    socket.send("{\"role\":\"rs\"}")

    local function handleRequest(parsed)
        if parsed.method == "energyusage" then
            return true, tostring(rs.getEnergyUsage())
        elseif parsed.method == "energystorage" then
            return true, tostring(rs.getEnergyStorage())
        elseif parsed.method == "listitems" then
            return true, textutils.serializeJSON(rs.listItems())
        elseif parsed.method == "listfluids" then
            return true, textutils.serializeJSON(rs.listFluids())
        end

        return false, ("Invalid method: "..parsed.method.."!")
    end

    local function sendResponse(id, result)
        local total, chunks = chunkString(result)
        for i, chunk in pairs(chunks) do
            socket.send(textutils.serializeJSON({ id = id, result = chunk, chunk = i, total = total }))
        end
    end

    local function handleMessage(message)
        local parsed, reason = textutils.unserializeJSON(message)
        if not parsed then print("Deserialization failed: "..reason..", in messsage "..message) return end

        if parsed.type == "request" then
            local success, result = handleRequest(parsed)
            if success then
                sendResponse(parsed.id, result)
            else
                printError("Error when answering", parsed.method, "method:", result)
            end
            return
        end

        printError("No handler for messages of type", parsed.type)
    end

    while true do
        local message, binary = socket.receive(1)
        if not not message and not binary then
            handleMessage(message)
        end
    end
end

while true do
    local status, err = pcall(main)
    if not status then
        printError("Uncaught error:", err)
        print("Sleeping for 5 seconds and retrying!")
        sleep(5)
    end
end