Blynk App for my OpenWrt-enabled router. https://www.hackster.io/vshymanskyy/android-ios-app-to-access-your-openwrt-router-remotely-6c23c2

blynkmon.lua

#!/usr/bin/env lua

local socket = require("socket")
local use_ssl, ssl = pcall(require, "ssl")

local Blynk = require("blynk.socket")
local Timer = require("timer")
local http = require("socket.http")

assert(#arg >= 1, "Please specify Auth Token")
local auth = arg[1]

local blynk = Blynk.new(auth, {
  heartbeat = 50,
  -- log = print,
})

function exec_out(cmd)
  local file = io.popen(cmd)
  if not file then return nil end
  local data = file:read("*a")
  file:close()
  -- print("Run: "..cmd.." -> "..data)
  return data
end

function read_file(path)
  local file = io.open(path, "rb")
  if not file then return nil end
  local data = file:read("*a")
  file:close()
  -- print("Read: "..path.." -> "..data)
  return data
end

function getArpClients()
  return tonumber(exec_out("cat /proc/net/arp | grep br-lan | grep 0x2 | wc -l"))
end

function getUptime()
  return tonumber(exec_out("cat /proc/uptime | awk '{print $1}'"))
end

function getPublicIP()
  local body, code, headers, status = http.request("https://api.ipify.org")
  if code == 200 then
    return body
  end
  return ""
end

function getHddSpinning()
  local code = os.execute("smartctl --nocheck=standby --info /dev/sda > /dev/null")
  return (code == 0) and 1 or 0
end

function getHddStats()
  local out = exec_out("cat /proc/diskstats | grep 'sda ' | awk '{print $6, $10}'")
  local reads, writes = out:match("([^ ]+) +([^ ]+)")
  return reads, writes
end

function getCpuLoad()
  return tonumber(exec_out("top -bn1 | grep 'CPU:' | head -n1 | awk '{print $2+$4}'"))
end

function getRamUsage()
  return tonumber(exec_out("free | grep Mem | awk '{print ($2-$4)/$2 * 100.0}'"))
end

function getWanIF()
  return exec_out("source /lib/functions/network.sh; network_flush_cache; network_find_wan NET_IF; echo -n $NET_IF")
end

function getWanIP()
  local wanif = getWanIF()
  if wanif == "" then return "" end
  return exec_out("source /lib/functions/network.sh; network_get_ipaddr NET_ADDR " .. wanif .. "; echo $NET_ADDR")
end

function getWanRxBytes()
  local wanif = getWanIF()
  if wanif == "" then return 0 end
  return tonumber(read_file("/sys/class/net/" .. wanif .. "/statistics/rx_bytes"))
end

function getWanTxBytes()
  local wanif = getWanIF()
  if wanif == "" then return 0 end
  return tonumber(read_file("/sys/class/net/" .. wanif .. "/statistics/tx_bytes"))
end

function getActiveConnections()
  return tonumber(read_file("/proc/sys/net/netfilter/nf_conntrack_count"))
end

function getWiFiStatus()
  if string.find(exec_out("ubus call network.wireless status | jsonfilter -e '@.radio0.up'"), "true") then
    return 1
  else
    return 0
  end
end

local function connectBlynk()
  local host = "blynk.cloud"

  local sock = assert(socket.tcp())
  sock:setoption("tcp-nodelay", true)

  if use_ssl then
    print("Connecting Blynk (secure)...")
    sock:connect(host, 443)
    local opts = {
      mode = "client",
      protocol = "tlsv1_2"
    }
    sock = assert(ssl.wrap(sock, opts))
    sock:dohandshake()
  else
    print("Connecting Blynk...")
    sock:connect(host, 80)
  end

  -- tell Blynk to use this socket
  blynk:connect(sock)
end

--[[ WiFi control ]]

blynk:on("V20", function(param)
  if param[1] == "1" then
    os.execute("wifi up")
  else
    os.execute("wifi down")
  end
end)

--[[ Locking ]]

local isLocked = true

local function advLock()
  blynk:setProperty(30,"color","#D3435C") -- red
  blynk:setProperty(30,"label","Locked")
  isLocked = true
end

local function advUnlock()
  blynk:setProperty(30,"color","#23C48E") -- green
  blynk:setProperty(30,"label","Unlocked")
  isLocked = false
end

blynk:on("V30", function(param)
  if isLocked and param[1] == "10" then
    advUnlock()
  elseif not isLocked then
    advLock()
  end
end)

--[[ Reboot ]]

blynk:on("internal:dbg", function(param)
  if param[1] == "reboot" then
    os.execute("reboot")
  end
end)

--[[ Shell ]]

blynk:on("V35", function(param)
  if isLocked then
    blynk:virtualWrite(35, "Shell is LOCKED\n")
    return
  end
  local out = exec_out(param[1])
  blynk:virtualWrite(35, out)
end)


blynk:on("disconnected", function()
  print("Disconnected.")
  -- auto-reconnect after 5 seconds
  socket.sleep(5)
  connectBlynk()
end)

--[[ Timers ]]

local prev = { spin = -1 }

local tmr1 = Timer:new{interval = 5000, func = function()
  local tx = getWanTxBytes()
  local rx = getWanRxBytes()

  if prev.tx then
    local dtx = tx - prev.tx
    if prev.dtx ~= dtx then
      blynk:virtualWrite(1, dtx / 1024 / 1024)
      prev.dtx = dtx
    end
  end
  prev.tx = tx

  if prev.rx and prev.rx ~= rx then
    local drx = rx - prev.rx
    if prev.drx ~= drx then
      blynk:virtualWrite(2, drx / 1024 / 1024)
      prev.drx = drx
    end
  end
  prev.rx = rx

  local spin = getHddSpinning()
  if spin ~= prev.spin then
    blynk:virtualWrite(7, spin)
  end
  prev.spin = spin

  if spin then
    local rd, wt = getHddStats()

    if prev.rd then
      local drd = rd - prev.rd
      if prev.drd ~= drd then
        blynk:virtualWrite(8, drd)
        prev.drd = drd
      end
    end
    prev.rd = rd

    if prev.wt then
      local dwt = wt - prev.wt
      if prev.dwt ~= dwt then
        blynk:virtualWrite(9, dwt)
        prev.dwt = dwt
      end
    end
    prev.wt = wt
  end

  blynk:virtualWrite(4, getActiveConnections())
  blynk:virtualWrite(5, getCpuLoad())
  blynk:virtualWrite(6, getRamUsage())
  blynk:virtualWrite(10, getArpClients())
end}

local tmr2 = Timer:new{interval = 5*60*1000, func = function()
  blynk:virtualWrite(11, string.format("%.1f", getUptime()/60/60))
end}

blynk:on("connected", function(ping)
  print("Ready. Ping: " .. math.floor(ping*1000) .. "ms")

  blynk:virtualWrite(12, getWanIP())
  blynk:virtualWrite(13, getPublicIP())
  blynk:virtualWrite(20, getWiFiStatus())
end)

connectBlynk()

while true do
  blynk:run()
  tmr1:run()
  tmr2:run()
end

Hello,
I was one of your first backers on kickstarter and I'm very happy with the platform and how it developed.
If you have time can you please give me an advice on how to modify the part of this script here in order to bound a value read form CLI to a virtual pin like you do in this lua script?

This is more reliable for getting the current WAN IP address:

function getWanIP()
  return exec_out("source /lib/functions/network.sh; network_flush_cache; network_find_wan NET_IF; network_get_ipaddr NET_ADDR $NET_IF; echo $NET_ADDR")
end