Textbattery for awesome awful widget (modified version of textclock widget)

textbattery.lua

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-- @copyright 2009 Julien Danjou
---------------------------------------------------------------------------

local setmetatable = setmetatable
local os = os
local textbox = require("wibox.widget.textbox")
local capi = { timer = timer }

--- Text battery widget.
-- awful.widget.textbattery
local textbattery = { mt = {} }

--- Create a textbattery widget. It draws the battery state it is in a textbox.
function textbattery.new()
    local timeout = 30
    local w = textbox()
    local timer = capi.timer { timeout = timeout }
    timer:connect_signal("timeout", function() x=io.popen("acpitool -b | awk '{print $4,$5}'");b=x:read("*a");w:set_markup(string.sub(b, 0, string.len(b)-2)) end)
    timer:start()
    timer:emit_signal("timeout")
    return w
end

function textbattery.mt:__call(...)
    return textbattery.new(...)
end

return setmetatable(textbattery, textbattery.mt)

Note: this widget requires acpitool program. so install it before any action: sudo apt install acpitool

Now copy this widget in /usr/share/awesome/lib/awful/widget/ then import it in init.lua file and then use it in your rc.lua like so:

mytextbattery = awful.widget.textbattery()
right_layout:add(mytextbattery)