added module for screen brightness

widgets/brightness_linux.lua

@@ -0,0 +1,39 @@
+-- template for asynchronous widet types
+-- Copyright (C) 2019  Nguyễn Gia Phong <[email protected]>
+--
+-- This file is part of Vicious.
+--
+-- Vicious is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as
+-- published by the Free Software Foundation, either version 2 of the
+-- License, or (at your option) any later version.
+--
+-- Vicious is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with Vicious.  If not, see <https://www.gnu.org/licenses/>.
+
+local helpers = require("vicious.helpers")
+local spawn = require("vicious.spawn")
+local gears = require("gears")
+
+local brightness_linux = {}
+
+function brightness_linux.async(format, warg, callback)
+    local cmd = "brightnessctl -m"
+
+    local function parse(response)
+    	-- extract percentage which incldues '%' at the end
+		response = gears.string.split(response, ',')[4]
+		-- remove '%' at the end
+		response = response:sub(1, response:len()-1)
+		return {response}
+    end
+
+    spawn.easy_async(cmd, function(stdout) callback(parse(stdout)) end)
+end
+
+return helpers.setasyncall(brightness_linux)