textbox_cmd.lua

-- textbox_cmd: a textbox that executes a command regularly. {{{
-- Execute command and return its output.
function execute_command(command)
   local fh = io.popen(command)
   local r = {}
   for i in fh:lines() do
      r[#r+1] = i
   end
   io.close(fh)
   return r
end

local textbox_cmd = { mt = {} }
--- Create a textbox_cmd widget.
-- If the cmd output changes, a note gets displayed.
-- @param cmd The cmd to run.
-- @param markup The markup string to be used with string.format (%s).
-- @param timeout Timeout to run the cmd again. Default is 60 seconds.
-- @return A textbox widget.
function textbox_cmd.new(cmd, markup, timeout, report_changes)
    local markup = markup or '%s'
    local timeout = timeout or 60
    local report_changes = report_changes or false

    local w = wibox.widget.textbox()
    local tooltip = awful.tooltip({
      objects = { w },
    })
    local last_result_str
    local timer = capi.timer { timeout = timeout }
    timer:connect_signal("timeout", function()
        local result = execute_command(cmd)
        local result_header = result[1]
        local result_str = table.concat(result, "\n")

        if report_changes then
            if last_result_str and last_result_str ~= result_str then
              -- awful.util.spawn("notify-send -u normal -t0 'cmd result changed' "..cmd..': from \n' .. last_result .. '\n to \n' .. result, {timeout=0})
                bnote("cmd result changed: " .. cmd .. ": from \n"
                  .. last_result_str .. "\n to \n" .. result_str, {timeout=0})
            end
            last_result_str = result_str
        end

        local markup_header = string.format(markup, result_header and awful.util.escape(result_header) or "")
        w:set_markup(markup_header)

        -- Attach a tooltip, if there's additional information (after line 1).
        if #result > 1 then
          local markup_tooltip = string.format(markup, awful.util.escape(result_str))
          tooltip:set_markup(markup_tooltip)
        end
    end)
    timer:start()
    timer:emit_signal("timeout")
    return w
end
function textbox_cmd.mt:__call(...)
    return textbox_cmd.new(...)
end
textbox_cmd = setmetatable(textbox_cmd, textbox_cmd.mt)
-- }}}