More pythonic version

spec.py

#!/bin/env python3

import curses
import curses.ascii
import datetime
import humanize
import psutil


def main(screen):
    screen.timeout(1000)
    curses.curs_set(0)

    # make sure to use transparent background, if possible
    curses.use_default_colors()

    curses.init_pair(1, curses.COLOR_MAGENTA, -1)
    H1 = curses.color_pair(1) | curses.A_STANDOUT | curses.A_BOLD
    curses.init_pair(2, curses.COLOR_GREEN, -1)
    H2 = curses.color_pair(2) | curses.A_BOLD
    curses.init_pair(3, curses.COLOR_WHITE, -1)
    H3 = curses.color_pair(3)

    while True:
        screen.clear()
        screen.addstr("++SYSTEM INFO++\n",
            H1)


        screen.addstr(" DATE AND TIME\n",
            H2)

        time_now = datetime.datetime.now()
        time_now_rounded = time_now.replace(microsecond=0)

        screen.addstr("  {}\n\n".format(time_now_rounded),
            H3)


        screen.addstr(" UPTIME\n",
            H2)

        boot_time = datetime.datetime.fromtimestamp(psutil.boot_time())
        boot_time_rounded = boot_time.replace(microsecond=0)
        uptime = time_now_rounded - boot_time_rounded        

        screen.addstr("  {} ({} s)\n\n".format(uptime, int(uptime.total_seconds())),
            H3)


        screen.addstr(" SYSTEM INFO\n",
            H2 | curses.A_BOLD)

        sys_info = psutil.os.uname()
        screen.addstr("  OS: {0.sysname}\n  Kernel: {0.release}\n  Arch: {0.machine}\n  Hostname: {0.nodename}\n\n".format(sys_info),
            H3)

        
        screen.addstr(" CPU INFO\n",
            H2)

        screen.addstr("  Cores: {}/{}\n".format(psutil.cpu_count(logical=False),
                                                psutil.cpu_count(logical=True)),
            H3)
        try:
            # This method is new in psutil version 5.1.0
            cpu_freq = psutil.cpu_freq()
            screen.addstr("  Min/Max: {0.min}/{0.max} MHz\n".format(cpu_freq),
                H3)
        except:
            pass
        screen.addstr("  Utilization: {}%\n\n".format(psutil.cpu_percent()),
            H3)


        screen.addstr(" MEMORY INFO\n",
            H2)

        mem_info = psutil.virtual_memory()
        screen.addstr("  {0} / {1} ({2:.1%})\n\n".format(humanize.naturalsize(mem_info.used, binary=True),
                                               humanize.naturalsize(mem_info.total, binary=True),
                                               float(mem_info.used)/mem_info.total),
            H3)
        
        
        screen.addstr(" PROCESSES\n",
            H2 | curses.A_BOLD)
        pid_info = psutil.pids()
        screen.addstr("  Count: {}".format(len(pid_info)),
            H3)



        # quit when pressing ESCAPE or RETURN/ENTER or "Q"
        key = screen.getch()
        if key in [27,
                   10,
                   ord("q"),
                   ord("Q")]:
            break


curses.wrapper(main)