install

#! /usr/bin/env python3

import os
import shutil

from string import Template
from subprocess import check_call
from subprocess import check_output

EXEC          = 'chrony-graph-loop'
SERVICE       = 'chrony-graph.service'
SYSTEM_DIR    = '/etc/systemd/system'
CONFIG        = 'chrony-graph.conf'
SAMPLE_CONFIG = 'chrony-graph.sample.conf'
CONFIG_DIR    = '/etc/chrony-graph'

CURRENT_DIR      = os.path.dirname(os.path.realpath(__file__))
EXEC_PATH        = os.path.join(CURRENT_DIR, EXEC)
SERVICE_TEMPLATE = os.path.join(CURRENT_DIR, SERVICE)
SERVICE_FILE     = os.path.join(SYSTEM_DIR, SERVICE)
CONFIG_FILE      = os.path.join(CONFIG_DIR, CONFIG)
USER             = check_output(['logname']).decode('utf-8').strip()

with open(SERVICE_TEMPLATE) as f:
    serviceTemplate = Template(f.read())

serviceFile = serviceTemplate.substitute(
    workingDirectory=CURRENT_DIR,
    execStart=EXEC_PATH,
    user=USER
)

with open(SERVICE_FILE, 'w') as f:
    f.write(serviceFile)

if not os.path.exists(CONFIG_FILE):
    os.makedirs(CONFIG_DIR, exist_ok=True)
    shutil.copy(SAMPLE_CONFIG, CONFIG_FILE)

check_call(['systemctl', 'daemon-reload'])
check_call(['systemctl', 'enable', '--no-pager', SERVICE])
check_call(['systemctl', 'restart', '--no-pager', SERVICE])
check_call(['systemctl', 'status', '--no-pager', SERVICE])