node_exporter textfile generator for Gentoo repository timestamps

repo_timestamp

#!/usr/bin/env python

import os
from os.path import exists, join
import time
import sys

import portage
from portage.const import TIMESTAMP_FORMAT
from portage.repository.config import RepoConfig


STDOUT = '/dev/stdout'


def _output_repo_timestamp(repository: RepoConfig, dest: str) -> None:
    timestamp_file = join(repository.location, "metadata/timestamp.chk")
    if not exists(timestamp_file):
        return

    with open(timestamp_file, 'r', encoding='UTF-8') as f:
        timestamp = time.strptime(f.read().strip(), TIMESTAMP_FORMAT)
        epoch_timestamp = int(time.mktime(timestamp))

    with open(dest, 'a', encoding='UTF-8') as f:
        f.write(
            f"repo_timestamp{{name=\"{repository.name}\"}} {epoch_timestamp}\n"
        )


if __name__ == '__main__':
    repos = portage.portdb.settings.repositories

    if len(sys.argv) <= 1:
        print(f"Usage: {sys.argv[0]} file")
        sys.exit(0)

    if sys.argv[1] == '-':
        OUTFILE = STDOUT
    else:
        OUTFILE = sys.argv[1]

    if OUTFILE != '/dev/stdout' and exists(OUTFILE):
        # We want to flush away any old values
        os.unlink(OUTFILE)

    for repo in repos:
        _output_repo_timestamp(repo, OUTFILE)