prune-cache.py

# SPDX-License-Identifier: MIT

import sys
import json
import datetime
import argparse
import pathlib


def parse_cache_date(datestr: str):
    yr, mo, day, type = datestr.split("-")
    date = datetime.date(int(yr), int(mo), int(day))
    return date


def prune_cache_file(infile: str, outfile: str, days_before_today):
    with open(infile, "r") as f:
        json_data = json.load(f)

    pruned = {}
    today = datetime.date.today()
    for key, value in json_data.items():
        date = parse_cache_date(key)
        delta = (today - date).days
        # print(f"{today} - {date}: delta={delta}")
        if delta > days_before_today:
            pruned[key] = value

    with open(outfile, "w") as dstf:
        json.dump(pruned, dstf, indent=1, sort_keys=True)


def main(argv=None):
    pruned_file = "./sst-data-cache-pruned.json"

    class CustomFormatter(
        argparse.ArgumentDefaultsHelpFormatter,
        argparse.RawDescriptionHelpFormatter,
    ):
        pass

    try:
        parser = argparse.ArgumentParser(
            description="""Cache-file pruner""",
            formatter_class=CustomFormatter,
        )
        parser.add_argument(
            "--verbose",
            "-v",
            action="store_true",
            help="""Process verbosely""",
        )
        parser.add_argument(
            "--days",
            "-d",
            type=int,
            default=180,
            help="""Prune limit: days before today -- """
            """most recent N days will be pruned out""",
        )
        parser.add_argument(
            "--inplace",
            "-I",
            action="store_true",
            default=False,
            help="""Write pruned result to input file, """
            """replacing it (out file param will be ignored)""",
        )
        parser.add_argument(
            "--out",
            "-o",
            type=pathlib.Path,
            default=pruned_file,
            help="""Write pruned result to this file""",
        )
        parser.add_argument(
            "--in",
            "-i",
            type=pathlib.Path,
            dest="infile",  # needed since "in" is a keyword
            default="./sst-data-cache.json",
            help="""Input cache file""",
        )
        args = parser.parse_args(argv)

        if args.inplace:
            args.out = args.infile
        prune_cache_file(args.infile, args.out, args.days)

    except RuntimeError as e:
        print(e)
        return 1


if __name__ == "__main__":
    sys.exit(main(sys.argv[1:]))