history.py

import pickle
from os import mkdir, path, stat, listdir
from datetime import datetime

class CrashHistory():
    def __init__(self, backupstore):
        self.backupstore = backupstore + "/CrashFsBackups"
        CrashHistory.mkdirs(self.backupstore)

    @staticmethod
    def mkdirs(dirname):
        if not path.exists(dirname):
            mkdir(dirname)

    def add_to_history(self, state, version):
        dirname = self.backupstore + "/" + version
        filename = dirname + "/history.pkl"

        CrashHistory.mkdirs(dirname)
        
        with open(filename, "wb") as fd:
            pickle.dump(state, fd)

    def get_latest_history(self, version):
        filename = self.backupstore + "/" + version + "/history.pkl"

        if not path.exists(filename):
            return None
        
        with open(filename, "rb") as fd:
            backup = pickle.load(fd)

        return backup

    def get_version_date(self, version):
        filename = self.backupstore + "/" + version + "/history.pkl"

        if not path.exists(filename):
            return None

        return datetime.fromtimestamp(stat(filename).st_mtime).strftime("%d/%m/%Y, %H:%M:%S")

    def get_all_versions(self):
        if not path.exists(self.backupstore):
            return []

        return listdir(self.backupstore)