aswi2021vochomurka-gitlab/aswi2021vochomurka/service/file_manager.py @ 64ca87d0

import logging
import os
import time

from aswi2021vochomurka.model.Message import Message
from typing import TextIO

trans = str.maketrans({
    "/": "_",
    "\\": "_",
    ":": "_",
    "\"": "_",
    "$": "_",
    "*": "_",
    ".": "_"})


def create_filename(message: Message) -> str:
    """
    Create file name based on message data
    :param message: message
    :return: filename
    """
    name = "data/" + message.topic.translate(trans) + "/" + message.date + "_" + message.time + ".csv"
    return name


class FileManager:
    """
    Helper class for writing incoming message to files
    Each topic has created own instance of this class
    """
    topic: str
    lastUpdate: float
    file: TextIO

    def __init__(self, topic: str, message: Message):
        """
        Constructing new FileManager will create new file and write first message
        :param topic: topic
        :param message: message
        :except when creating new file fails
        """
        self.topic = topic
        logging.debug('opening file ' + self.topic)

        try:
            filename = create_filename(message)
            os.makedirs(os.path.dirname(filename), exist_ok=True)
            self.file = open(filename, "w+")
        except Exception as error:
            logging.warning(error)
            raise error
        self.write(message)

    def write(self, message: Message):
        """
        Append message to file
        :param message: message
        """
        self.file.write(message.date + ";" + message.time + ";" + str(message.index) + ";" + str(message.value) + "\n")
        self.lastUpdate = time.time()

    def close(self):
        """
        Close file
        """
        logging.debug('closing file ' + self.topic)
        self.file.flush()
        self.file.close()