MemoryMappedFile.py

import os
import json
import time
import pandas as pd
import mmap
import gc

data_path = "data.bin"
response_path = "responce.bin"


class MMFServer():
    def __init__(self, update_status, *args):
        self.update_status = update_status

    def process(self, stop_event, data):
        while not stop_event.is_set():
            try:
                if os.path.exists(data_path):
                    with open(data_path, "r+b") as f:
                        mmf = mmap.mmap(f.fileno(), 0)
                        msg = mmf.read()
                        mmf.close()
                        end_time = time.time()
                        self.file_size = len(msg)
                        new_data = json.loads(bytes(msg).decode("utf-8"))
                        data['file_name'] = new_data['file_name']
                        data['start_time'] = new_data['start_time']
                        data['body'] = pd.read_json(new_data['body'])
                        del new_data
                        duration = end_time - data['start_time']
                        speed = self.file_size/1024/(duration+0.001)
                        response = f"\nПередача данных прошла успешно.\nНазвание файла: {data['file_name']}\nСпособ передачи: Memory Mapped File\nОбъём данных: {self.file_size/1024} килобайт.\nВремя передачи: {duration} секунд.\nСкорость передачи: {speed} килобайт в секунду\n"
                        self.update_status(response)
                    os.remove(data_path)
                    with open(response_path, "w+b") as f:
                        f.write(b'\x00' * len(bytes(response, "utf-8")))
                        f.flush()
                        mmf = mmap.mmap(f.fileno(), 0)
                        mmf.write(bytes(response, "utf-8"))
                        mmf.close()
                    # Очистка
                    self.file_size = None
                    del msg
                    del end_time
                    del duration
                    del speed
                    del response
                    del mmf
                    gc.collect()
            except ValueError as e:
                # print(e)
                continue


class MMFClient():
    def __init__(self, update_status, *args):
        self.update_status = update_status

    def send(self, data):
        with open(data_path, "w+b") as f:
            f.write(b'\x00' * len(data))
            mmf = mmap.mmap(f.fileno(), 0)
            mmf.write(data)
            mmf.close()
        while True:
            try:
                if os.path.exists(response_path):
                    with open(response_path, "r+b") as f:
                        mmf = mmap.mmap(f.fileno(), 0)
                        msg = mmf.read()
                        mmf.close()
                        self.update_status(msg.decode('utf-8'))
                        break
            except PermissionError as e:
                print(e)
                continue
            except ValueError as e:
                # print(e)
                continue
        os.remove(response_path)

    def close(self):
        pass