error_handling_ex

bad_ex.py

import time
import logger

class DataTransport:
    retry_threshold: int = 5
    retry_n_times: int = 5

    def __init__(self, connector):
        self._connector = connector
        self.connection = None

    def connect(self):
        for _ in range(self.retry_n_times):
            try:
                self.connection = self._connector.connect()
            except ConnectionError as e:
                logger.info(
                    e, "Try To connect", self.retry_n_times
                )
                time.sleep(self.retry_threshold)
            else:
                return self.connection

        raise ConnectionError(
            f"{self.retry_n_times} times fail to connect"
        )

    def deliver_event(self, event):
        try:
            self.connect()
            data = event.decode()
            self.send(data)

        # 문맥상 관계가 크게 없는 에러(ConnectionError, ValueError)
        # 함수의 책임을 분산하기 위해서는 두 에러를 분리해야 함
        except ConnectionError as e:
            logger.info("Fail to connect", e)
            raise

        # event 의 decode 메서드에 속한 에러
        except ValueError as e:
            logger.info("Wrong data include", event, e)
            raise

    def send(self, data):
        return self.connection.send(data)

good_ex.py

import time
import logger


def connect_with_retry(connector, retry_n_times, retry_threshold: int = 5):
    for _ in range(retry_n_times):
        try:
            return connector.connect()
        except ConnectionError as e:
            logger.info(
                e, "Try To connect", retry_n_times
            )
            time.sleep(retry_threshold)

    exc = ConnectionError(f"{retry_n_times} times fail to connect")
    logger.info(exc)
    raise exc


class DataTransport:
    retry_threshold: int = 5
    retry_n_times: int = 5

    def __init__(self, connector):
        self._connector = connector
        self.connection = None

    def deliver_event(self, event):
        self.connection = connect_with_retry(self._connector, self.retry_n_times, self.retry_threshold)
        self.send(event)

    def send(self, event):
        try:
            return self.connection.send(event.decode())
        except ValueError as e:
            logger.info()
            raise e