Python

Python @classmethod

Python tip:

You can use @classmethod to create class methods.

For example, you can create a class method that loads events from a JSON string message👇

import datetime
import json


class UserRegistered:
    def __init__(self, username, event_time):
        self.username = username
        self.event_time = event_time

    @classmethod
    def from_event_message(cls, message):
        message = json.loads(message)

        return cls(
            username=message["username"],
            event_time=datetime.datetime.fromisoformat(message["event_time"]),
        )


message = '{"username": "johndoe", "event_time": "2021-04-26T20:00:00"}'
event = UserRegistered.from_event_message(message)
print(event.username, event.event_time)
# => johndoe 2021-04-26 20:00:00