业精于勤，荒于嬉;行成于思，毁于随。
Clear the deviceToken when the user logs out and report the deviceToken when the user logs in.
This kind of social application seems to use heartbeat to determine whether the client is still online, and then decides whether to send push messages
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Clear the deviceToken when the user logs out and report the deviceToken when the user logs in.
This kind of social application seems to use heartbeat to determine whether the client is still online, and then decides whether to send push messages