How to get User id for Send multicast messages

Question

Hi,

I created a channel and user get connected by the channel link. Now I want that the all connected user recive my message to all connected user from API request. To send message I need user Id's and here I was struggling to get the all connected user ID's.

Reference for [Send Multicast Messages](https://developers.line.me/en/reference/messaging-api/#send-multicast-messages) : https://developers.line.me/en/reference/messaging-api/#send-multicast-messages

Please help me to get out of it.

Zoltan · Accepted Answer

I'm struggling with something similar. 
Apparently, there's no way to get a list of connected users' IDs, which is a joke in my opinion. 

As far as I know, the best approach is to save user id to some database when the user befriends your channel.

1) User signs up for your channel
2) A request is sent to your webhook
3) Save user id to DB for future use

Q&A

How to get User id for Send multicast messages