nathanl
Example usage of `Phoenix.Presence.list/2`?
I’m trying to understand how to use Phoenix.Presence.list/2. It shows the arguments as module, topic.
My guess was that module should be the channel module, but when I call Phoenix.Presence.list(MyApp.MyChannel, "my_topic"), I get an ** (EXIT) no process error from GenServer.call.
I’m using Presence in the channel module the way the docs show, and I’m successfully getting presence_state and presence_diff messages in the browser.
My goal is to get a list of connected users for that topic so that I can send each one of them some data customized for their user id.
Am I using Phoenix.Presence.list/2 wrong?
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dom
It’s referring to your app’s presence module. Phoenix.Presence.list(MyApp.Presence, "my_topic") should do the trick. But you can also just call MyApp.Presence.list("my_topic"), that function is inserted into your presence module in this macro.
nathanl
Oh! Yes, that works. Thanks! 
I guess that implies that each topic needs a globally unique name, even though they’re handled by different channels. 
OvermindDL1
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