49 lines
1.0 KiB
Elixir
49 lines
1.0 KiB
Elixir
defmodule SlaxWeb.OnlineUsers do
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alias Phoenix.Presence
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alias SlaxWeb.Presence
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@topic "online_users"
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def list do
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@topic
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|> Presence.list()
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|> Enum.into(
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%{},
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fn {id, %{metas: metas}} ->
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{String.to_integer(id), length(metas)}
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end
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)
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end
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def track(pid, user) do
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with {:ok, _} <- Presence.track(pid, @topic, user.id, %{}) do
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:ok
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end
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end
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def online?(online_users, user_id) do
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Map.get(online_users, user_id, 0) > 0
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end
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def subscribe do
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Phoenix.PubSub.subscribe(Slax.PubSub, @topic)
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end
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def update(online_users, %{joins: joins, leaves: leaves}) do
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online_users
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|> process_updates(joins, &Kernel.+/2)
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|> process_updates(leaves, &Kernel.-/2)
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end
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defp process_updates(online_users, updates, operation) do
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Enum.reduce(updates, online_users, fn {id, %{metas: metas}}, acc ->
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Map.update(
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acc,
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String.to_integer(id),
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length(metas),
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&operation.(&1, length(metas))
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)
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end)
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end
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end
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