handle leaves and joins in the same function

This commit is contained in:
Berenice Medel Sánchez 2021-12-10 10:20:07 -06:00 committed by Chris McCord
parent c22e104a24
commit 0579f9f293

View file

@ -55,16 +55,16 @@ defmodule Phoenix.Presence.Client do
end end
defp track_pid(state, pid, topic, key, meta) do defp track_pid(state, pid, topic, key, meta) do
#presences are handled when the presence_diff event received
case Map.fetch(state.topics, topic) do case Map.fetch(state.topics, topic) do
{:ok, _topic_content} -> {:ok, _topic_content} ->
state.presence_mod.track(pid, topic, key, meta) state.presence_mod.track(pid, topic, key, meta)
update_topics_state(:add_new_presence, state, topic, key, meta) state
:error -> :error ->
# subscribe to topic we weren't yet tracking # subscribe to topic we weren't yet tracking
Phoenix.PubSub.subscribe(state.pubsub, topic) Phoenix.PubSub.subscribe(state.pubsub, topic)
state.presence_mod.track(pid, topic, key, meta) state.presence_mod.track(pid, topic, key, meta)
update_topics_state(:add_new_topic, state, topic, key, meta) state
end end
end end
@ -72,10 +72,7 @@ defmodule Phoenix.Presence.Client do
state.presence_mod.untrack(pid, topic, key) state.presence_mod.untrack(pid, topic, key)
# remove presence from state.topics # remove presence from state.topics
if Map.has_key?(state.topics, topic) do if Map.has_key?(state.topics, topic) do
presences_count = presences_count = topic_presences_count(state, topic)
state.topics[topic]
|> Map.keys()
|> Enum.count()
# if no more presences for given topic, unsubscribe # if no more presences for given topic, unsubscribe
if presences_count == 0 do if presences_count == 0 do
@ -89,61 +86,62 @@ defmodule Phoenix.Presence.Client do
end end
end end
# is a join defp merge_diff(state, topic, %{leaves: leaves, joins: joins}) do
defp merge_diff(state, topic, %{leaves: leaves, joins: joins}) when map_size(leaves) == 0 do #add new topic if needed
updated_state =
if Map.has_key?(state.topics, topic) do
state
else
update_topics_state(:add_new_topic, state, topic)
end
# merge diff into state.topics # merge diff into state.topics
joined_key = Map.keys(joins) |> hd {updated_state, _topic} = Enum.reduce(joins, {updated_state, topic}, &handle_join/2)
joined_meta = joins[joined_key].metas |> hd {updated_state, _topic} = Enum.reduce(leaves, {updated_state, topic}, &handle_leave/2)
state.client.handle_join(topic, joined_key, joined_meta, state) # if no more presences for given topic, unsubscribe and remove topic
if topic_presences_count(updated_state, topic) == 0 do
if Map.has_key?(state.topics, topic) do
update_topics_state(:add_new_presence, state, topic, joined_key, joined_meta)
else
update_topics_state(:add_new_topic, state, topic, joined_key, joined_meta)
end
end
defp merge_diff(state, topic, %{leaves: leaves, joins: joins}) when map_size(joins) == 0 do
presences_count =
state.topics[topic]
|> Map.keys()
|> Enum.count()
left_key = Map.keys(leaves) |> hd
left_meta = leaves[left_key].metas |> hd
state.client.handle_leave(topic, left_key, left_meta, state)
# if no more presences for given topic, unsubscribe
if presences_count == 0 do
Phoenix.PubSub.unsubscribe(state.pubsub, topic) Phoenix.PubSub.unsubscribe(state.pubsub, topic)
update_topics_state(:remove_topic, state, topic, left_key) update_topics_state(:remove_topic, updated_state, topic)
else else
update_topics_state(:remove_presence, state, topic, left_key) updated_state
end end
end end
defp update_topics_state(:add_new_topic, %{topics: topics} = state, topic, key, meta) do defp handle_join({joined_key, meta}, {state, topic}) do
topic_presences = %{key => meta} joined_meta = Map.get(meta, :metas, [])
updated_topics = Map.put_new(topics, topic, topic_presences) updated_state = update_topics_state(:add_new_presence, state, topic, joined_key, joined_meta)
state.client.handle_join(topic, joined_key, joined_meta, state)
{updated_state, topic}
end
defp handle_leave({left_key, meta}, {state, topic}) do
left_meta = Map.get(meta, :metas, [])
updated_state = update_topics_state(:remove_presence, state, topic, left_key)
state.client.handle_leave(topic, left_key, meta, state)
{updated_state, topic}
end
defp update_topics_state(:add_new_topic, %{topics: topics} = state, topic) do
updated_topics = Map.put_new(topics, topic, %{})
Map.put(state, :topics, updated_topics)
end
defp update_topics_state(:remove_topic, %{topics: topics} = state, topic) do
updated_topics = Map.delete(topics, topic)
Map.put(state, :topics, updated_topics) Map.put(state, :topics, updated_topics)
end end
defp update_topics_state(:add_new_presence, %{topics: topics} = state, topic, key, meta) do defp update_topics_state(:add_new_presence, %{topics: topics} = state, topic, key, meta) do
updated_topic = updated_topic =
topics[topic] topics[topic]
|> Map.put_new(key, meta) |> Map.put(key, meta)
updated_topics = Map.put(topics, topic, updated_topic) updated_topics = Map.put(topics, topic, updated_topic)
Map.put(state, :topics, updated_topics) Map.put(state, :topics, updated_topics)
end end
defp update_topics_state(:remove_topic, %{topics: topics} = state, topic, _key) do
updated_topics = Map.delete(topics, topic)
Map.put(state, :topics, updated_topics)
end
defp update_topics_state(:remove_presence, %{topics: topics} = state, topic, key) do defp update_topics_state(:remove_presence, %{topics: topics} = state, topic, key) do
updated_presences = updated_presences =
topics[topic] topics[topic]
@ -153,4 +151,10 @@ defmodule Phoenix.Presence.Client do
Map.put(state, :topics, updated_topics) Map.put(state, :topics, updated_topics)
end end
defp topic_presences_count(state, topic) do
state.topics[topic]
|> Map.keys()
|> Enum.count()
end
end end