Phoenix.PubSub
Serves as a Notification and PubSub layer for broad use-cases. Used internally by Channels for pubsub broadcast.
Example
iex> PubSub.subscribe(self, "user:123")
:ok
iex> Process.info(self)[:messages]
[]
iex> PubSub.subscribers("user:123")
[#PID<0.169.0>]
iex> PubSub.broadcast "user:123", {:user_update, %{id: 123, name: "Shane"}}
:ok
iex> Process.info(self)[:messages]
{:user_update, %{id: 123, name: "Shane"}}Summary
| active?(topic_name) | Check if PubSub is active. To be active it must be created and have subscribers |
| broadcast(topic_name, message) | Broadcasts a message to the topic’s subscribers |
| broadcast_from(from_pid, topic_name, message) | Broadcasts a message to the topics’s subscribers, excluding broadcaster from receiving the message it sent out |
| create(topic_name) | Creates a topic for pubsub broadcast to subscribers |
| delete(topic_name) | Removes topic from process group if inactive |
| exists?(topic_name) | Checks if a given topic is registered as a process group |
| list() | Returns a List of all Phoenix PubSubs from :pg2 |
| subscribe(pid, topic_name) | Adds subsriber pid to the given topic |
| subscribers(topic_name) | Returns the List of subsriber pids for the give topic |
| unsubscribe(pid, topic_name) | Removes the given subscriber from the topic |
Functions
Check if PubSub is active. To be active it must be created and have subscribers
Broadcasts a message to the topic’s subscribers
- topic_name - The String name of the topic
- message - The term to broadcast
Examples
iex> PubSub.broadcast("mytopic", :hello)To exclude the broadcaster from receiving the message, use broadcast_from/3
Broadcasts a message to the topics’s subscribers, excluding broadcaster from receiving the message it sent out
- topic_name - The String name of the topic
- message - The term to broadcast
Examples
iex> PubSub.broadcast_from(self, "mytopic", :hello)Creates a topic for pubsub broadcast to subscribers
- topic_name - The String name of the topic
Examples
iex> PubSub.create("mytopic")
:okRemoves topic from process group if inactive
Examples
iex> PubSub.delete("mytopic")
:ok
iex> PubSub.delete("activetopic")
{:error, :active}Adds subsriber pid to the given topic
- pid - The Pid of the subscriber
- topic_name - The String name of the topic
Examples
iex> PubSub.subscribe(self, "mytopic")Returns the List of subsriber pids for the give topic
Examples
iex> PubSub.subscribers("mytopic")
[]
iex> PubSub.subscribe(self, "mytopic")
:ok
iex> PubSub.subscribers("mytopic")
[#PID<0.41.0>]