# EventBus
[](https://travis-ci.org/mustafaturan/event_bus)
Simple event bus implementation using ETS as an event store.
## Installation
The package can be installed by adding `event_bus` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[{:event_bus, "~> 0.2.1"}]
end
```
## Usage
Register events in `config.exs` (recommended way)
In your config.exs you can register events
```elixir
config :event_bus, events: [:message_received, :another_event_occured]
```
Register events on demand
```elixir
EventBus.register_event(:my_test_event_occured)
```
Subscribe to the 'event bus'
```elixir
EventBus.subscribe(MyEventListener)
```
Unsubscribe from the 'event bus'
```elixir
EventBus.unsubscribe(MyEventListener)
```
List subscribers
```elixir
EventBus.subscribers()
```
Notify all subscribers with any type of data
```elixir
EventBus.notify(:hello_received, %{message: "Hello"})
EventBus.notify(:bye_received, [user_id: 1, goal: "exit"])
```
Fetch event data
```elixir
EventBus.fetch_event_data({:bye_received, event_key})
```
Mark as completed on Event Watcher
```elixir
EventBus.complete({MyEventListener, :bye_received, event_key})
```
Mark as skipped on Event Watcher
```elixir
EventBus.skip({MyEventListener, :bye_received, event_key})
```
### Sample Listener Implementation
```elixir
defmodule MyEventListener do
...
def process({:hello_received, event_key} = event_shadow) do
GenServer.cast(__MODULE__, event_shadow)
end
def process({:bye_received, event_key}) do
event_data = EventBus.fetch_event_data({:bye_received, event_key})
# do sth with event_data
# update the watcher!
EventBus.complete({__MODULE__, :bye_received, event_key})
:ok
end
def process({event_type, event_key}) do
EventBus.skip({__MODULE__, event_type, event_key})
:ok
end
...
def handle_cast({:hello_received, event_key}, state) do
event_data = EventBus.fetch_event_data({:hello_received, event_key})
# do sth with event_data
# update the watcher!
EventWatcher.complete({__MODULE__, :hello_received, event_key})
...
{:noreply, state}
end
...
end
```
### Module Documentation
Module docs can be found at [https://hexdocs.pm/event_bus](https://hexdocs.pm/event_bus).
## Contributing
### Issues, Bugs, Documentation, Enhancements
1. Fork the project
2. Make your improvements and write your tests(make sure you covered all the cases).
3. Make a pull request.
## License
MIT
