# TheEnd

This library provides a graceful shutdown support for your Phoenix, or plain Plug application.

Original idea is

https://gist.github.com/aaronjensen/33cc2aeb74746cac3bcb40dcefdd9c09

Many of the logic in this library is borrowed from here.
I added a little bit componentization

Now, with this library, you can support graceful shutdown for your application built with

- Plug
- Phoenix 1.3
- 1.2 or more older version of Phoenix

And you also can use only AcceptanceStopper, without waiting pending requests to finish.
This is for WebSocket application.

## Installation

If [available in Hex](https://hex.pm/docs/publish), the package can be installed
by adding `the_end` to your list of dependencies in `mix.exs`:

```elixir
def deps do
  [
    {:the_end, "~> 0.1.3"}
  ]
end
```

Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
be found at [https://hexdocs.pm/the_end](https://hexdocs.pm/the_end).

## Usage

### Phoenix Endpoint

```elixir
  children = [

    supervisor(MyApp.Endpoint, []),

    # ... other supervisors/workers

    # you should set this supervisor at last
    supervisor(
      TheEnd.Supervisor.Phoenix,
      [[timeout: 10_000, endpoint: MyApp.Endpoint]],
      [shutdown: 15_000]
    )
  ]
  Supervisor.start_link(children, strategy: :one_for_one, name: MyApp.Supervisor)
```

If your Phoenix version is 1.2 or older, use TheEnd.Supervisor.LegacyPhoenix instead of TheEnd.Supervisor.Phoenix.

### Plug

Your need a Plug wrapper supervisor

```elixir
defmodule MyApp.HTTPSupervisor do

  use Supervisor

  def start_link() do
    Supervisor.start_link(__MODULE__, nil, name: __MODULE__)
  end

  def init(_args) do
      [Plug.Adapters.Cowboy.child_spec(:http,
        MyApp.Router, [], [port: 3000])]
    |> supervise(strategy: :one_for_one)
  end

end
```

```elixir
  children = [

    supervisor(MyApp.HTTPSupervisor)

    # ... other supervisors/workers

    # you should set this supervisor at last
    supervisor(
      TheEnd.Supervisor.Plug,
      [[timeout: 10_000, endpoint: MyApp.HTTPSupervisor]],
      [shutdown: 15_000]
    )
  ]

  Supervisor.start_link(children, strategy: :one_for_one, name: MyApp.Supervisor)
```

Or else if you don't need to wait for requests to finish.
(For instance, WebSocket application)

```elixir
  children = [

    supervisor(MyApp.HTTPSupervisor)

    # ... other supervisors/workers

    # you should set this worker at last
    worker(
      TheEnd.AcceptanceStopper,
      [[gatherer: TheEnd.ListenerGatherer.Plug, endpoint: MyApp.HTTPSupervisor]]
    )
  ]

  Supervisor.start_link(children, strategy: :one_for_one, name: MyApp.Supervisor)
```

You can choose **gatherer** option for your situation

- TheEnd.ListenerGatherer.Plug
- TheEnd.ListenerGatherer.Phoenix
- TheEnd.ListenerGatherer.LegacyPhoenix